GROWING TOMATOES IN THE DESERT

Page 1 of 2

 

TOMATO GROWING TIPS:

1.                   For best results, select short-season varieties with less than 70 days to maturity. 

2.                   Tomato pollen becomes sterile in the heat--over 90º your tomatoes most likely will not set fruit until heat stays below about 90º F or above 55° F.

3.                   Make sure your soil is enriched with 6”-8” of composted organic material 2 to 3 weeks before planting. After planting, set out an organic layer of mulch 6” to 10” deep above the ground around tomatoes, 2” away from the stem of tomatoes.  Straw, dead leaves or layered shredded newspapers work. This shades the roots to protect your tomatoes from heat and makes a barrier from some pests.

4.                   “Harden off” new plants by gradually exposing them to outdoor weather conditions for a few hours at a time over 3 to 5 days when you bring them home from a nursery or from seedlings you start indoors.

5.                   Set out new plants mid to late February and then again July 15 to early August; trim back old plants by 1/3 or 1/2 for second fruit set in fall.  Plant cold weather varieties in the fall like Stupice, Glacier, Early Wonder, Legend or Siletz. Grow warm weather varieties for summer such as Celebrity, Champion, Black Russian or Brandywine. Set out transplants by “entrenching” them: remove lower leaves below the second node, lay stem horizontal to the soil, over a source of phosphorus (starter solution or bone meal), then cover with at least 2” of soil.  The hairs on the stem will turn into roots and make a stronger plant.

6.                   Small and medium tomatoes do much better in the desert than large-fruited varieties. Cherry and grape varieties are some of the best performers. Sun Gold is one of the most flavorful varieties.

7.                   Fertilize regularly every two weeks to help keep plants strong.  Remove yellow leaves to keep whiteflies away. Make a sticky trap with a yellow plastic jug or yellow cardboard covered with petroleum jelly.

8.                   To prevent disease, do not plant tomatoes or other  Solanaceae family members (peppers, potatoes, petunias or eggplant) in the same soil every year, rotate your crops.

9.                   Don’t stake up plants or prune side shoots.  This allows more leaves to shade and protect blossoms and fruit. Tomatoes need protection from full sun in the summer. Also protect plants from frost by placing a frost cloth (you can use commercial frost cloth, bed sheets, a light blanket but never plastic) a few inches above but not touching the plants.  You can put a string of old-fashioned Christmas lights or outdoor light bulbs to keep them warm (LED lights do not provide enough heat to protect from frost).

10.               Shake flowers or spray with bloom set spray you can buy at plant nurseries if you want to increase yield and hasten fruit set.

11.               Increase watering during early growing period and on the hottest days to help prevent thick skins, cracked and leathery tomatoes. Keep the soil evenly moist like a wrung out sponge to prevent blossom end rot and keep your plant from wilting.  (Too much water can also cause wilting).  Try to water only the soil, do not sprinkle the tomato leaves to minimize the spread of disease and sun scalding.

12.               You can plant on the east side of a wall to get morning sun and afternoon shade.  To protect tomatoes from frost in the fall, use PVC for a framework, drape clear plastic over to create a mini-greenhouse.

13.               You can shade tomatoes in the summer by draping a light cloth over them in the hottest months.  This creates a barrier from leaf hoppers and provides a more humid environment for the tomatoes. Too dense of shade cloth may delay ripening.  You can purchase 30% - 70% shade cloth at nurseries.

14.               Don’t pick too soon. Let them really ripen up as much as you can on the vine.  If birds or bugs are a problem, pick as soon as they show color and finish ripening indoors. For best flavor (like bananas) never refrigerate tomatoes.

 

Good varieties for planting tomatoes in the desert  KEY: (I=indeterminate, D=determinate, H=heirloom)/ Numbers are days to maturity/ Disease resistance: VFN or VFNT.

Cherry/Grapes: Sun Gold (I-55), Gold Nugget (H-60), Sweet 100 (I-65), Black Cherry (

 

Medium-size (6-8 oz.) Early Girl (I-50), Oregon Spring (I-58), Heatwave (D-70), Pearsons, Celebrity (D-70, VFN), Better Boy (I-70, VFN), Champion (I-62 days to maturity, VFNT), Stupice (I, H-70), Cherokee Purple (I, H-80)

 

References:

“Desert Gardening for Beginners--How to Grow Vegetables, Flowers and Herbs in an Arid Climate” by Cathy Cromell, Arizona Master Gardener Press, 1999. Best local garden guide. Includes planting calendars, information on soil preparation, fertilizing your plants, diagnosing diseased plants, integrated pest management and tips for growing tomatoes.


 

GROWING TOMATOES IN THE DESERT

Page 2 of 2

 

Website Reference:  http://ag.arizona.edu/maricopa/garden/

Find garden tips, how to diagnose plant problems, garden clubs, Master Gardener program information, Ask a Question, community gardens, gardening events, recommended reading and much more.

 

TOMATO TERMS

Indeterminate vines keep producing new shoots and blossoms even after the first fruit sets and until killed by frost.  Tomatoes in all stages of development may be on the vine at once and harvest is extended.  Small amounts of tomatoes ripen at one time.  Longer growing time may mean more problems with cracking, sunscald, white flies and possibly less production.  Good for home gardens.

 

Determinate plants tend to set fruit at the same time.  Harvest time is short as all the fruit ripens at about the same time.  Determinate tomatoes are good for canning.  May be less flavorful than Indeterminate and Heirloom.

 

Heirloom varieties of plants are those that were introduced to the public prior to 1940.  They were usually handed down from one generation to another and tend to have amazing flavor.  Some heirlooms have long days to maturity which make the harder to grow in the desert. Try to pick varieties with 70 days or less to maturity. Heirlooms may be less resistant to diseases than some hybrids.

 

RIPENING GREEN TOMATOES

Use one of the two methods below or use green tomatoes to make Fried Green Tomatoes, Chow-Chow or Piccalilli.

 

Shake Up Your Tomato Roots

Rebecca’s Garden, Home and Garden Television, Episode #3003, aired 10/12/98 transcript from www.rebeccasgarden.com.

 

Take a garden fork and push it into the ground about 12 inches from the stem of the tomato plant.  Rock the fork back and forth.  Do this all the way around, being careful not to uproot the plant. 

Now, by disturbing the root system, what we’ve done is stress the plant.  This will actually shut off any more energy that goes to growing larger tomatoes.  So, we’ve shut off the growing process while turning on the ripening process.  This technique works great if you do it a few weeks before your first expected frost.  But if the weather throws you for a loop and frost is in the forecast you want to harvest the tomatoes.

 

Ripening Green Tomatoes off the Vine

Line a shallow container with newspaper, and then very carefully place the blemish-free tomatoes on top.  It’s important not to let the tomatoes touch each other, and do not wrap the tomatoes with newspaper.  This will allow you to keep an eye on them in case of rot.  Now the next step is to store them in a cool, dark location.  Keep an eye on them, because if one of them starts to rot, you need to get rid of it, or it can ruin the rest of the tomatoes.  When they start turning colors, bring them up on your kitchen counter and you will soon enjoy fresh, ripe tomatoes.

 

Information provided by Lee Ann Aronson, Master Gardener Volunteer

University of Arizona Maricopa County Cooperative Extension