FRC Forums Highlighted Post of the Week

This week is a great book review or synopsis, about a book by
Steve Solomon called “Gardening Without Irrigation (or not much anyway)”

Gardening Without Irrigation- Part1: The Secret of Available Moisture

Steve Solomon’s book “Gardening Without Irrigation (or not much anyway)”; At first, I did not think it would be too useful in out “rainy” eastern climate but the drought this year makes me think other wise. 230gr

This is essentially a story of a man, survivalist at heart, who moved his family from Michigan to a 5 acres homestead in Oregon in a lovely, grassy valley. To feed his family, he sets up raised beds and intensive (square foot) gardening, which had worked so well back east. He runs into an irrigation problem unlike anything he had anticipated and nearly looses the garden crops he was depending on which were sustained by watering all night, five or six nights a week, with a single, 2-1/2 gallon-per-minute sprinkler moved from place to place.

Eventually, realizing his vulnerability, he is forced to abandon the homestead and move. Yet he knows that the Indian peoples produced crops without irrigation and he sets out to find out how and to adapt it (if possible) to our current vegetables. He grew two gardens side-by-side: a large "dry" garden and another large one intensive style, on raised beds with lots of irrigation to feed his family and act as a control. Eventually, he discovered a method for growing a lush, productive vegetable garden on deep soil with little or no irrigation, in spite of 8 to 12 virtually dry weeks every summer by adapting Native Americans of the Southwest and the highlands of Peru grew remarkable desert gardens, with little or no water, in areas of only 8 to 12 inches of rainfall.

He found:
1. some types of vegetable could be grown with out irrigation at all
2. some needed irrigation to simply survive
3. some benefited from a few minimally metered-out applications of fertilizer enriched watering ("fertigation")
4. some showed no increase in yield with fertigation.
5. there is water already present in the soil and, by creatively using and conserving this moisture, gardeners can go through an entire summer without much, if any, irrigation

The Secret of Available Moisture
Sandy….1.0 inches of water per foot of soil
Loam…..2.0 inches of water per foot of soil
Clay……2.7 inches of water per foot of soil

If you get a rainy or snowy winter, by spring the soil is holding all the moisture it can. Summer rains come rarely and do not penetrate deeply so it quickly evaporates from the surface few inches without recharging deeper layers. While the hot sun does dry out the surface inches, down 6 inches or so, there will be almost as much water present in September as there was in April. Once a thin surface layer is completely desiccated, be it loose or compacted, virtually no further loss of moisture can occur except certain kinds of very heavy clays that form deep cracks. If the cracks are filled with dust by surface cultivation, even this soil type ceases to lose water. If a vegetable’s root systems can grow deep and wide enough and given permeable soil with enough space to grow, it can utilize this available moisture to sustain it’s growth.
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Gardening Without Irrigation- Part2: Helping Plants to Need Less Irrigation
How Plants Obtain Water
Plants acquire water and minerals through their actively growing, tender root tips and almost microscopic root hairs close to the tip absorb most of the plant's moisture while the parts behind the tip cease to be effective. The plant is far better off to aggressively seek new water in unoccupied soil than to wait for the soil its roots already occupy to be recharged. Once a leaf canopy forms, plant growth slows markedly. Adding a little more fertilizer helps but the rate of growth never equals that of younger plants. The unseen competition for root room slows them down and allocating more area allows vegetables to get larger, yield longer and allows reduced irrigation frequency. How long available soil water will sustain a crop is determined by how many plants are drawing on the reserve, how extensively their root systems develop, and how many leaves are transpiring the moisture. If there are no plants, most of the water will stay unused in the barren soil through the entire growing season. Most gardens can yield abundantly without any rain at all if only we reduce competition for available soil moisture, judiciously fertigate some vegetable species, and practice a few other water-wise tricks. Lowering plant density will lower the yield but not proportionately. A plant density one-eighth of intensive gardening results in a yield about half as great.

Helping Plants to Need Less Irrigation
1. The most obvious step is thorough weeding.
2. Keep the surface fluffed up with a rotary tiller or hoe during April and May, to break its capillary connection with deeper soil and accelerate the formation of a dry dust mulch.
3. Should rain during summer, hoe or rotary till a day or two later and again help a new dust mulch to develop.
4. Loosen the soil! Compacted soil acts as a mechanical barrier to root system expansion and many vegetable species are capable of reaching 4, 5, and 8 eight feet down to find moisture and nutrition.
5. Double digging by trenching out 12 inches and mixing the next foot with organic matter for a depth of nearly 24 inches to 10% (rotary tilling only 6 or 7) very sandy soil’s water-holding ability in the top 2 feet could be doubled to 2 extra inches of water per foot of soil; enough to increase the time between heavy irrigations by 10 days.
6. When roots decay, fresh organic matter can be left deep in the soil, once the subsoil has been mechanically fractured, green manure crops can maintain the openness of the subsoil; sweet clover, may go down 8 feet, red clover, the top 5 feet, densely sown carrots, parsley, and parsnip are helpful.
7. Permanent mulching with organic matter does not reduce moisture loss any better than dust mulching and frequently hoeing of weeds will make the top inch or two of earth dry and powdery.
8. A mulch of dry hay, grass clippings, or leaves, will also retard moisture loss, especially right at the surface, however, the overall moisture loss is about the same.
a. permanent thick mulch quickly breeds many slugs, earwhigs, and sowbugs
b. that maintaining it for more than one year makes vegetable gardening very difficult.
c. Unless you live in an area with a long winter freeze to set populations back.
9. Windbreaks are also helpful in reducing evaporation.
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Gardening Without Irrigation- Part 3: Dry garden feeding & seed sprouting

Fertilizing, Fertigating and Foliar Spraying
1. Fertilizing, before sowing or transplanting large species like tomato, squash or big brassicas, dig out a small 12 inch deep pit, blend in two cups of organic fertilizer with the soils at the bottom, then fill the hole back in to concentrate fertility at 18 to 24 inches below the seedlings.
2. Foliar feeding, dilute soluble nutrients sprayed on plant leaves, is rapidly taken in but the growth response lasts for 3 to 5 days so must be applied weekly.
a. Use caution, spinach, beet, and chard leaves may be damaged by even half-strength applications.
b. The cabbage family leaf surfaces are waxy makes sprays run off mix a little Soap.
c. The poorest foliar sprays are organic, poor in phosphorus & calcium but the most useful is 1/2 to 1 tablespoon each of fish emulsion and liquid seaweed concentrate per gallon of water.
d. Chemical fertilizers, water-soluble, the best is Rapid-Gro or Dyna-Gro 7-9-5, then Peters 20-20-20, if you dissolve calcium nitrate into a solution just before spraying; all these chemicals are mixed at about 1 tablespoon per gallon.
3. Fertigation, for maximizing yield while minimizing water use, every two to four weeks beginning late in June and continue periodically through early September.
a. Use six or seven plastic 5-gallon "drip system" buckets, setting one by each plant, and fill them all with a hose, doing 12 or 14 plants each and rotate through them all more or less every three weeks.
b. Make a 5 gallon drip bucket by drilling a 3/16-inch hole through the side about 1/4-inch up from the bottom.
c. Placed the bucket so that the fertilized water drains out close to the stem of a plant, then filled with liquid fertilizer solution.
d. It takes 5 to 10 minutes for 5 gallons to pass through a small opening, and because of the slow flow rate, water penetrates deeply into the subsoil without wetting much of the surface.
e. Each fertigation makes the plant grow very rapidly for two to three weeks.
f. Organicfertigate with fish emulsion and seaweed at 1/2 to 1 tablespoon each per gallon of water with weak compost/manure tea.
Vegetables That:
Like foliars
Asparagus Carrots Melons Squash
Beans Cauliflower Peas Tomatoes
Broccoli Brussels sprouts Cucumbers
Cabbage Eggplant Radishes
Kale Rutabagas Potatoes

Don't like foliars
Beets Leeks Onions Spinach
Chard Lettuce Peppers

Like fertigation
Brussels sprouts Kale Savoy cabbage
Cucumbers Melons Squash
Eggplant Peppers Tomatoes

Sprouting Seeds Without Watering
Small seeds need to grow in light, fluffy soil but tillage breaks capillary connections that draw up subsoil moisture until the fluffy soil resettles. In recently tilled earth, successfully sprouting small seeds in warm weather is dicey without frequent watering or reestablishing capillarity moisture below sprouting seeds so that moisture held deeper in the soil rises to replace that lost from surface layers, reducing or eliminating the need for watering. Simple foot pressure can restored capillarity, and during the night, fresh moisture replaced what had evaporated. This simple technique helps start everything except carrots and parsnips (which must have completely loose soil to develop correctly). Compress the soil below the seeds and then cover the seeds with a mulch of loose, dry soil. Sprouting seeds then rest atop damp soil and will sprout, root and leaf very quickly.

Techniques to reestablish capillarity after tilling.
1. Push planter: first compacts the tilled earth with its front wheel, cuts a furrow, drops the seed, and then with its drag chain pulls loose soil over the furrow.
2. Wheelbarrow, pull a lightly loaded, down the row to press down a wheel track, sprinkled seed on that compacted furrow, and then pulled loose soil over it.
3. Handmade Footprints-
a. sow large brassicas, squash, melon and cucumber, in clumps on hills above a fertilized, double-dug spot, about 18 inches square, deeply dig in complete organic fertilizer.
b. In the center of the fluffed-up mound, punch down a depression to reestablish capillarity by having firm soil under a shallow, fist-sized depression, then a pinch of seed is sprinkled atop this depression and covered with fine earth and good germination without watering.

How to Fluid Drill Seeds
1. Place the seeds in a half-pint mason jar, cover with a square of plastic window screen held on with a strong rubber band, soak the seeds overnight, and then drain them first thing in the morning.
2. Gently rinse the seeds with cool water two or three times daily until the root tips begin to emerge.
3. As soon as this sign appears, the seed must be sown, because the newly emerging roots become increasingly subject to breaking off as they develop and soon form tangled masses.
4. Presprouted seeds may be gently blended into some crumbly, moist soil and this mixture gently sprinkled into a furrow and covered.

Starch gelatin fluid drilling
If the sprouts are particularly delicate or, as with carrots, you want a very uniform stand, disperse the seeds in a starch gelatin for fluid drilling.
1. Heat one pint of water to the boiling point and dissolve in 2 to 3 tablespoons of ordinary cornstarch.
2. Let the mixture cool until it becomes a soupy gel.
3. Gently mix this cool starch gel with the sprouting seeds, making sure the seeds are uniformly blended.
4. Pour the mixture into a 1-quart plastic bag and, scissors in hand, go out to the garden.
5. Prepared a furrow with capillarity restored and cut a /4 inch in diameter hole in one lower corner of the bag.
6. Walk quickly down the row, dribbling a mixture of gel and seeds into the furrow, then cover.
7. The presprouted seeds come up days sooner, the root will penetrating moist soil long before the shoot emerges and the stand of seedlings will be very uniformly spaced, be easier to thin and that you need quite a bit less seed per length of row.

Nursery Bed alternative
1. Instead of trying to irrigate the entire area, seedlings are first grown in irrigated nurseries for transplanting after the rains come back.
2. If desperately short of water, locate the nursery where it gets only morning sun and sow a week or 10 days earlier to compensate for the slower growth.
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