Low Desert Arizona garden in September

What grows in low desert Arizona gardens in September? I’ll show you. All of these pictures come from my garden in Mesa, Arizona. 

We garden year-round in many parts of Arizona, but we can’t grow everything all year. Take a look at what’s growing this month, and let me know in the comments what’s growing in your garden. 

Arizona Garden in September

September! We’ve almost made it through the long hot summer. The good news – lots to plant this month in the garden. The bad news – the days are still hot. Even so, the mornings and evenings are beginning to cool off, reminding us why we love to live in Arizona!

Gardening in Arizona means there is something to plant or harvest year round. Most vegetables can be grown in Arizona if they are planted at the right time, and for a lot of vegetables, September is the right time. Prepare your Arizona garden in September for fall planting by amending with compost and organic fertilizer.

Disclaimer: this post contains affiliate links. See my disclosure policy for more information.

Pests in the low desert Arizona garden in September

Unfortunately, the slightly cooler temperatures of September are inviting to pests. It is important to make efforts to prevent pests organically, but not all pests can be prevented. Be on the lookout this month for infestations in the garden. 

Spider mites are a type of arachnid. Relatives of spiders and ticks, they can suck the life out of plants (literally). Prune out large infestations, and spray off with water or neem oil. You may need to treat repeatedly.  Spray plants off with water regularly to prevent future infestations.

Arizona Garden in September #gardening #garden #arizonagarden

Tecoma plants, yellow bells and bougainvillea often get infested with small caterpillars at this time of year. If the plant is large, it usually survives the infestation without affecting the overall health of the tree. If you decide to treat, here are a few choices: spray off with water, soapy water, neem oil or use BT. When the weather cools a bit, the caterpillars will have moved on. Prune severely infected branches. 

Arizona Garden in September #gardening #garden #arizonagarden

Whiteflies are active in the warm weather of late summer and early fall. Aphids are most active in cooler weather. If you notice infestations of either, try a soapy water treatment, giving particular attention to the undersides of leaves. Spray in the morning and be sure to rinse plants off afterwards. Several treatments are usually necessary. 

What to Grow and Plant Arizona Garden #arizonagarden #arizona #garden #garden

What's growing in the low desert Arizona garden in September?

Arizona Garden in September #gardening #garden #arizonagarden

Peppers are picking back up again. If you did not give them a light prune in August, go ahead and do it in September. Mulch plants with compost and water deeply. 

Arizona Garden in September #gardening #garden #arizonagarden

September harvest picture: Edamame is finishing up, lots of snake beans, a couple monsoon-planted squash or cucumbers, and some kale

Arizona Garden in September #gardening #garden #arizonagarden

September is a good time to plant cole crops (Brassica oleracea). These include plants such as kale, Brussels sprouts (pictured here), broccoli, cabbage and cauliflower

What to Grow and Plant Arizona Garden #arizonagarden #arizona #garden #garden

Which flowers are growing in the low desert Arizona garden in September?

September is a time of change in the annual flower bed. Clear out summer blooming annuals and amend beds well with compost. Once daytime temps are below 100, begin planting cool-season annuals from seed and transplants. Consider planting snapdragons, alyssum, lobelia, pansies, geraniums, calendula, nasturtium, bachelors buttons and stock. Water newly-planted annuals each day until they show new growth and are established. 

Arizona Garden in September #gardening #garden #arizonagarden

Blue Daze is an evergreen member of the morning glory family with blue flowers. This low maintenance plant thrives in tree wells or containers.  

Arizona Garden in September #gardening #garden #arizonagarden

Blackfoot daisy loves hot dry conditions and does well in rocky areas. This low-mounding perennial gets about 2 feet wide and 1 foot high. 

What to Grow and Plant Arizona Garden #arizonagarden #arizona #garden #garden

What's happening with fruit trees in the low desert Arizona garden in September?

Arizona Garden in September #gardening #garden #arizonagarden

Lemons are beginning to ripen in September. Skin color is not always an indicator of ripeness, so taste fruit to see when it is ready. Fruit stores best on the tree. The longer the fruit stays on the tree, the sweeter the fruit becomes. Fruit will not ripen once picked. Ripe citrus fruit can be left on the tree for up to 6 months depending on the variety.

Pomegranates will be ready to harvest in October. Remove fallen and infested fruit to keep leaf-footed bugs under control. Want to learn more about growing pomegranates? This article will help

What to Grow and Plant Arizona Garden #arizonagarden #arizona #garden #garden

What's happening with herbs in the low desert Arizona garden in September?

Basil is going strong. Continue to harvest to keep the basil from going to seed. Try one of my favorite ways to use fresh basil in this recipe. This article shares how to grow basil

The oregano, mint and other perennial herbs are looking a little haggard. Once temperatures dip below 100, trim them back by about 1/3 and feed with organic fertilizer and water well. The herbs should bounce back and look good again soon. 

Arizona Garden in September

Arizona low desert garden in September to-do list:

  • Prune summer-damaged perennial herbs back by about 1/3.
  • Fertilize herb and vegetable beds, add compost as well. 
  • Do not prune fruit trees this month. 
  • Fertilize citrus trees, if you didn’t do it in late August. Water citrus deeply this month, before and after fertilizing. 
  • Once temperatures are below 100, begin to adjust time between watering citrus and other fruit trees to around twice a month. Water deeply but not as often as in the summer months
  • Clear out summer-blooming annuals and make room for cool-season flowers and annuals. Save seeds from zinnias
What to plant in September in Arizona

What to plant in the low desert Arizona garden in September:

Arizona Vegetable Planting Guide helps you learn when to plant vegetables in Arizona, and whether to plant seeds or transplants.

With 50 vegetables listed that grow well in the low desert of Arizona you are sure to find one to try. 

Arizona annual flowers planting guide helps you learn when to plant flowers in Arizona, and whether to plant seeds or transplants.

Arizona Herb Planting Guide helps you learn when to plant over 30 different herbs in Arizona, and whether to plant seeds or transplants.


Arizona Garden in September
Arizona Garden in September #gardening #garden #arizonagarden

Want more information about gardening in Arizona? This blog post shares 7 tips for  how to grow a vegetable garden in Arizona


5 comments on “Arizona Garden in September”

  1. Love this, thank you! I’ve bookmarked this page to read later tonight. We just bought a new house with lemons, limes and pomegranates and they’re all in rough condition. The trees look great, but the pomegranates split, and the lemons and limes are small and green. I’m also beginning to plant a few things in containers (cabbage, herbs, etc.). Can’t wait to read through this and get some tips!! 🙂

    • Congratulations on your new home. That’s great about the trees. Once you begin watering and fertilizing them properly the fruit will respond and you will have great harvests if not this year, certainly in future years. I’m so glad it is helpful!

  2. Love your blog. We live in Las Cruces NM and I feel I can truly follow your gardening advice here. Unfortunately we are in a rental for now that is a yard full of rocks! I tried planting in barrels but it just got too hot over the summer. I do have a Celebrity tomato plant that is perking back up and even has some tomatoes on it. We are building a home and hope to be in it by January. Can’t wait to get gardening again.

    • Glad to hear about your tomato. None of mine made it through the summer. Best of luck in your new home, congratulations and happy gardening!

  3. This was such a hot summer! None of my tomatoes survived either. I have fingers crossed and hoping cooler weather gardening may be more successful for me this year! How exciting about your new build, congratulations!! I’m newly moved to Tucson, and learning how to garden in this weather. Loving it so far!

Leave a Reply

Your email address will not be published. Required fields are marked *