Gardening in Arizona

Everything we have worked out for Arizona: what to plant and when, which varieties finish in time, the pests that actually turn up here, and the jobs that pay off month by month. We also cover the rest of the property, from lawns and soil to home care and energy, because a garden rarely stops at the vegetable bed.

The numbers first, because everything else follows from them. Measured at the weather station in Phoenix, the last spring freeze falls around no freeze in most years; a rare cold snap can bring 32F between late December and mid January and the first fall freeze falls around no reliable fall freeze; see the note, USDA zones 4b-10b, 8,014 growing degree days in the year.

Heat, not frost, is what shortens the season here: above 86 °F tomato pollen goes sterile, so growers run a spring crop and an autumn one rather than a single long season. Garlic is the awkward one: only 0 weeks below 40 °F, where it needs six to split into cloves. Chill the cloves before planting, or grow a softneck type.

Elsewhere on the property in Arizona: the pests that turn up here.

Figures from NOAA's 1991-2020 climate normals. A state is not one climate: elevation, a large lake or the coast can move these dates by two weeks either way, so check your own county with the extension service before you spend money.

What Eats Onion in Arizona, and When

Golden onions freshly harvested and arranged on weathered wood with a vegetable field and wooden crate visible in the background.

University of Arizona Cooperative Extension documents seven insects that actually feed on onion here, out of a longer list of garden pests it tracks…

What Eats Corn in Arizona, and When

A brown caterpillar, likely a corn earworm, rests on a developing ear of corn with green husks and silks.

University of Arizona Cooperative Extension documents ten garden pests active on vegetable crops in the state, but only about half of them have any…

What Eats Pumpkin in Arizona, and When

A mature orange pumpkin grows on the vine in a garden patch with surrounding foliage and soil.

Nine pests documented for Arizona gardens actually feed on pumpkin: aphids, beet leafhopper, false chinch bug, grasshoppers, green fruit beetle, spider…

What Eats Potato in Arizona, and When

A striped Arizona potato beetle crawls across a green potato plant leaf in a garden setting.

The University of Arizona Cooperative Extension documents eight potato-relevant pests active in the state: aphids, beet leafhopper, false chinch bug…

What Eats Pepper in Arizona, and When

Mature red chili peppers hanging from a plant in a sunlit vegetable garden with blurred garden rows visible in the background.

Nine pests show up on University of Arizona Cooperative Extension’s list for garden crops in the low desert, but only some of them actually bother a…

What Eats Parsnip in Arizona, and When

A frost-covered parsnip root lies on frozen soil with dormant plants visible in the winter garden background.

In Arizona’s low desert, parsnips face a short list of documented feeders: aphids, beet leafhoppers, false chinch bugs, grasshoppers, spider mites, and…