Gardening with Less Water by David Bainbridge

The Big Idea: Super-efficient irrigation techniques (ollas, clay pipes, terraces, check dams, swales) have been used for thousands of years.

Drip irrigation has helped increase water-use efficiency in gardens and farms, but drip systems are for the well-off.

The key to minimizing water use is to get water to the plant just as it is needed, with little or no loss to evaporation and runoff.

Irrigation systems that automatically self-regulate, such as buried clay pots, porous capsules, porous clay pipes, and capillary wicks, are particularly efficient because the water flow rate varies with plant water demand.

Deep pipes can be best for trees and shrubs, buried clay pots may be best for spreading crops such as melons, and porous hoses may be best for row crops such as carrots.

Buried clay pot (also called pitcher or olla) irrigation is one of the most efficient systems known, thought to have originated in China thousands of years ago.

The olla should be buried up to the neck. A small lid or a rock can be placed over the opening.

Roots of older plants may grow thick around the pot, but in desert studies, this did not hurt long-term survival.

Clay pots must be porous, not glazed, and free of wax, paint, or other impervious coatings.

Snails and slugs are easy to manage with clay pot irrigation. They tend to collect at the pot / soil seam or crawl into the pot as it dries out and can easily be removed and fed to the ducks.

Buried clay pots are usually filled individually, but if you will be away often or don’t want to bother filling them by hand, they can be connected to a reservoir or water system.

Porous capsule irrigation is a modern adaptation of buried clay pot irrigation.

A plastic sports bottle makes a handy reservoir for a porous capsule.

Standard red clay garden terra-cotta pots and pot bases make good porous capsules when glued together.

Deep pipe irrigation uses a vertical pipe to move water into deeper soil where it is safe from evaporation.

I prefer 2-inch diameter PVC pipe or conduit because it’s easy to fill from a water jug.

Deep pipes work well for starting orchards and for planting cottonwood poles in riparian areas where very deep watering is needed.

Pipes can often be removed 1 or 2 years after the trees or shrubs are well established.

Converting an established shrub or tree from surface to deep pipe irrigation should be done gradually to enable a shift in root development.

Porous hose (ie soaker hose) lets water seep out through pores in a buried hose.

Porous hoses are typically made of recycled rubber, with the water release rate depending on pore size and water pressure.

For trees and shrubs, make a loop of porous hose around the plant.

Porous hose can be looped around trees to improve water distribution and root growth.

Give priority to the native plants from your region.

Choose varieties that are dryland adapted.

Replace your lawn.

Plant in blocks instead of rows.

Keep your soil healthy and uncompacted.

Check your soil’s drainage.

Use mulch.

Consider irrigating with greywater.

Ten inches of rain on a 1,000-square-foot roof will provide about 6,000 gallons of water.

The lowest-cost tank is probably homemade with ferrocement.

One of the best learning experiences is watching and experimenting with various rainwater harvesting systems during rainstorms.

Cross-slope collection ditches or swales may be interspersed to collect excess water on the slope during severe storms.

Vertical mulching consists of placing straw, sticks, or brush upright in the soil to help move water deeper into the ground.

Check dams have been used for millennia to protect fields and help capture rainwater.

They also allow the sediment to drain, and are more likely to grow vegetation that can further stabilize the gully.

Terracing is one of the most common responses to erosion and runoff retention.

Many terraces in China have been used continuously for thousands of years.

Raised beds, developed for wet areas, are more widely known and promoted, but waffle-like sunken beds work better in dry lands.

Comments are closed.