Homestead Gardener Q&A with Jay Quade

University of Arizona geologist Jay Quade explains how to garden in Tucson’s tough soil.

November 1, 2014

HomesteadHomestead Q&AIssue 9: November/December 2014

If caliche is “the kiss of death” for a garden, as Jay Quade argues, how does he grow 20 fruitful trees and more than 100 food plants, including corn, on that kind of rocky ledge?

It’s all about correcting the soil, says Quade, a geologist at the University of Arizona. And that can be costly. “But it’s good therapy and exercise. And your food tastes better.”

Jay and Barbra Quade, a family therapist, have gardened, pesticide free, for 15 years on a West University lot of 120 by 60 feet. Almost every unoccupied inch is planted. “We’re over 50 percent food sufficient,” Jay says. “Sixty percent,” says Barbra. “This is a real urban farm,” Jay adds.

What’s up with Tucson soil?

There are two types, two extremes of our native soil. Type 1 is down near the active washes, where there’s loose, sandy alluvium. It hasn’t been compacted, hasn’t built up salt. I call it the young soil. It’s deposited in the flood plains. Young soil can be found by the Santa Cruz, for example, at low elevations.

Stephen-Eginoire_Homestead_Edible–Baja–Ariona_01-0002Type 2 is the old soil, up in central Tucson’s hills, at the University of Arizona, say, and in West University. It’s been sitting out forever, and now it’s all caliche and clay, on the topographic high points, up on the old terraces above the ancient Santa Cruz. Soil isn’t like wine. Soil gets worse as it gets older.

Once there was clay on top, but the developers pushed it away to level the home site, so my backyard is mostly caliche at the surface. That’s the kiss of death for gardening. You replace that.

Can native clay soil go in the new mix?

The native clay is fine, and we put that aside. For the caliche, we dug 8 x 10 x 3 foot beds mainly with a backhoe. I jackhammered out the rest of the caliche. Soak it overnight, really soak it, and caliche comes right out. Then, we put in a mixture of one third native clay, a third river sand, and a third compost, our own and some purchased compost.

How did your earliest garden work out?

Back then, we had winter greens, lettuce, arugula, mustard, coriander, almost all the temperate herbs. But the soil wasn’t good for root vegetables, like beets, turnips, fennel, carrots. We were gardening on the native soil, on the fly. We ran with what we had, and the yield decreased the second year. Native soil is good for one year, then it needs amendment, a commercial fertilizer.

Stephen-Eginoire_Homestead_Edible–Baja–Ariona_01-0000You used commercial compost?

Yes, starting three years ago. And we bought it at several places – I don’t want to say where. But you have to be careful. It was too salty. Buyer beware.

At Acme Sand and Gravel, they provide a chemical analysis of their soils and were quite knowledgeable. Don’t buy commercial compost in big lots until you have given it a try.

When do you start your winter garden?

We planted in early September. Before that, the leaf cutter ants would decimate the sprouting greens.

How much do you experiment?

A lot. You try multiple varieties to see what takes. That’s vital if you are serious about this. And it’s important to rotate crops by location. We experiment constantly with that.

We tried Early Girl tomatoes. Not so good. Now we plant a mix of cherry tomatoes. They are prolific and taste good. We have good success with Russian tomatoes.

We have an unusual climate and seeds from chain stores aren’t always appropriate. For seeds, you should look to areas with climates similar to ours. Like Yunnan in China. Turkey. Italy. North Africa and Spain. Wherever it really heats up in the summer. Russian summers are like our winters.

Stephen-Eginoire_Homestead_Edible–Baja–Ariona_01-0001Any failures?

Many. For example, two years we had failures with Kentucky Wonder (a pole green bean) and Kentucky Blue Beans. They aren’t for this climate. Now we plant some Chinese beans, from Yunnan, China, which has weather similar to here in the monsoons. They go crazy here. And now in September, we plant the Asparagus Yardlong bean, from Gourmet Seed International in New Mexico.

A conspicuous failure was cucumbers, squash, and melons; all had infestations, of worms and aphids. A white worm eats the stem from the inside. You can slice open the stem and take out the worm, and the plant limps along, but that’s too much.

Ford Burkhart has called Tucson home for going on 70 years; his 1917 bungalow has a tree he planted in 1947.

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