Those of us who really love Arizona want to say, “We live here because of the summer not despite the summer.” But to be honest, we all—people, plants, and animals—welcome fall weather. Gardening becomes much more pleasant and the cool season delivers fewer challenges to growing food in our arid climate.
Warm Season Spillover
Many crops bounce back in the fall. Also, you may have planned for a fall crop of tomatoes, peppers, cucumbers, eggplant and other warm season crops and have young plants ready to do their thing in the fall as they did in the spring. If you have some leftover plants that are just too beat up from summer, pull them out. If you are just sick of squash and cannot give any more away, yank out and compost those plants. Make space for the new season’s flavors.
The Space-Efficient Cool Season
While summer crops tend to sprawl, vine and spill, many cool-season crops are predictable, efficient users of space. In fact, cool-season crops produce much more food per square inch of plant. Sometimes summer can make you feel like a terrible gardener due to the challenges the heat poses to edible crops. In contrast, cool season gardening builds confidence because it is relatively easy and takes a lot less resources (especially water).
Preparing the Soil
When you plant cool-season crops, remember that root crops, some herbs, and legumes don’t want soil that is too rich, and it should be well-draining. Most other crops like a good helping of manure, compost and organic fertilizer. If your goal is to be an organic gardener, stay away from synthetic fertilizers. They kill the organisms that feed your plants.
Most cool season crops can be directly sown into the ground and thinned as they come along (you can eat the young seedlings as “microgreens”). Eventually you want to give each plant the space to develop into its mature size. You can cut the tops off some varieties of greens (leaving the base) and they will grow back. Check seed catalog descriptions for varieties that can be handled this way.
You can start the lettuces, cabbages, and cole crops (brassicas such as broccoli) in trays and small pots or purchase them from the nursery, already started. Root crops, legumes, and annual herbs are best directly sown into the ground—they tend to bolt (go to flower prematurely) when started in a tray or pot. Don’t plant legumes next to root crops; legumes have a relationship with soil organisms that produce nitrogen in the soil, and this will make root crops grow very leafy, but not produce great roots.
Also, don’t let the tough summer sun make you think your winter garden needs just as much shade. Over-shaded plants are more prone to pests and other problems and the sun in winter is not so brutal as the summer.
Mulching & Feeding
Once you have thinned your seedlings, mulch thickly with straw. Shading the ground from the sun helps to prevent bolting and saves water. Apply finished compost between rows (under the straw) when needed. This top dressing of compost will help feed plants. If plants are slow to develop you may need to apply some organic fertilizer. Remember good garden soil takes care and time to build.
Yes, sometimes in October we get an early frost, especially at the higher elevations of Baja Arizona. Cabbages, kale, and Brussels sprouts love frost and actually develop good flavor from the cold snaps. Most other crops can survive the frost but benefit from a cover on the coldest evenings. Protect strawberries, peas, artichokes, cardoon, and burdock from all cold snaps. When covering plants, cloth works better than most other fabrics because it insulates. If you use plastic, make sure it is not touching the plants and remember to take it off during the day where temperatures in our region can warm up and bake the plants under that covering.
THE GREENS AND BRASSICAS
There are endless greens to choose from in the cool season: lettuces, cabbages, the leaf chichories (radicchio, escarole, endive, frisée), asian greens (bok choy, garland greens), kale, collards, arugula, mustards, mache, orach, cress, miner’s lettuce, salad burnet, spinach, chard, cauliflower, broccoli, kohlrabi, Brussels sprouts, rapini.
THE ROOT CROPS
Root crops are easy to grow, so long as the soil is loose and well-drained: radishes (don’t forget the delicious daikon radishes), beets, turnips, parsnip, carrots, root chicory, burdock.
Beans are not just for summer: peas, garbanzos, fava.
You can plant most perennial herbs (omitting the frost-tender crops) and many annual herbs: parsley, dill, chervil, cilantro, fennel, borage, and salad burnet.
CROPS WITHOUT CATEGORY
Some don’t fit neat into a category: celery, artichoke and cardoon, onions, garlic, strawberries, grapes, most fruit trees and perennial crops (if you plant citrus or other frost-tender crops, have a good plan for frost-protection).
Probably the easiest crop to grow, radishes are great for beginners. Plant from seed and thin to allow roots to grow to mature size. Radishes love loose, well-drained soil, especially the daikon varieties. Do not feed fertilizers high in nitrogen; the result will be lots of lush foliage and thin, underdeveloped roots. Japanese daikons take a lot longer to develop and need very nice, loose soil. Prepare the soil deeply if you wish to grow these.
Extremely productive, Swiss chard is also gorgeous. Some varieties (like the popular “bright lights”) splash the garden with exquisitely colorful stems—pink, lavender, red, and yellow. Plants take up quite a bit of room; seed at about a foot per plant and make sure they don’t shade out neighboring plants. They grow about 20 inches tall. Chard is best direct-seeded, and successional planting will keep you provided with younger, tender seedlings. Provide plants with average garden soil.
Bulb fennel requires very little to grow, except space. Soil can be average or even below average so long as there is regular water and the ground is loose. However, fennel grows best by itself, as other plants don’t like the chemicals fennel emits into the soil. Protect fennel from any hard frosts. Florence fennel is a good variety, producing meaty bulbs that are delicious roasted. ✜