June 02, 2006

Dry-country gardening

For years, all the organic-gardening books assumed that you lived east of the 100th meridian. You wanted raised beds for vegetables, you wanted to correct the acidity of your soil, you worried about drainage.

Gardeners in southern Colorado and other Southwestern states have a different set of issues. Our conditions are based much more on altitude, and precipitation patterns vary widely.

In recent years, more localized guides have been published, such as Lisa Rayner's Growing Food in the Southwest Mountains. Based in Flagstaff, Ariz., she assumes a volcanic soil, however, whereas we are coping with "Holderness silt loam," associated with an annual precipitation of 18 inches (45 cm)--although this year I would say that we have had half of that.

"Permeability is slow, and the available water capacity is high. The surface and subsurface layers are neutral, and the underlying material is moderately alkaline" (Soil Conservation Service, Soil Survey of Pueblo Area, Colorado, 1973)

The sun beats down, the wind blows, and daily temperatures typically vary widely, say from 45 to 85 F (10-30 C) on a summer day.

We can't even learn gardening from indigenous cultures, since they were hunter-gatherers, although the archaic "Plains Woodland" culture apparently grew some crops along stream beds on the out High Plains. But when they got horses in the 17th century, they said, "Forget the beans and squash" and became buffalo hunters.

We can learn some tricks from the sedentary Anasazi people who lived further west, however. Although we follow Ruth Stout's approach and mulch heavily with pine needles, which are only a few steps away, M. has done some mulching the Anasazi way--with pebbles. It actually works: they reflect the sun and keep the soil surface damp.

Good soil, as the Bodios point out, has to be built.

Starting small seeds under burlap sheets and camouflage netting
Another technique that Rayner also mentions is the buried plastic jug, pierced with dozens of small holes. The gallon jugs that hold vinegar work well, being thicker-walled than milk jugs.

Bury it up to its neck and set plants right next to it. Then fill the jug with a hose or bucket and funnel. "Permeability is slow," but this way your water soaks in below the surface. (The original technique involved unglazed clay pots.)

The only way to start some annual plants from seed is to cover the beds with burlap or jute sacking. In the photo, I am also using some military-surplus camouflage netting, which we also use for shadecloth in July and August.

1 comment:

Mary Strachan Scriver said...

I appreciate this, Chas, as my conditions are similar to yours. I inherited peonies which are not doing well this year and wild geranium which is rampant. But I may have managed to established some hollyhocks and the Explorer series Canadian rose looks good this time. It's still pretty much only a sprig.

I'm going to try checkerboarding cement stepping stones with random small bulbs like the glacier lilies and frittilaries that are native and a big patch of camas.

This total variability in weather patterns from one year to the next rather confounds me. One year (this one) May is bright and wet while June is dark and dry -- the next year the opposite.

My overall principle is to eliminate grass and straight lines -- which is the exact opposite of the goals of my neighbors! But the other day someone said it looked like an English garden, sort of, which made me very happy.

Prairie Mary