Transplant Landscape Plants
Fall is the perfect time for transplanting trees, shrubs, vines, ground covers, perennials, cacti, agave, and aloe into the landscape. Root systems have seven or eight months to develop before summer heat hits. Dig a planting hole as deep as the root ball and three to five times as wide. This wide area promotes good root spread into the surrounding soil. It is no longer recommended to amend the backfill.
Some herbs are easy to propagate by layering this month, including lavender, marjoram, oregano, rosemary, santolina, thyme, and Mexican tarragon. Carefully bend a low-growing stem over into the nearby soil so it stays buried. Keep the area somewhat moist, but not overly wet as most herbs will rot in soil that is too wet. After 4 to 8 weeks the stem will develop roots and the baby plant can be cut loose from the mother and planted elsewhere.
Watch for Caterpillar Migrations
Armyworms, white-lined sphinx caterpillars, and salt marsh caterpillars sometimes migrate in huge numbers at this time of year, seeking a place to pupate. They don't do much damage to plants, but can be a nuisance because they fall into pools, virtually covering the surface of the water, or blanket landscapes and driveways. Their numbers will drop naturally so other than clean-up, no control is needed.
Clean Up Gardens
Save seeds for sowing next year. Pull spent warm-season flowers and vegetables and put them in the compost. Turn compost and remoisten. Check agaves for signs of rotting and collapse. This signals they've been attacked by agave weevils and must be completely dug and put in the trash.
Sow Wildflower Seeds
Wildflowers need a sunny location. Choose seeds native to your area. Mix seeds with sand to promote uniform sowing. Very lightly rake the area. Too much raking disturbs weed seeds, encouraging them to germinate. Do not cover wildflower seeds any deeper than 1/16 of an inch. Keep soil moist for about 4 to 6 weeks until seeds germinate and reach about 2 inches in height. Soak the area every few weeks, if needed. If winter rains are heavy, this won't be necessary.