Answer: I don't know any low desert gardeners who have continued success with dahlias, so I don't recommend them here. Gladiolas can survive and even naturalize if conditions are to their liking, but again, not many people have regular success with them. Typical spring bloomers, such as daffodils and crocus need pre-chilling, but summer bloomers, such as canna, do not. A great bulb plant that you might want to consider is rain lily (Zephyranthes). It grows without fuss, will spread, and will take sun. Bearded iris and Dutch iris also do extremely well, as do crinum, or spider lilies.
Here are several companies that specialize in bulbs. Check with them to see if you can get shipping when you need it:
Van Bourgondien, 1-800-622-9959, email@example.com
Brent and Becky's Bulbs, http://www.brentandbeckysbulbs.com
McClure & Zimmerman, http://www.mzbulb.com
Also, check with local full-service nurseries in the fall. I've noticed that more types of bulbs are showing up than in previous years and they arrive at the appropriate time!
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