Tips for Starting a Vegetable Garden in the Desert

Many of the urban homesteading books you can pick up at your local shop will tell you how easy it is to plant some veggies in containers and eat fresh food right from your patio or backyard. While this may be true for the seasoned author writing about all these things, in reality it's hard to start growing all your own food, especially in the desert. Since my garden is at a standstill due to the soaring temperatures, I thought I would take some time to give you some tips about growing veggies in the desert.

First off learn your hardiness zone. The hardiness zones were determined by the USDA to help farmers know what will grow successfully in their area. "The map is based on the average annual minimum winter temperature, divided into 10-degree F zones." USDA Here in Tucson we are in zone 9b. Our average minimum temperature is 25-30 degrees.  We have very few frost days which allows for a lot of fall and winter growing. 


Next look at the space you have and determine if you have ample shade. The desert in the height of summer is really brutal to plants, even the sun loving kind like squash and melons. Imagine two weeks with no clouds, 110 degrees with 10-15 mph winds and 5% humidity. People like to joke it's a dry heat but that is an understatement. Shade is really really important. If you can, plant on the east side of your house so that the garden is in sun in the morning to midday and then shaded in the afternoon so the plants can cool off. If you can't plant on the east side of your house, plant near a tree that will cast a shadow in the afternoon or install 50% shade tarps over your beds before planting. 


Soil testing. If you have the space in your back yard and you want to plant in the ground do a soil test first to see what nutrient amendments you need to do. What do I mean by amendments? Nuritents like nitrogen, phosphorus, magnesium and so on.  Plants like nitrogen in their soil; it makes for dark healthy leaves.   The soil here is very salty. It is also very hard and compact. You'll need to do a whole season's worth of amending before planting. Lots and lots of compost rich in organic matter that will make the soil light yet retain water. You can get a simple soil test kit at your garden center or send a sample to a professional lab. If you decide to put in raised beds and will be adding bought soil to it a test kit will be sufficient.

Put in raised beds. Honestly it's much easier as a first time gardener to put in raised beds then to rent equipment to help you dig up the soil. Raised beds are great as they help keep the soil cooler and you can regulate water retention better. You are less likely to have to deal with the zombie apocalypse of snarling, mean, thorn-covered weeds that are blown in on the wind here. Cover your raised beds with shade cloth if they are not in a place with afternoon shade.

Run a drip system to the beds. Having a drip system here is a time and water saver. Water deeply twice a week during the hottest periods of June-August. This means leaving the system on for 2 hours at a time. Allowing the soil to get really soaked. You want the water to go down to the bottom of your beds so that the roots grow downwards. This makes for more heat resistant plants.  If you only water for a few minutes say 30 every other day, your plants roots with grow close to the surface where the water is and they will need water all the time.

 *note how the plants in the sun are wilting but those in the shade are fine. 

Water when you see wilting. If you see your plants wilting during the middle of the day, don't hesitate to give them a drink. This will help keep off stress. If your plants are still wilting after you've watered them and the heat of the day is gone then you probably have other issues you'll want to look, like mold, disease or insects. If your plants are stressed they won't produce much or at all; I've had giant vines that lived a whole season but did not make one pod.

Mulch. It took me four years to suck it up and go to the feed and tac shop to buy a bail of straw to put down as mulch. I'm really happy I did it though because my plants are much happier and I have way less weeds.  Simply put down 3-4 inches of straw around your plants to give the roots cool soil. In the heat of the desert, cool soil is really important to reduce stress on the plants.

Planting seasons. The low desert has two planting seasons. February- May and September-November.  These date ranges are when the temperatures are most pleasant for the plants. Warm days and cool nights without many extremes. You can certainly grow veggies from June-August but know it will be very stressful on the plants with the high temperatures and you may not get very much produce.

Pick sun-loving seeds. You want to make sure to pick seeds that are well adapted to hot temperatures. Try looking to native seeds such as those from the Native Seed Search.  Seeds that do well with little water and lots of heat and sunshine. Think winter squash, peppers, melons, eggplant, sunflowers.

Keep a journal. Keeping a journal of all the successes and disasters will help you learn from year to year. Take pictures and note what they are about. Take pictures when your tomato plants start to turn yellow and dry up for no reason at all... or when suddenly your whole melon plant is covered in ants herding aphids. This way you will have a reference guide to ask a more experienced gardener what to do.

Talk to experienced gardeners. This is the big key to success. When you don't know what to do or have a problem as your local gardening group or your county extension office. They will help you out. I've also had success having the farmers at the farmers market give me suggestions, especially after I buy there for a few months or buy a seedling. Obviously the ones that just buy their produce can't help, but the ones doing local farming have great advice (and the best produce). Talking to someone who's been gardening in your zone for year and years is always heart lifting! Who knows, you may even make a new friend.

Last but not least, don't give up when everything fails! Remember that people have been living off the heart for thousands of years in your region without technology, stores, or running water, and they made it work (I don't think I have readers from the South Pole). There is always another season coming up, so get to sowing new seeds when disaster strikes.