August Planting Guide for Arizona’s Low Desert

By: Angela Judd | July 31, 2024

Are you wondering what to plant and harvest in August in Arizona? I’ll show you which seeds to start indoors and what you can plant outside in August. It is still hot in the Phoenix Valley, but if you want another round of warm-season crops, August is a good time to plant. It’s also an important month for starting seeds indoors.

For a printable checklist and information about August gardening tasks for the low desert, read this article. The low desert includes elevations below 3500 ft in the Southwest, such as the Phoenix and Tucson metro areas.

What to Plant and Harvest in August Low Desert of Arizona

Article Outline:

What to Do Before You Plant During August
What Can You Harvest in August in The Low Desert?
What’s Blooming in August?
What to Plant Outside in August in Arizona: Vegetables, Herbs & Fruit
Which Seeds to Start Indoors in August in Arizona: Vegetables, Herbs & Fruit
What to Plant Outside in August in Arizona: Flowers
Which Seeds to Start Indoors in August in Arizona: Flowers

What to Do Before You Plant During August in Arizona

As you decide what to plant in August (and upcoming months) in your low desert garden, think about what you enjoy growing the most—what do you most look forward to in the garden? Which foods taste best from the garden? What do you love having easy access to?

Take a look at your available space. A significant planting window for cool-season crops will open in mid-September and October, so be sure to leave some room for them!

By planting in August, you’re setting yourself up for a bountiful harvest of warm-season crops like tomatoes, squash, cucumbers, and corn, which can sometimes struggle because it gets hot so quickly in the spring.

August Gardening Tasks for Low Desert Arizona Gardens

Prepare beds for planting (this post tells you how). Add compost, worm castings, and other organic matter to the soil.
If your garden hasn’t been growing well, consider having your soil tested. I use this test kit from Amazon. Based on the soil test, add a balanced fertilizer if needed.
Take time to harden off your seedlings correctly so they can adjust to the heat. Learn more in this article.
Provide extra shade and water for new plantings.
For a printable checklist of garden tasks to do in August, read this post.

Want more information about gardening in Arizona? This blog post shares seven tips for how to grow a vegetable garden in Arizona.

What Can You Harvest in August in the Low Desert of Arizona?

We can garden year-round here in the low desert, and it seems there is always something to plant and harvest. Weather patterns vary, and some years higher than average heat and lack of rain can make gardening more challenging. However, If you’re following my planting guide, here are some of the vegetables it’s possible to harvest during August. I’d love for you to leave a comment and let me know what you’re harvesting right now.

(click on the link to read “How to Grow” articles about each crop)

Vegetables:

Amaranth, Armenian Cucumbers, Asparagus Beans, Beans, Borlotti Beans, Butternut Squash, Cucumbers, Eggplant, Malabar spinach, Okra, Peppers, Sunflower Seeds, Summer Squash, Tomatillos, Tomatoes

Herbs:

Basil, Dill Seeds, Lemongrass, Lemon Balm, Lemon Verbena, Mint, Oregano, Parsley Seeds, Sage, Stevia, Rosemary, Thyme

Fruit:

Apples, Blackberries, Cantaloupe, Chichiquelite, Figs, Grapes, Ground Cherries, Passionfruit, Watermelon

Which Flowers Bloom in August in the Low Desert of Arizona?

It’s hard to believe anything can bloom in such hot weather, but several flowers bloom throughout the summer months. These blooms provide a bright pop of much-needed color during the heat.

(Click on the link for each flower’s “How to Grow” blog post.)

Possible blooms this month include amaranth, angelonia, basil, celosia, coreopsis, cosmos, four-o-clock, echinacea, gazania, gomphrena, lisianthus, portulaca, purple hyacinth bean vine, ratibida, rudbeckia, salvia, scabiosa, statice, strawflower, sunflower, tithonia, verbena, vinca, yarrow and zinnia.