Gardening Without Irrigation: or without much, anyway
by
Steve Solomon
Part 2 out of 2
that cold, damp weather will prevent germination or permanently
spoil the growth prospects of the earlier seedlings.
Cucumbers
_Sowing date:_ About May 5 to 15 at Elkton.
_Spacing:_ Most varieties usually run five about 3 feet from the
hill. Space the hills about 5 to 6 feet apart in all directions.
_Irrigation:_ Like melons. Regular and increasing amounts of
fertigation will increase the yield several hundred percent.
_Varieties:_ I've had very good results dry-gardening Amira II
(TSC), even without any fertigation at all. It is a Middle
Eastern[-]style variety that makes pickler-size thin-skinned cukes
that need no peeling and have terrific flavor. The burpless or
Japanese sorts don't seem to adapt well to drought. Most slicers
dry-garden excellently. Apple or Lemon are similar novelty heirlooms
that make very extensive vines with aggressive roots and should be
given a foot or two more elbow room. I'd avoid any variety touted as
being for pot or patio, compact, or short-vined, because of a likely
linkage between its vine structure and root system.
Eggplant
Grown without regular sprinkler irrigation, eggplant seems to get
larger and yield sooner and more abundantly. I suspect this delicate
and fairly drought-resistant tropical species does not like having
its soil temperature lowered by frequent watering.
_Sowing date:_ Set out transplants at the usual time, about two
weeks after the tomatoes, after all frost danger has passed and
after nights have stably warmed up above 50 degree F.
_Spacing:_ Double dig and deeply fertilize the soil under each
transplant. Separate plants by about 3 feet in rows about 4 feet
apart.
_Irrigation:_ Will grow and produce a few fruit without any
watering, but a bucket of fertigation every three to four weeks
during summer may result in the most luxurious, hugest, and
heaviest-bearing eggplants you've ever grown.
_Varieties: _I've noticed no special varietal differences in ability
to tolerate dryish soil. I've had good yields from the regionally
adapted varieties Dusky Hybrid, Short Tom, and Early One.
Endive
A biennial member of the chicory family, endive quickly puts down a
deep taproot and is naturally able to grow through prolonged
drought. Because endive remains bitter until cold weather, it
doesn't matter if it grows slowly through summer, just so long as
rapid leaf production resumes in autumn.
_Sowing date:_ On irrigated raised beds endive is sown around August
1 and heads by mid-October. The problem with dry-gardened endive is
that if it is spring sown during days of increasing daylength when
germination of shallow-sown small seed is a snap, it will bolt
prematurely. The crucial moment seems to be about June 1. April/May
sowings bolt in July/August,: after June 1, bolting won't happen
until the next spring, but germination won't happen without
watering. One solution is soaking the seeds overnight, rinsing them
frequently until they begin to sprout, and fluid drilling them.
_Spacing:_ The heads become huge when started in June. Sow in rows 4
feet apart and thin gradually until the rosettes are 3 inches in
diameter, then thin to 18 inches apart.
_Irrigation:_ Without a drop of moisture the plants, even as tiny
seedlings, will grow steadily but slowly all summer, as long as no
other crop is invading their root zone. The only time I had trouble
was when the endive row was too close to an aggressive row of yellow
crookneck squash. About August, the squash roots began invading the
endive's territory and the endive got wilty.
A light side-dressing of complete organic fertilizer or compost in
late September will grow the hugest plants imaginable.
_Varieties:_ Curly types seem more tolerant to rain and frost during
winter than broad-leaf Batavian varieties. I prefer President (TSC).
Herbs
Most perennial and biennial herbs are actually weeds and wild
hillside shrubs from Mediterranean climates similar to that of
Southern California. They are adapted to growing on winter rainfall
and surviving seven to nine months without rainfall every summer. In
our climate, merely giving them a little more elbow room than
usually offered, thorough weeding, and side-dressing the herb garden
with a little compost in fall is enough coddling. Annuals such as
dill and cilantro are also very drought tolerant. Basil, however,
needs considerable moisture.
Kale
Depending on the garden for a significant portion of my annual
caloric intake has gradually refined my eating habits. Years ago I
learned to like cabbage salads as much as lettuce. Since lettuce
freezes out many winters (19-21 degree F), this adjustment has proved
very useful. Gradually I began to appreciate kale, too, and now
value it as a salad green far more than cabbage. This personal
adaptation has proved very pro-survival, because even savoy cabbages
do not grow as readily or yield nearly as much as kale. And kale is
a tad more cold hardy than even savoy cabbage.
You may be surprised to learn that kale produces more complete
protein per area occupied per time involved than any legume,
including alfalfa. If it is steamed with potatoes and then mashed,
the two vegetables complement and flavor each other. Our region
could probably subsist quite a bit more healthfully than at present
on potatoes and kale. The key to enjoying kale as a salad component
is varietal choice, preparation, and using the right parts of the
plant. Read on.
_Sowing date:_ With irrigation, fast-growing kale is usually started
in midsummer for use in fall and winter. But kale is absolutely
biennial--started in March or April, it will not bolt until the next
spring. The water-wise gardener can conveniently sow kale while
cool, moist soil simplifies germination. Starting this early also
produces a deep root system before the soil dries much, and a much
taller, very useful central stalk on oleracea types, while early
sown Siberian (Napa) varieties tend to form multiple rosettes by
autumn, also useful at harvest time.
_Spacing: _Grow like broccoli, spaced 4 feet apart.
_Irrigation:_ Without any water, the somewhat stunted plants will
survive the summer to begin rapid growth as soon as fall rains
resume. With the help of occasional fertigation they grow lushly and
are enormous by September. Either way, there still will be plenty of
kale during fall and winter.
_Harvest:_ Bundles of strong-flavored, tough, large leaves are sold
in supermarkets but are the worst-eating part of the plant. If
chopped finely enough, big raw leaves can be masticated and
tolerated by people with good teeth. However, the tiny leaves are
far tenderer and much milder. The more rosettes developed on
Siberian kales, the more little leaves there are to be picked. By
pinching off the central growing tip in October and then gradually
stripping off the large shading leaves, _oleracea_ varieties may be
encouraged to put out dozens of clusters of small, succulent leaves
at each leaf notch along the central stalk. The taller the stalk
grown during summer, the more of these little leaves there will be.
Only home gardeners can afford the time to hand pick small leaves.
_Varieties:_ I somewhat prefer the flavor of Red Russian to the
ubiquitous green Siberian, but Red Russian is very slightly less
cold hardy. Westland Winter (TSC) and Konserva (JSS) are tall
European oleracea varieties. Winterbor F1 (JSS, TSC) is also
excellent. The dwarf "Scotch" kales, blue or green, sold by many
American seed companies are less vigorous types that don't produce
nearly as many gourmet little leaves. Dwarfs in any species tend to
have dwarfed root systems.
Kohlrabi (Giant)
Spring-sown market kohlrabi are usually harvested before hot weather
makes them get woody. Irrigation is not required if they're given a
little extra elbow room. With ordinary varieties, try thinning to 5
inches apart in rows 2 to 3 feet apart and harvest by thinning
alternate plants. Given this additional growing room, they may not
get woody until midsummer. On my irrigated, intensive bed I always
sow some more on August 1, to have tender bulbs in autumn.
Kohlrabi was once grown as European fodder crop; slow-growing
farmers, varieties grow huge like rutabagas. These field types have
been crossed with table types to make "giant" table varieties that
really suit dry gardening. What to do with a giant kohlrabi (or any
bulb getting overblown)? Peel, grate finely, add chopped onion,
dress with olive oil and black pepper, toss, and enjoy this old
Eastern European mainstay.
_Sowing date:_ Sow giant varieties during April, as late as possible
while still getting a foot-tall plant before really hot weather.
_Spacing:_ Thin to 3 feet apart in rows 4 feet apart.
_Irrigation:_ Not absolutely necessary on deep soil, but if they get
one or two thorough fertigations during summer their size may
double.
_Varieties:_ A few American seed companies, including Peace Seeds,
have a giant kohlrabi of some sort or other. The ones I've tested
tend to be woody, are crude, and throw many off-types, a high
percentage of weak plants, and/or poorly shaped roots. By the time
this book is in print, Territorial should list a unique Swiss
variety called Superschmeltz, which is uniformly huge and stays
tender into the next year.
Leeks
Unwatered spring-sown bulbing onions are impossible. Leek is the
only allium I know of that may grow steadily but slowly through
severe drought; the water-short gardener can depend on leeks for a
fall/winter onion supply.
_Sowing date:_ Start a row or several short rows about 12 inches
apart on a nursery bed in March or early April at the latest. Grow
thickly, irrigate during May/June, and fertilize well so the
competing seedlings get leggy.
_Spacing:_ By mid-to late June the seedlings should be slightly
spindly, pencil-thick, and scallion size. With a sharp shovel, dig
out the nursery row, carefully retaining 5 or 6 inches of soil below
the seedlings. With a strong jet of water, blast away the soil and,
while doing this, gently separate the tangled roots so that as
little damage is done as possible. Make sure the roots don't dry out
before transplanting. After separation, I temporarily wrap bundled
seedlings in wet newspaper.
Dig out a foot-deep trench the width of an ordinary shovel and
carefully place this earth next to the trench. Sprinkle in a heavy
dose of organic fertilizer or strong compost, and spade that in so
the soil is fluffy and fertile 2 feet down. Do not immediately
refill the trench with the soil that was dug out. With a shovel
handle, poke a row of 6-inch-deep holes along the bottom of the
trench. If the nursery bed has grown well there should be about 4
inches of stem on each seedling before the first leaf attaches. If
the weather is hot and sunny, snip off about one-third to one-half
the leaf area to reduce transplanting shock. Drop one leek seedling
into each hole up to the point that the first leaf attaches to the
stalk, and mud it in with a cup or two of liquid fertilizer. As the
leeks grow, gradually refill the trench and even hill up soil around
the growing plants. This makes the better-tasting white part of the
stem get as long as possible. Avoid getting soil into the center of
the leek where new leaves emerge, or you'll not get them clean after
harvest.
Spacing of the seedlings depends on the amount of irrigation. If
absolutely none at all, set them 12 inches apart in the center of a
row 4 feet wide. If unlimited water is available, give them 2 inches
of separation. Or adjust spacing to the water available. The plants
grow slowly through summer, but in autumn growth will accelerate,
especially if they are side-dressed at this time.
_Varieties:_ For dry gardening use the hardier, more vigorous winter
leeks. Durabel (TSC) has an especially mild, sweet flavor. Other
useful varieties include Giant Carentian (ABL), Alaska (STK), and
Winter Giant (PEA).
Lettuce
Spring-sown lettuce will go to large sizes, remaining sweet and
tender without irrigation if spaced 1 foot apart in a single row
with 2 feet of elbow room on each side. Lettuce cut after mid-June
usually gets bitter without regular, heavy irrigation. I reserve my
well-watered raised bed for this summer salad crop. Those very short
of water can start fall/winter lettuce in a shaded, irrigated
nursery bed mid-August through mid-September and transplant it out
after the fall rains return. Here is one situation in which
accelerating growth with cloches or cold frames would be very
helpful.
Water-Wise Cucurbits
The root systems of this family are far more extensive than most
people realize. Usually a taproot goes down several feet and then,
soil conditions permitting, thickly occupies a large area,
ultimately reaching down 5 to 8 feet. Shallow feeder roots also
extend laterally as far as or farther than the vines reach at their
greatest extent.
Dry gardeners can do several things to assist cucurbits. First, make
sure there is absolutely no competition in their root zone. This
means[i]one plant per hill, with the hills separated in all
directions a little farther than the greatest possible extent of the
variety's ultimate growth.[i] Common garden lore states that
squashes droop their leaves in midsummer heat and that this trait
cannot be avoided and does no harm. But if they've grown as
described above, on deep, open soil, capillarity and surface
moisture reserves ensure there usually will be no midday wilting,
even if there is no watering. Two plants per hill do compete and
make each other wilt.
Second, double dig and fertilize the entire lateral root zone.
Third, as much as possible, avoid walking where the vines will
ultimately reach to avoid compaction. Finally, [i]do not transplant
them.[i] This breaks the taproot and makes the plant more dependent
on lateral roots seeking moisture in the top 18 inches of soil.
Melons
_Sowing date:_ As soon as they'll germinate outdoors: at Elkton, May
15 to June 1. Thin to a single plant per hill when there are about
three true leaves and the vines are beginning to run.
_Spacing:_ Most varieties will grow a vine reaching about 8 feet in
diameter. Space the hills 8 feet apart in all directions.
_Irrigation:_ Fertigation every two to three weeks will increase the
yield by two or three times and may make the melons sweeter. Release
the water/fertilizer mix close to the center of the vine, where the
taproot can use it.
_Varieties:_ Adaptation to our cool climate is critical with melons;
use varieties sold by our regional seed companies. Yellow Doll
watermelons (TSC) are very early and seem the most productive under
the most droughty conditions. I've had reasonable results from most
otherwise regionally adapted cantaloupes and muskmelons. Last year a
new hybrid variety, Passport (TSC), proved several weeks earlier
than I'd ever experienced and was extraordinarily prolific and
tasty.
Onions/Scallions
The usual spring-sown, summer-grown bulb onions and scallions only
work with abundant irrigation. But the water-short, water-wise
gardener can still supply the kitchen with onions or onion
substitutes year-round. Leeks take care of November through early
April. Overwintered bulb onions handle the rest of the year.
Scallions may also be harvested during winter.
_Sowing date:_ Started too soon, overwintered or short-day bulbing
onions (and sweet scallions) will bolt and form seed instead of
bulbing. Started too late they'll be too small and possibly not
hardy enough to survive winter. About August 15 at Elkton I sow
thickly in a well-watered and very fertile nursery bed. If you have
more than one nursery row, separate them about by 12 inches. Those
who miss this window of opportunity can start transplants in early
October and cover with a cloche immediately after germination, to
accelerate seedling growth during fall and early winter.
Start scallions in a nursery just like overwintered onions, but
earlier so they're large enough for the table during winter, I sow
them about mid-July.
_Spacing:_ When seedlings are about pencil thick (December/January
for overwintering bulb onions), transplant them about 4 or 5 inches
apart in a single row with a couple of feet of elbow room on either
side. I've found I get the best growth and largest bulbs if they
follow potatoes. After the potatoes are dug in early October I
immediately fertilize the area heavily and till, preparing the onion
bed. Klamath Basin farmers usually grow a similar rotation: hay,
potatoes, onions.
Transplant scallions in October with the fall rains, about 1 inch
apart in rows at least 2 feet apart.
_Irrigation:_ Not necessary. However, side-dressing the transplants
will result in much larger bulbs or scallions. Scallions will bolt
in April; the bulbers go tops-down and begin drying down as the soil
naturally dries out.
_Varieties:_ I prefer the sweet and tender Lisbon (TSC) for
scallions. For overwintered bulb onions, grow very mild but poorly
keeping Walla Walla Sweet (JSS), Buffalo (TSC), a better keeper, or
whatever Territorial is selling at present.
Parsley
_Sowing date:_ March. Parsley seed takes two to three weeks to
germinate.
_Spacing:_ Thin to 12 inches apart in a single row 4 feet wide. Five
plants should overwhelm the average kitchen.
_Irrigation:_ Not necessary unless yield falls off during summer and
that is very unlikely. Parsley's very deep, foraging root system
resembles that of its relative, the carrot.
_Varieties:_ If you use parsley for greens, variety is not critical,
though the gourmet may note slight differences in flavor or amount
of leaf curl. Another type of parsley is grown for edible roots that
taste much like parsnip. These should have their soil prepared as
carefully as though growing carrots.
Peas
This early crop matures without irrigation. Both pole and bush
varieties are planted thickly in single rows about 4 feet apart. I
always overlook some pods, which go on to form mature seed. Without
overhead irrigation, this seed will sprout strongly next year.
Alaska (soup) peas grow the same way.
Peppers
Pepper plants on raised beds spaced the usually recommended 16 to 24
inches apart undergo intense root competition even before their
leaves form a canopy. With or without unlimited irrigation, the
plants will get much larger and bear more heavily with elbow room.
_Sowing date:_ Set out transplants at the usual time. Double dig a
few square feet of soil beneath each seedling, and make sure
fertilizer gets incorporated all the way down to 2 feet deep.
_Spacing:_ Three feet apart in rows 3 to 4 feet apart.
_Irrigation:_ Without any irrigation only the most vigorous,
small-fruited varieties will set anything. For an abundant harvest,
fertigate every three or four weeks. For the biggest pepper plants
you ever grew, fertigate every two weeks.
_Varieties:_ The small-fruited types, both hot and sweet, have much
more aggressive root systems and generally adapt better to our
region's cool weather. I've had best results with Cayenne Long Slim,
Gypsie, Surefire, Hot Portugal, the "cherries" both sweet and hot,
Italian Sweet, and Petite Sirah.
Potatoes
Humans domesticated potatoes in the cool, arid high plateaus of the
Andes where annual rainfall averages 8 to 12 inches. The species
finds our dry summer quite comfortable. Potatoes produce more
calories per unit of land than any other temperate crop. Irrigated
potatoes yield more calories and two to three times as much watery
bulk and indigestible fiber as those grown without irrigation, but
the same variety dry gardened can contain about 30 percent more
protein, far more mineral nutrients, and taste better.
_Sowing date:_ I make two sowings. The first is a good-luck ritual
done religiously on March 17th--St. Patrick's Day. Rain or shine, in
untilled mud or finely worked and deeply fluffed earth, I still
plant 10 or 12 seed potatoes of an early variety. This provides for
summer.
The main sowing waits until frost is unlikely and I can dig the
potato rows at least 12 inches deep with a spading fork, working in
fertilizer as deeply as possible and ending up with a finely
pulverized 24-inch-wide bed. At Elkton, this is usually mid-to late
April. There is no rush to plant. Potato vines are not frost hardy.
If frosted they'll regrow, but being burned back to the ground
lowers the final yield.
_Spacing:_ I presprout my seeds by spreading them out in daylight at
room temperature for a few weeks, and then plant one whole,
sprouting, medium-size potato every 18 inches down the center of the
row. Barely cover the seed potato. At maturity there should be
2[f]1/2 to 3 feet of soil unoccupied with the roots of any other
crop on each side of the row. As the vines emerge, gradually scrape
soil up over them with a hoe. Let the vines grow about 4 inches,
then pull up about 2 inches of cover. Let another 4 inches grow,
then hill up another 2 inches. Continue doing this until the vines
begin blooming. At that point there should be a mound of loose,
fluffy soil about 12 to 16 inches high gradually filling with tubers
lushly covered with blooming vines.
_Irrigation:_ Not necessary. In fact, if large water droplets
compact the loose soil you scraped up, that may interfere with
maximum tuber enlargement. However, after the vines are a foot long
or so, foliar feeding every week or 10 days will increase the yield.
_Varieties:_ The water-wise gardener's main potato problem is
too-early maturity, and then premature sprouting in storage. Early
varieties like Yukon Gold--even popular midseason ones like Yellow
Finn--don't keep well unless they're planted late enough to brown
off in late September. That's no problem if they're irrigated. But
planted in late April, earlier varieties will shrivel by August.
Potatoes only keep well when very cool, dark, and moist--conditions
almost impossible to create on the homestead during summer. The best
August compromise is to leave mature potatoes undug, but soil
temperatures are in the 70s during August, and by early October,
when potatoes should be lifted and put into storage, they'll already
be sprouting. Sprouting in October is acceptable for the remainders
of my St. Pat's Day sowing that I am keeping over for seed next
spring. It is not ok for my main winter storage crop. Our climate
requires very late, slow-maturing varieties that can be sown early
but that don't brown off until September. Late types usually yield
more, too.
Most of the seed potato varieties found in garden centers are early
or midseason types chosen by farmers for yield without regard to
flavor or nutrition. One, Nooksack Cascadian, is a very late variety
grown commercially around Bellingham, Washington. Nooksack is pretty
good if you like white, all-purpose potatoes.
There are much better homegarden varieties available in Ronniger's
catalog, all arranged according to maturity. For the ultimate in
earlies I suggest Red Gold. For main harvests I'd try Indian Pit,
Carole, German Butterball, Siberian, or a few experimental row-feet
of any other late variety taking your fancy.
Rutabagas
Rutabagas have wonderfully aggressive root systems and are capable
of growing continuously through long, severe drought. But where I
live, the results aren't satisfactory. Here's what happens. If I
start rutabagas in early April and space them about 2 to 3 feet
apart in rows 4 feet apart, by October they're the size of
basketballs and look pretty good; unfortunately, I harvest a hollow
shell full of cabbage root maggots. Root maggots are at their peak
in early June. That's why I got interested in dry-gardening giant
kohlrabi.
In 1991 we had about 2 surprising inches of rain late in June, so as
a test I sowed rutabagas on July 1. They germinated without more
irrigation, but going into the hot summer as small plants with
limited root systems and no irrigation at all they became somewhat
stunted. By October 1 the tops were still small and a little gnarly;
big roots had not yet formed. Then the rains came and the rutabagas
began growing rapidly. By November there was a pretty nice crop of
medium-size good-eating roots.
I suspect that farther north, where evaporation is not so severe and
midsummer rains are slightly more common, if a little irrigation
were used to start rutabagas about July 1, a decent unwatered crop
might be had most years. And I am certain that if sown at the normal
time (July 15) and grown with minimal irrigation but well spaced
out, they'll produce acceptably.
_Varieties:_ Stokes Altasweet (STK, TSC) has the best flavor.
Sorrel
This weed-like, drought-tolerant salad green is little known and
underappreciated. In summer the leaves get tough and strong
flavored; if other greens are available, sorrel will probably be
unpicked. That's ok. During fall, winter, and spring, sorrel's
lemony taste and delicate, tender texture balance tougher savoy
cabbage and kale and turn those crude vegetables into very
acceptable salads. Serious salad-eating families might want the
production of 5 to 10 row-feet.
_Sowing date:_ The first year you grow sorrel, sow mid-March to
mid-April. The tiny seed must be placed shallowly, and it sprouts
much more readily when the soil stays moist. Plant a single furrow
centered in a row 4 feet wide.
_Spacing: _As the seedlings grow, thin gradually. When the leaves
are about the size of ordinary spinach, individual plants should be
about 6 inches apart.
_Irrigation:_ Not necessary in summer--you won't eat it anyway. If
production lags in fall, winter, or spring, side-dress the sorrel
patch with a little compost or organic fertilizer.
_Maintenance:_ Sorrel is perennial. If an unusually harsh winter
freeze kills off the leaves it will probably come back from root
crowns in early spring. You'll welcome it after losing the rest of
your winter crops. In spring of the second and succeeding years
sorrel will make seed. Seed making saps the plant's energy, and the
seeds may naturalize into an unwanted weed around the garden. So,
before any seed forms, cut all the leaves and seed stalks close to
the ground; use the trimmings as a convenient mulch along the row.
If you move the garden or want to relocate the patch, do not start
sorrel again from seed. In any season dig up a few plants, divide
the root masses, trim off most of the leaves to reduce transplanting
shock, and transplant 1 foot apart. Occasional unique plants may be
more reluctant to make seed stalks than most others. Since seed
stalks produce few edible leaves and the leaves on them are very
harsh flavored, making seed is an undesirable trait. So I propagate
only seed-shy plants by root cuttings.
Spinach
Spring spinach is remarkably more drought tolerant than it would
appear from its delicate structure and the succulence of its leaves.
A bolt-resistant, long-day variety bred for summer harvest sown in
late April may still yield pickable leaves in late June or even
early July without any watering at all, if thinned to 12 inches
apart in rows 3 feet apart.
Squash, Winter and Summer
_Sowing date:_ Having warm-enough soil is everything. At Elkton I
first attempt squash about April 15. In the Willamette, May 1 is
usual. Farther north, squash may not come up until June 1. Dry
gardeners should not transplant squash; the taproot must not be
broken.
_Spacing:_ The amount of room to give each plant depends on the
potential of a specific variety's maximum root development. Most
vining winter squash can completely occupy a 10-foot-diameter
circle. Sprawly heirloom summer squash varieties can desiccate an
8-or 9-foot-diameter circle. Thin each hill to one plant, not two or
more as is recommended in the average garden book. There must be no
competition for water.
_Irrigation:_ With winter storage types, an unirrigated vine may
yield 15 pounds of squash after occupying a 10-foot-diameter circle
for an entire growing season. However, starting about July 1, if you
support that vine by supplying liquid fertilizer every two to three
weeks you may harvest 60 pounds of squash from the same area. The
first fertigation may only need 2 gallons. Then mid-July give 4;
about August 1, 8; August 15, feed 15 gallons. After that date,
solar intensity and temperatures decline, growth rate slows, and
water use also decreases. On September 1 I'd add about 8 gallons and
about 5 more on September 15 if it hadn't yet rained significantly.
Total water: 42 gallons. Total increase in yield: 45 pounds. I'd say
that's a good return on water invested.
_Varieties:_ For winter squash, all the vining winter varieties in
the C. maxima or C. pepo family seem acceptably adapted to dry
gardening. These include Buttercup, Hubbard, Delicious, Sweet Meat,
Delicata, Spaghetti, and Acorn. I wouldn't trust any of the newer
compact bush winter varieties so popular on raised beds. Despite
their reputation for drought tolerance C. mixta varieties (or cushaw
squash) were believed to be strictly hot desert or humid-tropical
varieties, unable to mature in our cool climate. However, Pepita
(PEA) is a mixta that is early enough and seems entirely unbothered
by a complete lack of irrigation. The enormous vine sets numerous
good keepers with mild-tasting, light yellow flesh.
Obviously, the compact bush summer squash varieties so popular these
days are not good candidates for withstanding long periods without
irrigation. The old heirlooms like Black Zucchini (ABL) (not Black
Beauty!) and warty Yellow Crookneck grow enormous, high-yielding
plants whose extent nearly rivals that of the largest winter squash.
They also grow a dense leaf cover, making the fruit a little harder
to find. These are the only American heirlooms still readily
available. Black Zucchini has become very raggedy; anyone growing it
should be prepared to plant several vines and accept that at least
one-third of them will throw rather off-type fruit. It needs the
work of a skilled plant breeder. Yellow Crookneck is still a fairly
"clean" variety offering good uniformity. Both have more flavor and
are less watery than the modern summer squash varieties. Yellow
Crookneck is especially rich, probably due to its thick, oily skin;
most gardeners who once grow the old Crookneck never again grow any
other kind. Another useful drought-tolerant variety is Gem,
sometimes called Rolet (TSC). It grows an extensive
winter-squash-like vine yielding grapefruit-size, excellent eating
summer squash.
Both Yellow Crookneck and Black Zucchini begin yielding several
weeks later than the modern hybrids. However, as the summer goes on
they will produce quite a bit more squash than new hybrid types. I
now grow five or six fully irrigated early hybrid plants like Seneca
Zucchini too. As soon as my picking bucket is being filled with
later-to-yield Crooknecks, I pull out the Senecas and use the now
empty irrigated space for fall crops.
Tomato
There's no point in elaborate methods--trellising, pruning, or
training--with dry-gardened tomato vines. Their root systems must be
allowed to control all the space they can without competition, so
allow the vines to sprawl as well. And pruning the leaf area of
indeterminates is counterproductive: to grow hugely, the roots need
food from a full complement of leaves.
_Sowing date:_ Set out transplants at the usual time. They might
also be jump started under cloches two to three weeks before the
last frost, to make better use of natural soil moisture.
_Spacing:_ Depends greatly on variety. The root system can occupy as
much space as the vines will cover and then some.
_Irrigation:_ Especially on determinate varieties, periodic
fertigation will greatly increase yield and size of fruit. The old
indeterminate sprawlers will produce through an entire summer
without any supplemental moisture, but yield even more in response
to irrigation.
_Variety:_ With or without irrigation or anywhere in between, when
growing tomatoes west of the Cascades, nothing is more important
than choosing the right variety. Not only does it have to be early
and able to set and ripen fruit when nights are cool, but to grow
through months without watering the plant must be highly
indeterminate. This makes a built-in conflict: most of the sprawly,
huge, old heirloom varieties are rather late to mature. But cherry
tomatoes are always far earlier than big slicers.
If I had to choose only one variety it would be the old heirloom
[Large] Red Cherry. A single plant is capable of covering a 9-to
10-foot-diameter circle if fertigated from mid-July through August.
The enormous yield of a single fertigated vine is overwhelming.
Red Cherry is a little acid and tart. Non-acid, indeterminate cherry
types like Sweetie, Sweet 100, and Sweet Millions are also workable
but not as aggressive as Red Cherry. I wouldn't depend on most bush
cherry tomato varieties. But our earliest cherry variety of all,
OSU's Gold Nugget, must grow a lot more root than top, for, with or
without supplemental water, Gold Nugget sets heavily and ripens
enormously until mid-August, when it peters out from overbearing
(not from moisture stress). Gold Nugget quits just about when the
later cherry or slicing tomatoes start ripening heavily.
Other well-adapted early determinates such as Oregon Spring and
Santiam may disappoint you. Unless fertigated. they'll set and ripen
some fruit but may become stunted in midsummer. However, a single
indeterminate Fantastic Hybrid will cover a 6-to 7-foot-diameter
circle, and grow and ripen tomatoes until frost with only a minimum
of water. I think Stupice (ABL, TSC) and Early Cascade are also
quite workable (and earlier than Fantastic in Washington).
Chapter 6
My Own Garden Plan
This chapter illustrates and explains my own dry garden. Any garden
plan is a product of compromises and preferences; mine is not
intended to become yours. But, all modesty aside, this plan results
from 20 continuous years of serious vegetable gardening and some
small degree of regional wisdom.
My wife and I are what I dub "vegetablitarians." Not vegetarians, or
lacto-ovo vegetarians because we're not ideologues and eat meat on
rare, usually festive occasions in other peoples' houses. But over
80 percent of our calories are from vegetable, fruit, or cereal
sources and the remaining percentage is from fats or dairy foods.
The purpose of my garden is to provide at least half the actual
calories we eat year-round; most of the rest comes from home-baked
bread made with freshly ground whole grains. I put at least one very
large bowl of salad on the table every day, winter and summer. I
keep us in potatoes nine months a year and produce a year's supply
of onions or leeks. To break the dietary monotony of November to
April, I grow as wide an assortment of winter vegetables as possible
and put most produce departments to shame from June through
September, when the summer vegies are "on."
The garden plan may seem unusually large, but in accordance with
Solomon's First Law of Abundance, there's a great deal of
intentional waste. My garden produces two to three times the amount
of food needed during the year so moochers, poachers, guests, adult
daughters accompanied by partners, husbands, and children, mistakes,
poor yields, and failures of individual vegetables are
inconsequential. Besides, gardening is fun.
My garden is laid out in 125-foot-long rows and one equally long
raised bed. Each row grows only one or two types of vegetables. The
central focus of my water-wise garden is its irrigation system. Two
lines of low-angle sprinklers, only 4 feet apart, straddle an
intensively irrigated raised bed running down the center of the
garden. The sprinklers I use are Naans, a unique Israeli design that
emits very little water and throws at a very low angle (available
from TSC and some garden centers). Their maximum reach is about 18
feet; each sprinkler is about 12 feet from its neighbor. On the
garden plan, the sprinklers are indicated by a circle surrounding an
"X." Readers unfamiliar with sprinkler system design are advised to
study the irrigation chapter in Growing Vegetables West of the
Cascades.
On the far left side of the garden plan is a graphic representation
of the uneven application of water put down by this sprinkler
system. The 4-foot-wide raised bed gets lots of water, uniformly
distributed. Farther away, the amount applied decreases rapidly.
About half as much irrigation lands only 6 feet from the edge of the
raised bed as on the bed itself. Beyond that the amount tapers off
to insignificance. During summer's heat the farthest 6 feet is
barely moistened on top, but no water effectively penetrates the dry
surface. Crops are positioned according to their need for or ability
to benefit from supplementation. For convenient description I've
numbered those rows.
The Raised Bed
Crops demanding the most water are grown on the raised bed. These
include a succession of lettuce plantings designed to fill the
summer salad bowl, summer spinach, spring kohlrabi, my celery patch,
scallions, Chinese cabbages, radishes, and various nursery beds that
start overwintered crops for transplanting later. Perhaps the bed
seems too large just for salad greens. But one entire meal every day
consists largely of fresh, raw, high-protein green leaves; during
summer, looseleaf or semiheading lettuce is our salad item of
choice. And our individual salad bowls are larger than most families
of six might consider adequate to serve all of them together.
If water were severely rationed I could irrigate the raised bed with
hose and nozzle and dry garden the rest, but as it is, rows 1, 2, 7,
and 8 do get significant but lesser amounts from the sprinklers.
Most of the rows hold a single plant family needing similar
fertilization and handling or, for convenience, that are sown at the
same time.
Row 1
The row's center is about 3 feet from the edge of the raised bed. In
March I sow my very first salad greens down half this row--mostly
assorted leaf lettuce plus some spinach--and six closely spaced
early Seneca Hybrid zucchini plants. The greens are all cut by
mid-June; by mid-July my better-quality Yellow Crookneck squash come
on, so I pull the zucchini. Then I till that entire row,
refertilize, and sow half to rutabagas. The nursery bed of leek
seedlings has gotten large enough to transplant at this time, too.
These go into a trench dug into the other half of the row. The leeks
and rutabagas could be reasonably productive located farther from
the sprinklers, but no vegetables benefit more from abundant water
or are more important to a self-sufficient kitchen. Rutabagas break
the winter monotony of potatoes; leeks vitally improve winter
salads, and leeky soups are a household staple from November through
March.
Row 2: Semi-Drought Tolerant Brassicas
Row 2 gets about half the irrigation of row 1 and about one-third as
much as the raised bed, and so is wider, to give the roots more
room. One-third of the row grows savoy cabbage, the rest, Brussels
sprouts. These brassicas are spaced 4 feet apart and by summer's end
the lusty sprouts form a solid hedge 4 feet tall.
Row 3: Kale
Row 3 grows 125 feet of various kales sown in April. There's just
enough overspray to keep the plants from getting gnarly. I prefer
kale to not get very stunted, if only for aesthetics: on my soil,
one vanity fertigation about mid-July keeps this row looking
impressive all summer. Other gardens with poorer soil might need
more support. This much kale may seem an enormous oversupply, but
between salads and steaming greens with potatoes we manage to eat
almost all the tender small leaves it grows during winter.
Row 4: Root Crops
Mostly carrots, a few beets. No irrigation, no fertigation, none
needed. One hundred carrots weighing in at around 5 pounds each and
20-some beets of equal magnitude make our year's supply for salads,
soups, and a little juicing.
Row 5: Dry-Gardened Salads
This row holds a few crowns of French sorrel, a few feet of parsley.
Over a dozen giant kohlrabi are spring sown, but over half the row
grows endive. I give this row absolutely no water. Again, when
contemplating the amount of space it takes, keep in mind that this
endive and kohlrabi must help fill our salad bowls from October
through March.
Row 6: Peas, Overwintered Cauliflower, and All Solanaceae
Half the row grows early bush peas. Without overhead irrigation to
bother them, unpicked pods form seed that sprouts excellently the
next year. This half of the row is rotary tilled and fertilized
again after the pea vines come out. Then it stays bare through July
while capillarity somewhat recharges the soil. About August 1, I wet
the row's surface down with hose and fan nozzle and sow overwintered
cauliflower seed. To keep the cauliflower from stunting I must
lightly hand sprinkle the row's center twice weekly through late
September. Were water more restricted I could start my cauliflower
seedlings in a nursery bed and transplant them here in October.
The other half is home to the Solanaceae: tomato, pepper, and
eggplant. I give this row a little extra width because pea vines
run, and I fertigate my Solanaceae, preferring sprawly tomato
varieties that may cover an 8-foot-diameter circle. There's also a
couple of extra bare feet along the outside because the neighboring
grasses will deplete soil moisture along the edge of the garden.
Row 7: Water-Demanding Brassicas
Moving away from irrigation on the other side of the raised bed, I
grow a succession of hybrid broccoli varieties and late fall
cauliflower. The broccoli is sown several times, 20 row-feet each
sowing, done about April 15, June 1, and July 15. The late
cauliflower goes in about July 1. If necessary I could use much of
this row for quick crops that would be harvested before I wanted to
sow broccoli or cauliflower, but I don't need more room. The first
sowings of broccoli are pulled out early enough to permit succession
sowings of arugula or other late salad greens.
Row 8: The Trellis
Here I erect a 125-foot-long, 6-foot-tall net trellis for gourmet
delicacies like pole peas and pole beans. The bean vines block
almost all water that would to on beyond it and so this row gets
more irrigation than it otherwise might. The peas are harvested
early enough to permit a succession sowing of Purple Sprouting
broccoli in mid-July. Purple Sprouting needs a bit of sprinkling to
germinate in the heat of midsummer, but, being as vigorous as kale,
once up, it grows adequately on the overspray from the raised bed.
The beans would be overwhelmingly abundant if all were sown at one
time, so I plant them in two stages about three weeks apart. Still,
a great many beans go unpicked. These are allowed to form seed, are
harvested before they quite dry, and crisp under cover away from the
sprinklers. We get enough seed from this row for planting next year,
plus all the dry beans we care to eat during winter. Dry beans are
hard to digest and as we age we eat fewer and fewer of them. In
previous years I've grown entire rows of dry legume seeds at the
garden's edge.
Row 9: Cucurbits
This row is so wide because here are grown all the spreading
cucurbits. The pole beans in row 8 tend to prevent overspray; this
dryness is especially beneficial to humidity-sensitive melons,
serendipitously reducing their susceptability to powdery mildew
diseases. All cucurbits are fertigated every three weeks. The squash
will have fallen apart by the end of September, melons are pulled
out by mid-September. The area is then tilled and fertilized, making
space to transplant overwintered spring cabbages, other overwintered
brassicas, and winter scallions in October. These transplants are
dug from nurseries on the irrigated raised bed. I could also set
cold frames here and force tender salad greens all winter.
Row 10: Unirrigated Potatoes
This single long row satisfies a potato-loving household all winter.
The quality of these dry-gardened tubers is so high that my wife
complains if she must buy a few new potatoes from the supermarket
after our supplies have become so sprouty and/or shriveled that
they're not tasty any longer.
Chapter 7
The Backyard
Water-Wise Gardener
I am an unusually fortunate gardener. After seven years of
struggling on one of the poorest growing sites in this region we now
live on 16 acres of mostly excellent, deep soil, on the floor of a
beautiful, coastal Oregon valley. My house and gardens are perched
safely above the 100-year flood line, there's a big, reliable well,
and if I ever want more than 20 gallons per minute in midsummer,
there's the virtually unlimited Umpqua River to draw from. Much like
a master skeet shooter who uses a .410 to make the sport more
interesting, I have chosen to dry garden.
Few are this lucky. These days the majority of North Americans live
an urban struggle. Their houses are as often perched on steep,
thinly soiled hills or gooey, difficult clay as on a tiny fragment
of what was once prime farmland. And never does the municipal
gardener have one vital liberty I do: to choose which one-sixth of
an acre in his 14-acre "back yard" he'll garden on this year.
I was a suburban backyard gardener for five years before deciding to
homestead. I've frequently recalled this experience while learning
to dry garden. What follows in this chapter are some strategies to
guide the urban in becoming more water-wise.
Water Conservation Is the Most Important First Step
After it rains or after sprinkler irrigation, water evaporates from
the surface until a desiccated earth mulch develops. Frequent light
watering increases this type of loss. Where lettuce, radishes, and
other shallow-rooting vegetables are growing, perhaps it is best to
accept this loss or spread a thin mulch to reduce it. But most
vegetables can feed deeper, so if wetting the surface can be
avoided, a lot of water can be saved. Even sprinkling longer and
less frequently helps accomplish that. Half the reason that drip
systems are more efficient is that the surface isn't dampened and
virtually all water goes deep into the earth. The other half is that
they avoiding evaporation that occurs while water sprays through the
air between the nozzle and the soil. Sprinkling at night or early in
the morning, when there is little or no wind, prevents almost all of
this type of loss.
To use drip irrigation it is not necessary to invest in pipes,
emitters, filters, pressure regulators, and so forth. I've already
explained how recycled plastic buckets or other large containers can
be improvised into very effective drip emitters. Besides, drip tube
systems are not trouble free: having the beds covered with fragile
pipes makes hoeing dicey, while every emitter must be periodically
checked against blockage.
When using any type of drip system it is especially important to
relate the amount of water applied to the depth of the soil to the
crops, root development. There's no sense adding more water than the
earth can hold. Calculating the optimum amount of water to apply
from a drip system requires applying substantial, practical
intelligence to evaluating the following factors: soil water-holding
capacity and accessible depth; how deep the root systems have
developed; how broadly the water spreads out below each emitter
(dispersion); rate of loss due to transpiration. All but one of
these factors--dispersion--are adequately discussed elsewhere in
_Gardening Without Irrigation._
A drip emitter on sandy soil moistens the earth nearly straight down
with little lateral dispersion; 1 foot below the surface the wet
area might only be 1 foot in diameter. Conversely, when you drip
moisture into a clay soil, though the surface may seem dry, 18
inches away from the emitter and just 3 inches down the earth may
become saturated with water, while a few inches deeper, significant
dispersion may reach out nearly 24 inches. On sandy soil, emitters
on 12-inch centers are hardly close enough together, while on clay,
30-or even 36-inch centers are sufficient.
Another important bit of data to enter into your arithmetic: 1 cubic
foot of water equals about 5 gallons. A 12-inch-diameter circle
equals 0.75 square feet (A = Pi x Radius squared), so 1 cubic foot
of water (5 gallons) dispersed from a single emitter will add
roughly 16 inches of moisture to sandy soil, greatly overwatering a
medium that can hold only an inch or so of available water per foot.
On heavy clay, a single emitter may wet a 4-foot-diameter circle, on
loams, anywhere in between, 5 gallons will cover a 4-foot-diameter
circle about 1 inch deep. So on deep, clay soil, 10 or even 15
gallons per application may be in order. What is the texture of your
soil, its water-holding capacity, and the dispersion of a drip into
it? Probably, it is somewhere in between sand and clay.
I can't specify what is optimum in any particular situation. Each
gardener must consider his own unique factors and make his own
estimation. All I can do is stress again that the essence of
water-wise gardening is water conservation.
Optimizing Space: Planning the Water-Wise Backyard Garden
Intensive gardening is a strategy holding that yield per square foot
is the supreme goal; it succeeds by optimizing as many growth
factors as possible. So a raised bed is loosened very deeply without
concern for the amount of labor, while fertility and moisture are
supplied virtually without limit. Intensive gardening makes sense
when land is very costly and the worth of the food grown is judged
against organic produce at retail--and when water and nutrients are
inexpensive and/or available in unlimited amounts.
When water use is reduced, yield inevitably drops proportionately.
The backyard water-wise gardener, then, must logically ask which
vegetable species will give him enough food or more economic value
with limited space and water. Taking maritime Northwest rainfall
patterns into consideration, here's my best estimation:
Water-Wise Efficiency of Vegetable Crops
(in terms of backyard usage of space and moisture)
EFFICIENT ENOUGH
Early spring-sown crops: peas, broccoli, lettuce, radishes, savoy
cabbage, kohlrabi
Overwintered crops: onions, broccoli cauliflower,
cabbage, favas beans
Endive Kale
Garden sorrel
Indeterminate tomatoes
Giant kohlrabi
Parsley--leaf and root
heirloom summer squash (sprawly)
Pole beans
Herbs: marjoram, thyme, dill, cilantro, fennel, oregano
Root crops: carrots, beets, parsnips
MARGINAL
Brussels sprouts (late)
Potatoes
Determinate tomatoes
Rutabagas
Eggplant
Leeks
Leeks
Savoy cabbage (late)
Peppers, small fruited
INEFFICIENT
Beans, bush snap
Peppers, bell
Broccoli, summer
Radishes
Cauliflower
Scallions, bulb onions
Celery
Sweet corn
Lettuce
Turnips
Have fun planning your own water-wise garden!
More Reading
About the Interlibrary Loan Service
Agricultural books, especially older ones, are not usually available
at local libraries. But most municipal libraries and all
universities offer access to an on-line database listing the
holdings of other cooperating libraries throughout the United
States. Almost any book published in this century will be promptly
mailed to the requesting library. Anyone who is serious about
learning by reading should discover how easy and inexpensive (or
free) it is to use the Interlibrary Loan Service.
Carter, Vernon Gill, and Tom, Dale. _Topsoil and Civilization._
Norman, Okla.: University of Oklahoma Press, 1974.
The history of civilization's destruction of one ecosystem after
another by plowing and deforestation, and its grave implications for
our country's long-term survival.
Cleveland, David A., and Daniela Soleri. _Food from Dryland Gardens:
An Ecological, Nutritional and Social Approach to Small-Scale
Household Food Production. _Tucson: Center for People, Food and
Environment, 1991.
World-conscious survey of low-tech food production in semiarid
regions.
Faulkner, Edward H._ Plowman's Folly._ Norman, Okla.: University of
Oklahoma Press, 1943.
This book created quite a controversy in the 1940s. Faulkner
stresses the vital importance of capillarity. He explains how
conventional plowing stops this moisture flow.
Foth, Henry D. _Fundamentals of Soil Science. _Eighth Edition. New
York: John Wylie & Sons, 1990.
A thorough yet readable basic soil science text at a level
comfortable for university non-science majors.
Hamaker, John. D. _The Survival of Civilization._ Annotated by
Donald A. Weaver. Michigan/California: Hamaker-Weaver Publishers,
1982.
Hamaker contradicts our current preoccupation with global warming
and makes a believable case that a new epoch of planetary glaciation
is coming, caused by an increase in greenhouse gas. The book is also
a guide to soil enrichment with rock powders.
Nabhan, Gary. _The Desert Smells like Rain: A Naturalist in Papago
Indian Country. _San Francisco: North Point Press, 1962.
Describes regionally useful Native American dry-gardening techniques
Russell, Sir E. John. _Soil Conditions and Plant Growth. _Eighth
Edition. New York: Longmans, Green & Co., 1950.
Probably the finest, most human soil science text ever written.
Russell avoids unnecessary mathematics and obscure terminology. I do
not recommend the recent in-print edition, revised and enlarged by a
committee.
Smith, J. Russell. Tree Crops: a Permanent Agriculture. New York:
Harcourt, Brace and Company, 1929.
Smith's visionary solution to upland erosion is growing unirrigated
tree crops that produce cereal-like foods and nuts. Should sit on
the "family bible shelf" of every permaculturalist.
Solomon, Stephen J. _Growing Vegetables West of the Cascades.
_Seattle: Sasquatch Books, 1989.
The complete regional gardening textbook.
-------------------------. _Backyard Composting._ Portland, Ore.:
George van Patten Publishing, 1992.
Especially useful for its unique discussion of the overuse of
compost and a nonideological approach to raising the most nutritious
food possible.
Stout, Ruth. _Gardening Without Work for the Aging, the Busy and the
Indolent. _Old Greenwich, Conn.: Devin-Adair, 1961.
Stout presents the original thesis of permanent mulching.
Turner, Frank Newman. _Fertility, Pastures and Cover Crops Based on
Nature's Own Balanced Organic Pasture Feeds._ San Diego: Rateaver,
1975. Reprinted from the 1955 Faber and Faber, edition.
Organic farming using long rotations, including deeply rooted green
manures developed to a high art. Turner maintained a productive
organic dairy farm using subsoiling and long rotations involving
tilled crops and semipermanent grass/herb mixtures.
ven der Leeden, Frits, Fred L. Troise, and David K. Todd. _The Water
Encyclopedia, Second Edition. _Chelsea, Mich.: Lewis Publishers,
1990.
Reference data concerning every possible aspect of water.
Weaver, John E., and William E. Bruner. _Root Development of
Vegetable Crops._ New York: McGraw-Hill, 1927.
Contains very interesting drawings showing the amazing depth and
extent that vegetable roots are capable of in favorable soil.
Widtsoe, John A. _Dry Farming: A System of Agriculture for Countries
Under Low Rainfall. _New York: The Macmillan Company, 1920.
The best single review ever made of the possibilities of dry farming
and dry gardening, sagely discussing the scientific basis behind the
techniques. The quality of Widtsoe's understanding proves that newer
is not necessarily better.
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