Answer: There are two distinct growing seasons in the low desert with different annuals thriving in each season. There's a cool season from approximately the end of September through April. Annuals can be installed from September to February. The warm season starts with planting in mid to late February. Some warm-season plants will make it through the summer's heat; others will end their growth when the heat arrives.
Lots of flowers can be planted for enjoyment from late September through April. Some of my favorite easy-to-grow annuals include calendula, bachelor's button, pansies and violas, nasturiums, stock, snapdragons, alyssum, dusty miller, poppies and dianthus to name a few. Wildflowers are also seeded in the fall for spring bloom. (October is a good month for sowing wildflowers.) Most of these are sun lovers.
Bulbs might be a good choice in the shady area, as they appreciate shade in the summer. Bulbs that do well here include ranunculus, tritonia, iris, amaryllis, spider lily and rain lily.
A good reference book that contains planting calendars for the low desert is called "Desert Gardening for Beginners: How to Grow Vegetables, Flowers and Herbs in an Arid Climate." ISBN 0-9651987-2-3. Good luck!
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