- Plant desert–adapted trees, shrubs, vines, and groundcovers.
- Plant warm-season flowers such as melampodium, hollyhock, salvia, verbena, and zinnia (in the low desert).
- Sow seeds for cucumbers, melons, and summer squash (in the low desert).
- Set out transplants of eggplant, tomatoes, and peppers at month’s end.
- Adjust drip irrigation frequency as the weather warms.
- Plant agaves in landscapes and gardens.
- Add juicy edibles such as sweet oranges, grapefruit, tangerines, tangelos, and lemons and limes.
- Plant heat-loving woody shrubs such as Arizona rosewood (Vaquelinia californica).
- Spread a 4–6 inch layer of mulch (either an inorganic gravel or an organic mulch such as shredded bark) around plantings.
- Fertilize citrus trees with a citrus-specific fertilizer.
- Plant cactus and succulents such as golden barrel cactus.
- Add desert spoon and yucca plants to your landscape.
- Gain landscape height with vines such as Carolina jessamine, Lady Banks’ rose, and Virginia creeper.
- Set out transplants of cosmos, Mexican hat, and portulaca.
- Plant shrubs such as Baja fairy duster (Calliandra californica).
- Fertilize cactus and succulents with a cactus and succulent fertilizer.
- Plant palms such as Mexican blue palm (Brahea armata) and Canary Island date palm.
- Create a Bermuda grass lawn through seed, sod, or stolons.
- Sow seeds for cucumbers, okara, melons, and summer squash.
- Monitor the water needs of new plants as summer heat arrives in earnest.
- Divide and transplant prickly pear cactus and agaves.
- Kill aphids by spraying them with insecticidal soap.
- Plant cactus such as golden barrel and torch cactus.
- Pot up summer annuals such as celosia, globe amaranth, and lisianthus.
- Plant heat-loving trees and shrubs such as Texas ebony and Texas Mt. Laurel.
- Sow seeds of traditional southwest “monsoon” crops such as, beans, corn, melons, and squash.
- Spray off cochineal scale on prickly pear with a strong jet of water.
- Rejuvenate tomatoes. Cut back tomato vines to 1 foot high, fertilize, and water deeply for a bigger fall crop.
- Lay sod. Roll out new Bermuda grass sod while temperatures are still hot.
- Plant aromatic species. Try copper canyon daisy, golden dogbane, creosote bush, and trailing indigo bush to bring scent to your yard.
- Sow pumpkin seeds early in the month.
- Add an 8-inch layer of compost to vegetable beds to keep roots cool, provide nutrients, and preserve soil moisture.
- Plant ocotillo. The large wands add drama to any desert garden. Select container plants -- rather than bare-root specimens -- for much better transplant success.
- Plant ornamental grasses such as deer grass, Mexican feather grass, and ‘Regal Mist’ grass.
- Fertilize citrus trees. Early in the month, give citrus trees their last dose of fertilizer for the season.
- Plant garlic cloves now for a crop that will mature in spring. Plant each clove pointy side up, 2 inches deep, and 6 inches apart.
- Sow sweet peas late in the month. Try ‘Electric Blue’, ‘Pastel Sunset’, and ‘Watermelon’.
- Sow wildflowers. Remove weeds, break up the soil with a heavy rake, and then scatter seeds. Try desert marigold, globemallow, Mexican gold poppy, firewheel, tidy tips, desert lupine, five spot, Parry’s penstemon and owl’s clover.
- Plant hardy perennial flowers such as native angelita daisy, damianita daisy, autumn sage, fern-leaf lavender, and Palmer’s penstemon.
- Start cool-season veggies. Sow bok choi, carrots, peas, radishes, salad greens, Swiss chard, and turnips. If you missed planting garlic in September, plant cloves now.
- Prepare for the first frost. Purchase quilted frost cloth to have on hand to cover tender plants.
- Force bulbs now for indoor display around the holidays. Refrigerate daffodils, hyacinths, and paperwhite narcissus for eight weeks. Plant them in containers filled with potting soil and place in a cool, low-light location. In a week, move to a warm, sunny room to bloom.
- Harvest pomegranates. Begin harvesting ripe pomegranates and keep them refrigerated for use in Thanksgiving salads.
- Plant Mediterranean shrubs and trees. Try germander, lavender, rosemary, bush morning glory, and ‘Wilson’ fruitless olives for winter foliage and fragrance.
- Apply pre-emergent herbicide. To prevent weed seeds from germinating, use a pre-emergent such as corn gluten (don’t do this if you have wildflower seeds in your soil).
- Plant winter annuals such as chrysanthemum, cyclamen, dianthus, Johnny-jump-up, pansy, snapdragon, and sweet alyssum.
- Protect citrus with a frost cloth when temperatures dip below 30 degrees. If extreme cold is forecast, cover the canopy with a quilted frost cloth, wrap the trunk in burlap, and place a light near the trunk but not against it.
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