GROW TOMATOES in the HEAT- Best VARIETIES, Soil and Planting Tips

If you've ever thought, maybe tomatoes just don't grow in the low desert, think again and watch this video before you give up. Today I'm sharing 10 tips for growing tomatoes in extreme heat. We'll talk about the best varieties and how to keep plants alive through summer. We'll walk through the whole year so you know what to expect and what to do. I'm Angela from Growing in the Garden in Mesa, Arizona. For more desert gardening tips, like, subscribe and stick around. Tomatoes like warm temperatures but only set fruit when daytime temperatures are in the 70s and 80s and nights are in the 50s and 60s. Once days are consistently in the 90s and above and nights stay warm, pollen becomes sticky and less viable. Blossoms dry up and fall off without setting fruit. That's why in the low desert we see great fruit set in the spring, almost nothing in July and August and then another flush in the fall when nights cool down again. Heat also affects ripening. The red pigment in tomatoes develops best with temperatures in the 70s. When fruit gets very hot, they struggle to turn red and can develop yellow shoulders or ripen unevenly. So our strategy is simple. Encourage as much flowering and fruiting as possible in the spring and fall and try to keep them alive over summer. Variety choice makes a huge difference in extreme heat. First, fruit size. Big beef steaks are delicious but with short seasons you don't always get a consistent harvest. Smaller fruited types like cherry, grape and plum or paste tomatoes are more reliable producers. They set earlier, handle the heat better and keep producing when larger types slow down. Second, look at the days to harvest number on the seed packet and choose tomatoes that mature in about 70 days from transplant. The sooner they set fruit, the more of that fruit will develop before it gets hot. Third, look for heat set or hot set types like jolene. Many hybrids are bred to set fruit when it's warmer than ideal. And finally, look for disease and nematode resistance. In warm soils, root knot nematodes and soil diseases can be a real issue. The top choices for me? Celebrity, Cherokee Purple, Early Girl, Black Crim and Punta Banda. Cherry or grape types? Sun Gold, Juliet, Sweet 100 and Yellow Pear. In the low desert, timing is almost everything. We have to maximize production with our short seasons. I think of tomatoes here in four phases. A spring planting and growing window. A summer survival mode. A fall planting and growing window. And winter survival for a head start. Here's what a year of tomatoes looks like in my low desert garden. I start seeds indoors in December or January, so transplants are ready to go in the garden in mid-February or March. Once that frost danger is passed and the soil is at least 60 degrees. Those plants set most of their fruit before the worst heat. In June, I'm busy harvesting, but already looking ahead to fall and monsoon planting. Starting more seeds indoors and trying to keep the existing tomatoes alive through the summer. In August and September, I'm planting new transplants and pruning and fertilizing the healthy spring plants that survive the summer to encourage a new flush of blooms. I want all the plants to set most of their fruit before it gets too cold. As temperatures cool down in late fall, I harvest what I can and bring some fruit indoors to ripen. During frost events, I cover plants so they make it through any freezes. Those survivors already have an established root system. And as soon as days warm up, they often give me my earliest spring tomatoes. Where you plant matters as much as what you plant. Tomatoes need plenty of sunlight, but they don't want to bake against a west-facing wall or in a rock island. Look for spots with morning sun and some afternoon shade. Add white 50% shade cloth once temperatures are consistently above 90 degrees. It helps protect blossoms and fruit from sun scald and can extend the season just a little bit. When highs drop back below 90 degrees, take that shade down. Tomatoes like deep, well-drained soil with plenty of organic matter. Our native soil is often alkaline and low in organic matter. So I usually grow tomatoes in raised beds or large containers with a rich soil mix. I use the raised bed and container mix from Arizona Worm Farm and sometimes add a balanced organic fertilizer if the bed is newer. When I'm choosing transplants, I look for short, sturdy plants with dark green leaves and white non-circling roots. I skip leggy or root-bound ones. Tomatoes are happy to be planted deep, so I remove the lower leaves and bury the stem so only the top leaves are showing. That buried stem will root and give the plant a deeper root system. Add supports as soon as possible. Tomatoes need support. I use sturdy cages or trellises so the plants can grow up and the fruit stays off the ground. For determinate tomatoes like Jolene and Roma, I like the tall tomato cages from Garden in Minutes. These tomatoes are more compact and a good cage is usually enough to hold the plant and keep fruit off the soil. For larger, more vigorous varieties, I give them more room. A single Juliet tomato can take up an entire four-foot-wide trellis in my garden. Celebrity is a vigorous determinate that also likes plenty of space and support. For these types, a standalone tomato cage usually isn't enough. There are lots of ways to trellis tomatoes. Whatever you choose, put supports in place at the time of planting if possible. That way, you're not trying to wrestle a big plant into a cage later and damaging roots and branches. Tomatoes need deep, even moisture. Irregular watering stresses plants and leads to blossom end rot and cracking. In my garden, I water at soil level with a drip system. I run the water long enough to soak to a depth of 12 to 18 inches and then I let the top inch or so dry out before watering again. In raised beds during hot weather, that might mean watering every one to three days. But always check your soil first. A thick layer of mulch helps conserve that moisture. For fertilizing, avoid heavy nitrogen. Too much nitrogen means lots of foliage and fewer flowers. Because we have long seasons and frequent irrigation, slow and steady feeding is usually a better choice than big doses. When tomatoes are actively growing, I amend with worm castings and use an organic liquid fertilizer formulated for fruiting about once a month or as needed, especially in containers where nutrients wash out more quickly. In the hottest part of summer, I don't feed tomatoes. They're already stressed and I don't want to encourage new growth. In cooler, more humid climates, people often prune tomatoes heavily to open them up. In the low desert, I'm much more conservative. Every leaf is shade for the fruit. A good canopy protects the tomatoes from sun scald and keeps fruit a little cooler. So I remove leaves that are touching the soil, take off dead or clearly diseased branches, do light shaping and remove suckers if plants get out of control. But I don't strip all of the side shoots or expose fruit clusters in the middle of summer. Think of the leaves as a living umbrella over your tomatoes. In our heat, you want that umbrella in place. Because we're gardening outside of ideal temperatures, here are some of the problems you might see. Dropped blossoms. If flowers are falling without setting fruit during very hot weather, that's almost always temperature, not poor pollination. Focus on shade and deep, even watering and wait for cooler nights. Sun scald. Pale, leathery patches on fruit that later turn brown are sun scald. It usually happens when the fruit is too exposed. Leave more leaves around the fruit and adjust shade if needed. Leaf curl. If leaves are curling but still firm and green, the plant may just be stressed and trying to reduce water loss. If it perks back up in the evening and morning, it's usually just heat stress, not a serious issue. Blossom end rot. Dark, sunken spots on the bottom end of fruit are often caused by uneven moisture and issues with calcium uptake. Mulch and consistent watering help. Cracking. Heavy watering or rain after a dry spell can cause fruit to crack. Some varieties are more prone to it. Again, consistent moisture and picking a little bit earlier helps. If a plant is completely wilted in the cool of morning and never perks up, or you pull it and the roots are covered in swolly knobby galls, or new growth is wilted, twisted, or stunted, that's usually more than just heat stress. It often means root knot nematodes or disease. At that point, I remove the plant. Heat tips won't fix those problems. In extreme heat, it's tough for tomatoes to turn red and ripen. Once fruit has reached full size, I pick it at the first blush of color. That's called the breaker stage, and it will finish ripening indoors. During the hottest months of the year, don't expect big harvests. Keep plants alive with shade and deep watering. When temperatures start to drop, give them a light prune and feeding, or plant new tomatoes. Instead of one long growing season, we get two shorter seasons with a hot break in the middle, and so we do the best we can. If growing tomatoes has been difficult or disappointing, I hope these tips help. For all of my tomato growing resources, head to growinginthegarden.com. Want a thriving desert garden? Join my monthly online classes, live or on replay, and get instant access to past classes and journals. Bring your questions and let's grow together in Growing in the Garden Academy.