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How to Grow Tomatoes in Arizona – 10 Tips for Growing Tomatoes

How to grow tomatoes in Arizona - 10 tips for growing tomatoes #tomatoes #arizonagardening #howtogrowtomatoes

Learning how to grow tomatoes may feel overwhelming. Entire books have been written about growing tomatoes, but these 10 tips will fast-track you to tomato-growing success. 

The taste of homegrown tomatoes is the reason many people begin a garden. In the United States, it is said that more gardeners grow tomatoes than any other vegetable.

Wondering about how to grow tomatoes in Arizona, the low desert and other hot climates? Keep reading, there is plenty of information for you too!


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10 Tips for How to Grow Tomatoes


Tip #1 for Growing Tomatoes: Choose a tomato variety suited for your tastebuds and climate

How to Grow Tomatoes in Arizona - 10 Tips for Growing Tomatoes

Decide which type of tomato you want to eat. Different types of tomatoes are suited for eating fresh, canning, making salsa, or cooking

For the best chance of success, choose a type of tomato suited to your climate as well. Because of the heat of Arizona summers, we have a short growing season. Look for plants with a short (60-90) days to maturity. These are often types with small to medium fruit or Roma or paste varieties. Varieties highly recommended for desert climates like Arizona include Punta Banda, Celebrity, Pearson, and Cherokee Purple. 

Different climates have other considerations and growing conditions. Ask a local grower for varieties that do well in your area.


Tip #2 for How to Grow Tomatoes: Plant tomatoes at the correct time

To give tomato plants the best chance for success, plant tomatoes right after the last spring frost date. For the low desert of Arizona, this is usually around February 15th For this planting start seeds indoors from December 15 – January. 

Once planted, if necessary, protect plants from cold nighttime temperatures. Plant tomatoes in the morning, so tomatoes have the day to settle in before cooler nighttime temperatures. 

There is a second (monsoon) planting window for planting tomatoes in the low desert of Arizona at the end of July through mid August. For this planting start seeds indoors from May 15 – June. 

Once planted protect plants from high daytime temperatures with shade cloth. Plant tomatoes in the evening, so tomatoes have the cooler evening to settle in before hot daytime temperatures. 

Tomatoes grow best in temperatures of 70℉ to 90℉ with nighttime temperatures consistently above 55℉. In Arizona, you want tomatoes to flower and set fruit before it gets too hot. Once temperatures reach 90℉, tomato pollen is not viable. Fruit that has set will continue to mature, but new fruit will not set if pollen is not viable. 


Tip #3 for Growing Tomatoes: Plant tomatoes in the right location

  • The most important requirement for productive tomatoes is plenty of sunshine.
  • Give tomatoes full sun for the entire plant with adequate growing space around each plant for air circulation.
  • Allow 2 feet between each plant for healthy and productive plants.
  • Do not plant tomatoes in the same location year after year. Rotate the location to prevent build-up of disease in soil.  

Tip #4 for How to Grow Tomatoes: Prepare soil correctly

Tomatoes need soil rich in organic matter; make a habit of amending your soil with compost. Good drainage is important as an area with standing or puddling water invites disease. Prepare your soil correctly and your plants will thank you. If you are growing tomatoes in raised beds, this article talks about the best soil for raised beds


Tip #5 for Growing Tomatoes: Plant tomato seedlings deeply

Planting deeply encourages a more extensive root system and a healthier plant.

  • Remove the bottom 2/3 of leaves on the tomato transplant.
  • Dig a shallow trench or deep hole (depending on depth of planting bed) and plant transplant so that only top leaves are above the ground.
  • Roots will grow along the entire stem of the plant.
  • Bear in mind that after planting the tomato, plants may appear to do nothing for a bit- but they are growing roots.

Tip #6 for How to Grow Tomatoes: Mulch tomato plants well

Use compost, straw, leaves, or pine needles to reduce evaporation and insulate the soil from extreme hot and cold temperatures; soil will stay at a more even temperature. 

Mulching helps control weeds, and plants will not have to compete with weeds for water and nutrients. Most mulch ultimately becomes fertilizer as it decomposes into the soil around the plant.

How to Grow Tomatoes: Mulch tomato plants well


Tip #7 for Growing Tomatoes: Water tomato plants correctly

  • Water early in the day to prevent excessive evaporation.
  • It’s best to water at the soil level so leaves do not get wet. Wet leaves encourage disease.
  • Water to a depth of at least 12 inches to encourage roots to grow deep in the soil to find nutrients and moisture. 
  • Water slowly and deeply.
  • Deep, extensive roots help plants withstand dry spells.
  • Water regularly as needed, but do not allow plants to become soggy as plant roots need oxygen.

Tip #8 for How to Grow Tomatoes: Feed tomato plants

When planting, if your soil is low in phosphorus it’s important to provide a source of phosphorus (bone meal or rock phosphorus) and again as plants begin to bloom and produce fruit. A soil test can determine if your soil is low is phosphorus. Without proper fertilization, plants do not produce well and are prone to weeds (which invite pests and other diseases).

Once tomatoes set fruit feed them every two-three weeks. Tomatoes do best with regular feeding from organic sources of fertilizer

How to Grow Tomatoes: Feed tomato plants

Tip #9 for Growing Tomatoes: Provide support for growing tomato plants

It’s important to encourage tomatoes to grow vertically.

Growing Tomatoes: Provide support for growing tomato plants
  • Growing tomatoes vertically keeps the plant upright, and prevents the stems from breaking from heavy fruit or wind.
  • Trellising tomatoes also keeps the leaves off the ground which helps reduce diseases.
  • Fruit is easier to harvest when it is off the ground as well. 
Growing Tomatoes: Provide support for growing tomato plants

Tip #10 for Growing Tomatoes: Provide shade for tomato plants in extreme climates like Arizona

Provide shade for tomato plants in extreme climates like Arizona
Provide shade for tomatoes in extreme heat

Your plants may need a little help to get through a long, hot summer in the low desert of Arizona.

  •  Shade can reduce the air temperature for tomatoes by several degrees, and it also extends the growing season.
  • Providing shade in desert climates helps reduce stress on tomato plants, and can prevent sunscald on ripening tomatoes.
  • Shaded tomato plants are more likely to survive the extreme heat of the desert, and may perform better when cooler temperatures return in the fall.
Provide shade for tomato plants in extreme climates like Arizona
Sunscald on tomatoes

How to grow a vegetable garden in Arizona #arizonagardening #arizonagarden #desertgardening #hotweathergarden #howtogarden

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


If you found this post about how to grow tomatoes in Arizona helpful, please share it:


Leslie

Friday 6th of May 2022

Thank you Angela for sharing all your wisdom. I have learned so much from your website and videos! It is very difficult to find gardening advice that pertains to Arizona gardening so you are a rare gem. Would you consider writing more specifics about the second “monsoon” planting of tomatoes. Specifically, how to you harden off seedlings in such hot weather and should you use shade cloth beginning at planting? Thank you!

m

Wednesday 20th of April 2022

Do you recommend growth bag for tomatoes in Chandler? how many gallon growth bag? Thanks.

Angela Judd

Thursday 21st of April 2022

Yes. At least 10 gallons of soil. Here is a blogpost that may be helpful: https://growinginthegarden.com/gardening-in-grow-bags-5-tips-for-success/

Mae

Tuesday 22nd of February 2022

Hi Angela! Would an organic fertilizer with an NPK of 5-7-3 provide enough phosphorus when planting tomato transplants in a raised bed?

Mae

Saturday 26th of February 2022

@Angela Judd, ok thank you!!

Angela Judd

Friday 25th of February 2022

Hi Mae, I would consider having your soil tested before adding more phosphorus. This is the soil test kit I use: https://amzn.to/3C0R0ST

geoff teichmann

Monday 13th of December 2021

I have a Celebrity plant that is showing some curly leaves. The leaves are still nice and green. Nearby I also have an Early Girl plant that looks fine. Are these curly leaves anything to be worried about ? Both plants have lots of tomatoes on them. What causes the leaves to curl this time of year ?

Thanks for your help !!!!

Terri

Friday 3rd of December 2021

Hi Angela. I have a question about tomatoes. I have two really large, healthy San Marzano plants that are covered in tomatoes however they’re not ripening. I picked some and tried to ripen on a window sill with no luck, they’re still green. Any tips? Are the days getting too short for them to ripen on the vine at this point? Also, do you have luck keeping your tomatoes throughout the winter by covering at night or do you start over in the early spring? Mine are so pretty and healthy I’m hoping they’ll survive the winter and I’ll get a jump on a nice spring harvest. Thank you for all of the great videos and tips.

Angela Judd

Monday 6th of December 2021

Just posted a video to my YouTube and Instagram about this topic. Check it out for ripening tips. I tend to replant each season, but if we have a very mild winter (which it looks like it might be) then I will keep my tomatoes going through spring.