Introduction
Starting a New Gardening Era
First, you should know why a maritime Northwest
raised-bed gardener named Steve Solomon became worried about his dependence on irrigation.
I'm from Michigan. I moved to Lorane,
Oregon, in April 1978 and homesteaded on 5 acres in what I thought at the time was
a cool, showery green valley of liquid sunshine and rainbows. I intended to put in
a big garden and grow as much of my own food as possible.
Two months later, in June, just as
my garden began needing water, my so-called 15-gallon-per-minute well began to falter,
yielding less and less with each passing week. By August it delivered about 3 gallons
per minute. Fortunately, I wasn't faced with a completely dry well or one that had
shrunk to below 1 gallon per minute, as I soon discovered many of my neighbors were
cursed with. Three gallons per minute won't supply a fan nozzle or even a common
impulse sprinkler, but I could still sustain my big raised-bed garden by watering
all night, five or six nights a week, with a single, 2-1/2 gallon-per-minute sprinkler
that I moved from place to place.
I had repeatedly read that gardening
in raised beds was the most productive vegetable growing method, required the least
work, and was the most water-efficient system ever known. So, without adequate irrigation,
I would have concluded that food self-sufficiency on my homestead was not possible.
In late September of that first year, I could still run that single sprinkler. What
a relief not to have invested every last cent in land that couldn't feed us.
For many succeeding years at Lorane,
I raised lots of organically grown food on densely planted raised beds, but the realities
of being a country gardener continued to remind me of how tenuous my irrigation supply
actually was. We country folks have to be self-reliant: I am my own sanitation department,
I maintain my own 800-foot-long driveway, the septic system puts me in the sewage
business. A long, long response time to my 911 call means I'm my own self-defense
force. And I'm my own water department.
Without regular and heavy watering
during high summer, dense stands of vegetables become stunted in a matter of days.
Pump failure has brought my raised-bed garden close to that several times. Before
my frantic efforts got the water flowing again, I could feel the stressed-out garden
screaming like a hungry baby.
As I came to understand our climate,
I began to wonder about complete food self-sufficiency. How did the early
pioneers irrigate their vegetables? There probably aren't more than a thousand homestead
sites in the entire martitime Northwest with gravity water. Hand pumping into hand-carried
buckets is impractical and extremely tedious. Wind-powered pumps are expensive and
have severe limits.
The combination of dependably rainless
summers, the realities of self-sufficient living, and my homestead's poor well turned
out to be an opportunity. For I continued wondering about gardens and water, and
discovered a method for growing a lush, productive vegetable garden on deep soil
with little or no irrigation, in a climate that reliably provides 8 to 12 virtually
dry weeks every summer.
Gardening with Less Irrigation
Being a garden writer, I was on
the receiving end of quite a bit of local lore. I had heard of someone growing unirrigated
carrots on sandy soil in southern Oregon by sowing early and spacing the roots 1
foot apart in rows 4 feet apart. The carrots were reputed to grow to enormous sizes,
and the overall yield in pounds per square foot occupied by the crop was not as low
as one might think. I read that Native Americans in the Southwest grew remarkable
desert gardens with little or no water. And that Native South Americans in the highlands
of Peru and Bolivia grow food crops in a land with 8 to 12 inches of rainfall. So
I had to wonder what our own pioneers did.
In 1987, we moved 50 miles south, to
a much better homestead with more acreage and an abundant well. Ironically, only
then did I grow my first summertime vegetable without irrigation. Being a low-key
survivalist at heart, I was working at growing my own seeds. The main danger to attaining
good germination is in repeatedly moistening developing seed. So, in early March
1988, I moved six winter-surviving savoy cabbage plants far beyond the irrigated
soil of my raised-bed vegetable garden. I transplanted them 4 feet apart because
blooming brassicas make huge sprays of flower stalks. I did not plan to water these
plants at all, since cabbage seed forms during May and dries down during June as
the soil naturally dries out.
That is just what happened. Except
that one plant did something a little unusual, though not unheard of. Instead of
completely going into bloom and then dying after setting a massive load of seed,
this plant also threw a vegetative bud that grew a whole new cabbage among the seed
stalks.
With increasing excitement I watched
this head grow steadily larger through the hottest and driest summer I had ever experienced.
Realizing I was witnessing revelation, I gave the plant absolutely no water, though
I did hoe out the weeds around it after I cut the seed stalks. I harvested the unexpected
lesson at the end of September. The cabbage weighed in at 6 or 7 pounds and was sweet
and tender.
Up to that time, all my gardening had
been on thoroughly and uniformly watered raised beds. Now I saw that elbow room might
be the key to gardening with little or no irrigating, so I began looking for more
information about dry gardening and soil/water physics. In spring 1989, I tilled
four widely separated, unirrigated experimental rows in which I tested an assortment
of vegetable species spaced far apart in the row. Out of curiosity I decided to use
absolutely no water at all, not even to sprinkle the seeds to get them germinating.
I sowed a bit of kale, savoy cabbage,
Purple Sprouting broccoli, carrots, beets, parsnips, parsley, endive, dry beans,
potatoes, French sorrel, and a couple of field cornstalks. I also tested one compactbush
(determinate) and one sprawling (indeterminate) tomato plant. Many of these vegetables
grew surprisingly well. I ate unwatered tomatoes July through September; kale, cabbages,
parsley, and root crops fed us during the winter. The Purple Sprouting broccoli bloomed
abundantly the next March.
In terms of quality, all the harvest
was acceptable. The root vegetables were far larger but only a little bit tougher
and quite a bit sweeter than usual. The potatoes yielded less than I'd been used
to and had thicker than usual skin, but also had a better flavor and kept well through
the winter.
The following year I grew two parallel
gardens. One, my "insurance garden," was thoroughly irrigated, guaranteeing
we would have plenty to eat. Another experimental garden of equal size was entirely
unirrigated. There I tested larger plots of species that I hoped could grow through
a rainless summer.
By July, growth on some species had
slowed to a crawl and they looked a little gnarly. Wondering if a hidden cause of
what appeared to be moisture stress might actually be nutrient deficiencies, I tried
spraying liquid fertilizer directly on these gnarly leaves, a practice called foliar
feeding. It helped greatly because, I reasoned, most fertility is located in the
topsoil, and when it gets dry the plants draw on subsoil moisture, so surface nutrients,
though still present in the dry soil, become unobtainable. That being so, I reasoned
that some of these species might do even better if they had just a little fertilized
water. So I improvised a simple drip system and metered out 4 or 5 gallons of liquid
fertilizer to some of the plants in late July and four gallons more in August. To
some species, extra fertilized water (what I call "fertigation") hardly
made any difference at all. But unirrigated winter squash vines, which were small
and scraggly and yielded about 15 pounds of food, grew more lushly when given a few
5-gallon, fertilizer-fortified assists and yielded 50 pounds. Thirty-five pounds
of squash for 25 extra gallons of water and a bit of extra nutrition is a pretty
good exchange in my book.
The next year I integrated all this
new information into just one garden. Water-loving species like lettuce and celery
were grown through the summer on a large, thoroughly irrigated raised bed. The rest
of the garden was given no irrigation at all or minimally metered-out fertigations.
Some unirrigated crops were foliar fed weekly.
Everything worked in 1991! And I found
still other species that I could grow surprisingly well on surprisingly small amounts
of water[--]or none at all. So, the next year, 1992, I set up a sprinkler system
to water the intensive raised bed and used the overspray to support species that
grew better with some moisture supplementation; I continued using my improvised drip
system to help still others, while keeping a large section of the garden entirely
unwatered. And at the end of that summer I wrote this book.
What follows is not mere theory, not
something I read about or saw others do. These techniques are tested and workable.
The next-to-last chapter of this book contains a complete plan of my 1992 garden
with explanations and discussion of the reasoning behind it.
In Water-Wise Vegetables I assume
that my readers already are growing food (probably on raised beds), already know
how to adjust their gardening to this region's climate, and know how to garden with
irrigation. If you don't have this background I suggest you read my other garden
book, Growing Vegetables West of the Cascades, (Sasquatch Books, 1989).
Steve Solomon