When to Plant Tomatoes in Arizona?

You will be proud to show off your homegrown Arizona tomatoes.

Tomato lovers agree that nothing can match the flavor of a ripe, homegrown tomato. Tomatoes are a garden vegetable that is easy to grow, even in Arizona's dry climate.

Time Frame

Arizona's climate varies drastically from the north country to the low desert. Tomatoes are temperature-sensitive, so plant after the last threat of frost, regardless of your location. Frost is unlikely in the Phoenix area after mid-February, while northern Arizona experiences winters similar to areas in the northern U.S. and can see frost through May.

Planting

Start tomatoes indoors during the off-season. Plant tomato seeds in planting pots under 1/4 inch of fertile soil. Keep the tray near a south-facing window so it receives maximum sun exposure all day. Transplant the plants outdoors after they grow their third set of true leaves. Place pots outside for a few hours each day a couple weeks before transplanting to allow the plants to acclimate to outdoor sunlight and temperature conditions.

Considerations

Gardeners in the low desert are often able to experience two tomato seasons: in early spring and in fall. Fruit usually cannot set in temperatures above 95 degrees Fahrenheit, however, so mid-summer harvests are not practical in the desert regions.

References

• Ontario Ministry of Agriculture: The Effect of Extreme Temperatures on the Tomato and Pepper Crop
• University of Arizona Extension: Arizona Plant Climate Zones
• Victory Seeds: Growing Tomatoes from Seed