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Arizona Garden in September

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. 

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.

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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. Read this article for organic pest control that really works

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

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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. 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. 

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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

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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. Learn how to grow oregano in this post

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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
  • Find seed potatoes and begin the process of “chitting” them, so they will be ready to plant late this month or October. Learn more about how to grow potatoes in this article
  • Order garlic so you are ready to plant it in October. Store it in the fridge until it’s time to plant. 
  • Begin fertilizing roses again this month. Keep up with watering every few days until temperatures cool in October. Once temperatures are below 100℉, prune roses lightly to remove dead or diseased canes.
  • Plant spring-flowering perennials this month.
Arizona Garden in September

Vegetables 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. 

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

Arizona Garden in September
  • All month long plant: Begonia, Dianthus, Foxglove, Forget-me-not, Bells of Ireland, Baby’s Breath, Geranium, Marigold
  • After September 15th plant: Calendula, Candytuft, Cornflower, Delphinium, Gaillardia, Larkspur, Snapdragon, African Daisy, Clarkia, Verbena, Salvia, Lanaria, Lobelia, Gazania, Petunia, Flax

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

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

Would you like the low-desert planting dates for vegetables, herbs, and flowers in a convenient calendar? 

*PLANTING GUIDE: Each month has a planting guide (letter boards) for the vegetables, herbs, and flowers to plant in the low desert of Arizona. 

*HARVEST GUIDE: Harvest guides are the harvest photos of what it is possible to harvest each month. 

Arizona Garden in September
Arizona Garden in September


Sunday 19th of September 2021

I just moved here from Alaska and have been watching your videos and reading your blog to learn about gardening here. Where do you usually buy your seeds from? In particular, seed potatoes?

Angela Judd

Sunday 19th of September 2021

Welcome to Arizona! Seed potatoes are tricky because they are often not available when it is time for us to plant. I often sprout ones I purchace from Sprouts or another grocery store. My favorite seeds are from Botanical Interests. You can find them at local nurseries or online. If you purchase them through this link: I receive a small commission.


Wednesday 1st of September 2021

I am so trying to learn to garden here in Tucson. We moved from Missouri where I had to hide veggies in the neighbors mail boxes I grew so much. I straw bale gardened there. However, I have not been able to grow a bloody thing here with the exception of 1 banana pepper that I finally threw in the backyard to "die". It lived so I figured if it was that much of a fighter I'd fertilize it and give it some water. Gardening here has been abysmal at best....I planted according to your August schedule in new raised bed garden plots with good organic soil and most all of it never even came up. Broccoli, Kohlrabi, celery, cabbage, beets, carrots...nada, zip. I fully realize there is "no crying in gardening" but I'm about at the end of my hoe with trying here! I will give it another whirl this month and see if anything comes up....after that, I think I'll just throw in my hoe.....

Angela Judd

Friday 3rd of September 2021

Sorry to hear that. Sounds like you are on the right track. Fall gardening can be much more rewarding than gardening when it is so hot. I hope things improve for you soon. May the gardening odds be ever in your favor.

Jennifer Lewis

Friday 27th of September 2019

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!

Kathy Tarazoff

Thursday 26th of September 2019

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.

Angela Judd

Thursday 26th of September 2019

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!

Jennifer Lewis

Wednesday 25th of September 2019

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!! :)

Angela Judd

Wednesday 25th of September 2019

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!