Fall is the season for planting in the desert. Warm soils encourage roots to develop before the cold of winter settles in stalling growth. University of Arizona Extension studies have shown Fall planting helps new seedlings handle our hot summers as well with a solid understory foundation more readily adapting to our limited water. Several milkweeds (Desert Milkweed (Asclepias subulata), Arizona Milkweed (Asclepias angustifolia) and Pineleaf Milkweed (Asclepias linaria) are featured at many seasonal plant sales as are rich nectar sources like Desert Ageratum (Ageratumcorymbosum), Sweetbush (Bebbia juncea) or Lantana (Lantana camara). But don't forget herbs and wildflowers that attract our earliest butterflies during the cooler season as well.
Every winter a few monarchs spend the winter in the greater Phoenix and Yuma areas. These are likely monarchs that eclosed late in the season. Some may be breeding monarchs but many are in reproductive diapause and will delay mating until spring. Whether breeding or not, monarchs will need strong nectar to help sustain them during the cooler months.Winter blooming Fernleaf lavender is a monarch favorite. Calendulas are as well, so keep a few around in pots for monarchs that survive our light freezes in the area.
Wildflowers are easy to grow and many reseed for future seasons. Premier planting time in the lower deserts is from October through the end of November. Simply sprinkle seeds thinly and rake in. You can spread seeds over granite or soil. Small seeds may be easier to distribute mixed with sand. You can let nature take its course with our winter rains, or you can help secure a spring floral display by watering lightly until new growth is up. Only an occasional drink of water is needed if our rains are late. On warm winter days you may spot a few local butterflies visiting your patch before anything else is in bloom, a regal thank you for your effort.
Bakers Nursery in Phoenix has large vats of wildflower seeds you can purchase by the ounce that grow well in our Sonoran Desert. The Desert Botanical Garden Desert Botanical Garden Wildflower Sources is a handy resource to order seeds in time for planting as well. So think wildlife with wildflowers this winter and keep your eye out for out of season visitors to your yard.
Gail is the Monarch Watch Conservation Specialist for Arizona, the Coordinator of the SW Monarch Study and serves on the Board of Directors of the Monarch Butterfly Fund. She is also a trainer for the Monarch Larva Monitoring Project and participates in Monarch Health. A life-long gardener, Gail completed the Master Gardener Training in 1996 and the Desert Garden Mastership Program in 2011. She is also a volunteer for AZ State Parks, Rainlog, COCORAH, a storm spotter for the National Weather Service in Phoenix and a member of CAzBA (Central Arizona Butterfly Association). Her husband, Bob, joins in the fun and enjoys photographing wings and things in the field.