Osteospermum, dianthus and petunias.

Snowbirds will soon begin to return to the Coachella Valley. Once they arrive, they’ll be quickly reminded of their pre-summer departure, as they find empty pots around their home.

One of the first items on the agenda after unpacking: Planning new gardens!

We’ll soon enter one of those periods of time between winter and summer known in most regions as “fall.” The comfortable temperature months of September and April can try our patience as we seek out flowers to plant in our now-tired pots. Often, our selection is somewhat limited, considering it may not truly be time to plant yet.

These are what I call the “shoulder seasons” of desert gardening. We should hold off on planting some things until nighttime temperatures reach levels that are just a bit cooler. Growers cannot push out plants that will succumb to the heat too early: We need night temps to get out of the 60s to plant true winter flowers. Yes, it is the nighttime temperature that dictates our planting cycles: As long as the plants can be warm or cool enough at night (depending on the season), they can handle the days’ swings between 70 and 90.

Even though some nurseries may have winter flowers on offer such as pansies, violas and ornamental kale, if we plant them too soon, they will struggle to survive, often succumbing to the constant heat in September and early October. Pansies get leggy and weak. Kale bolts early.

However, if we are patient and use flowers that can withstand the challenges of our long summer, we will be rewarded with stunning potted gardens.

To help desert residents enjoy potted color 365 days a year, I have created a short list of flowers and complementary plants that will thrive during the shoulder season—and often make it through much of the following season, too. Many of these flowers are becoming increasingly available during all seasons. Under the right conditions, they might hang on longer and longer. The “right” conditions typically mean receiving afternoon shade or filtered sun during the eight to nine warmer months. They will certainly stand up to the low desert’s cooler temperatures in the winter:

  • Alyssum
  • Bacopa (shade perennial)
  • Dianthus
  • Dusty miller (complementary plant)
  • Geraniums (best in morning sun only; no sun in the summer)
  • Marigolds
  • Osteospermum
  • Petunias
  • Snapdragons

You can see some attractive combinations in the accompanying pictures. Using the taller varieties such as osteos and snapdragons as center or backbone plants will give you some great height to start your arrangement. Dianthus also comes in some newer hybrids, including “Amazon,” where heights far exceed the standard 8-to-10 inches of older varieties.

Next in your pot should be mid-height plants such as the dusty miller, marigolds and petunias. As you know, petunias will also trail, so don’t put anything between them and the pot’s edge.

Lastly, alyssum and bacopa are your true trailers. Bacopa will not tolerate the strong desert sun, so keep it in the shade or on the shady side of the pot.

Follow along at CVIndependent.com this month as I share more information with you about the coming shoulder season in the desert!

Marylee Pangman is the founder and former owner of The Contained Gardener in Tucson, Ariz. She has become known as the desert’s potted garden expert. She is available for digital consultations, and you can email her with comments and questions at potteddesert@gmail.com. Follow the Potted Desert at facebook.com/potteddesert. Get a free copy of Ten Top Tips to Desert Potted Garden Success by visiting www.potteddesert.com/m. The Potted Desert Garden appears Tuesdays at CVIndependent.com. Below: Snapdragons, petunias and dusty miller; geraniums, alyssum and bacopa.