Low desert Arizona garden in August
What grows in low desert Arizona gardens in August? I’ll show you. All of these pictures come from my garden in Mesa, Arizona. Gardening during the summer months in Arizona is challenging. In this post, you will learn what to plant, fertilize, harvest, and prune during August to have a successful garden in Arizona.
Low desert includes elevations below 3500 ft in the Southwest, such as the Phoenix and Tucson metro areas.

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What to do in your low desert Arizona garden in August

- Prepare your Arizona garden in August for fall planting by removing spent summer-heat-loving vegetables and vegetables past their prime.
- Prepare the soil and your garden for fall planting by adding fresh compost to the soil.
- Read “How to start a garden in 8 simple steps” to get started on your garden if you are a first-timer or are looking for a few tips.

If monsoon conditions exist, consider a “monsoon planting.” August is an excellent time for a monsoon planting of several summer vegetables to take advantage of the rain and higher humidity of the monsoon season.
Monsoon planting can yield harvests in September and October. To learn more about monsoon gardening, read this post.

Low desert Arizona garden beds in August
- Prepare beds for fall planting. Add compost and other organic matter to the soil.
- It’s important to have your soil tested at least once a year. A soil test can determine the health of your soil.
- Add a balanced fertilizer if needed.
- Plant vegetables according to the planting calendar for your area. These are the planting guides I use.

Cut peppers back to new growth to encourage a new flush of growth and fall crop. Remove debris around plants to discourage pests.

Armenian cucumbers are best when picked young. Read more about how to grow Armenian cucumbers in this blog post.

Cantaloupe grows well during August. Read more about how to grow cantaloupe here.

Sweet potatoes are taking off. I fertilize them once over the summer (in July or August) and give them regular water. I will harvest these in late October or November.

Okra harvests happen daily during August. Learn how to grow okra in this blog post.

Monsoon planting of tepary beans is growing well.

Malabar spinach is producing well and will continue until we get a frost. Consider leaving a spot for it in your fall garden if you have room.

It’s a great time to plant beans in your Arizona garden in August and get a fall harvest of your favorite types.

Low desert Arizona flowers in August

Keep flowers deadheaded to encourage more blooms. Plan your wildflower garden for fall.

Gaillardia is a perennial wildflower that can grow nearly year-round in Arizona.
Learn more about how to grow gaillardia in this blog post.

Zinnias are heat-loving flowers that grow well during August. Cut faded blooms to encourage more flowers. Read this article to learn how to grow zinnias.

Four o’clock thrives during the summer months in Arizona. Read this post to learn how to grow four o’clocks.



Flowers to Plant Outside & Seeds to Start Indoors Each Month in the Low Desert of Arizona.
• PLANTING GUIDE: Each month lists annual flowers and bulbs to plant outside & seeds to start indoors.
• BLOOMING GUIDE: Photos show what may be in bloom that month.

Arizona Annual Flower Planting Guide helps you learn when to plant flowers in Arizona, and whether to plant seeds or transplants.

Low desert Arizona fruit trees in August

Keep fruit picked on fruit trees. Clean up rotten or fallen fruit to help prevent leaf-footed bugs. Don’t prune this month. Fertilize citrus this month or at the beginning of September.
Lemons and key limes begin to ripen. Harvest as needed. They will continue to ripen over the next several months. The flavor is best right after picking. Lemons can be stored in the fridge for a couple of weeks, but it’s best to leave lemons on the tree until needed. Read this article for citrus growing tips.


Watch pomegranate trees for leaf-footed bugs. Remove by hand and discard severely damaged fruit. Clean up dropped fruit. This article has more ideas for organic pest control.


Low desert Arizona herbs in August
Perennial herbs may look a little spent. Continue to harvest as needed but wait until September to give them a good trim and decide if you want to replant.

Harvest and use basil. Cutting back basil often encourages new growth and keeps it from flowering and going to seed. This article shares how to grow basil.

Fennel is flowering and going to seed. The bees and other pollinators love it.

Arizona Herb Planting Guide helps you learn when to plant over 30 different herbs in Arizona and whether to plant seeds or transplants.
Low desert Arizona garden in August “to do” list

- Purchase garlic this month if you haven’t already. If growing hardneck garlic, store it in the fridge until it is time to plant in October. You can also store soft neck varieties in the fridge until it is time to plant.
- If you want to plant potatoes next month, purchase organic potatoes and let them sprout in your cupboard.
- Refresh containers with additional raised bed mix. Organic matter decomposes and needs to be replenished. I love this soil mix for raised beds and containers.
- Remove spent artichoke heads to save the seeds.
- Harvest any remaining I’itoi onions.
- Save sunflower seeds.
- Deadhead annual flowers (cut off spent blooms).
- Apply the last round of citrus fertilizer to citrus between August and September. Water well the day before you fertilize and again after fertilizing. August is the time for the third application of citrus fertilizer. Fertilize citrus on or around Valentine’s Day, Memorial Day, and Labor Day each year.

- Evaluate plants around the yard. If they are overly stressed, check watering and shade/sun conditions. Consider moving or replanting in another spot later in the fall to improve conditions.
- Contain the urge to plant landscape plants if possible; planting in September is a much better time to plant landscape plants.
- Continue to mulch plants.
- Cut back perennials by ⅓ to clean up and encourage new growth.
- Water plants twice as deep as normal once this month to leach salts from soil around plants roots.
- Plan your wildflower garden for fall.
- Spray off plants with water about once a week to control spider mites
What to plant in the low desert of Arizona in August

Before planting:
- Prepare beds for planting (this post tells you how). Add compost, worm castings, and other organic matter to the soil.
- It’s important to have your soil tested at least once a year. A soil test can determine the health of your soil. I use this test kit from Amazon.
- Add a balanced fertilizer if needed.
Vegetables, herbs & fruit to plant in the low desert in August

(Click the link to read “How to Grow” articles on my website.)
- Amaranth (S)
- Basil (ST)
- Bean (Lima) (S)
- Bean (Bush & Pole) (S)
- Bean (Tepary) (S)
- Black-eyed-peas (S)
- Corn (S)
- Eggplant (T)
- Ground Cherry (T)
- I’itoi Onion (bulb)
- Pepper (T)
- Pumpkin (ST)
- Shallot (bulb)
- Sorghum (ST)
- Sunflower (S)
- Tomatillo (T)
- Tomato (T)
- Winter Squash (ST)
After August 15
- Cucamelon (T)
- Cucumber (ST)
- Summer Squash (ST)
SEED, TRANSPLANT, OR BOTH? S = Seed / T= Transplant

In this article, learn more about using cover crops during summer to improve garden soil.
Vegetable, herb & fruit seeds to start indoors in August

(Click the link for seed sources.)

- PLANTING GUIDE: Each month lists vegetables, fruit & herbs to plant outside & seeds to start indoors.
- HARVEST GUIDE: Photos show what may be ready to harvest that month.
- Planting dates are for the low desert of Arizona (zone 9b).
Flowers to plant in the low desert in August

- Purslane (ST)
SEED, TRANSPLANT, OR BOTH? S = Seed / T= Transplant
Flower seeds to start indoors in the low desert in August

(Click the link for seed sources.)
- Ageratum
- Alyssum
- Aster
- Baby’s Breath
- Calendula
- Carnation
- Clarkia
- Coreopsis
- Dianthus
- Echinacea
- Evening Primrose (can be invasive)
- Foxglove *look for first-year blooming varieties like Dalmation and Camelot
- Gaillardia
- Hollyhock
- Lobelia

When you are ready to plant outside, follow the steps in this blog post to harden off seedlings correctly.

Arizona Vegetable Planting Guide helps you learn when to plant vegetables in Arizona and whether to plant seeds or transplants.
With more than 50 vegetables listed that grow well in the low desert of Arizona, you are sure to find one to try.

Want more information about gardening in Arizona? This blog post shares 7 tips for how to grow a vegetable garden in Arizona.
Seed Box Labels with planting dates for vegetables and flowers



If this post about how to grow a garden in Arizona during August was helpful, please share it:



Bob
Tuesday 15th of August 2023
What about flowering tobacco (nicotiana)?
Angela Judd
Tuesday 22nd of August 2023
I'm not sure.
Kit Anderson
Thursday 25th of August 2022
Do you grow watermelon? Have some beautiful plants but all fruit split. Been hearing the same from quite a few AZ growers. Maybe a video on that?
Angela Judd
Friday 26th of August 2022
Splitting is a water issue. We've had a wet summer, that could be why.
Donna
Wednesday 10th of August 2022
Where are the little flower and herb pop-ups that show what you can this month?
Angela Judd
Wednesday 10th of August 2022
There are not good flower and herb planting options for August. There will be more beginning in September.
Kim
Monday 18th of July 2022
Hello, of the listed veggies do you direct sow or grow indoors and transplant? Thanks
Angela Judd
Tuesday 19th of July 2022
If it says plant seeds that means direct sow. Plant transplants means you are planting from seeds started indoors previously or from purchased transplants. Hope that helps.
Donna
Thursday 5th of August 2021
Are you no longer showing the "What to plant now" for herbs and flowers? I can never find the link to them so I'm wondering.
Angela Judd
Thursday 5th of August 2021
For most other months they are listed, but I don't recommend planting most flowers and herbs in August. The warm season ones are already planted and it's a bit too warm for the cool season ones. If you wait just a bit most herbs and flowers will be more successful.