We have hundreds of varieties of annuals that are so ready to be planted; you’ll have to be careful they don’t jump in the car with you. Several varieties can go in the ground now: Alyssum, Petunia, and Snapdragon, to name a few. The rest of the annuals are also ready to be planted, the catch is the weather. Many customers have a greenhouse, hothouse, or sunroom. If you aren’t lucky enough to have one of these, you can still keep annuals protected from frost by using a number of methods.
Bring plants in at night. Let them get used to their future environs by day, whether it’s a full sun or shady spot. Then bring them into a garage or some other enclosed place at night that will not be affected by frost. Some customers ask if they can just keep their plants in the garage until it gets warm. No. Not unless your garage has big windows that let a lot of light in. Even shade plants don’t want to be left in a cold dark garage for a month or even a couple weeks. Providing your plants with a set of wheels can help make it less of a chore. Keep containers on coasters, or pots and flats in a wagon for ease of transport.
Consider building a small shelter. A simple cold frame can be built by hinging a window to one side of an open bottomed box, built from plywood or scrap lumber. A small hoop house made from pvc pipe and flexible plastic is light weight and portable. If you don’t want to build anything there are small, premade greenhouses sold at many garden centers. When choosing any of these options remember to give the plants adequate ventilation. Think about how stifling it can get in your car when a cloudy day turns to a clear sky. It’s the same for these little shelters. Let the plants breathe!
Finally, for the gardener who just wants to get it done; tuck those babies in at night! It’s risky but just providing the smallest bit of protection during the colder nights can help keep tender leaves and roots unstressed and focused on growing. A bucket, blanket, pillow case, or plastic trash bag can be used to put over plants. Just make sure it’s not heavy enough to crush stems.