Let it Grow: Keep surprise frost in mind for plants

Published 12:00 am Tuesday, March 21, 2006

So, we&8217;re finally into spring.

Our typical &8220;last frost date&8221; is April 15, so if you are just dying to plant some warm weather annuals, you should be prepared to protect them from that surprise frost that may hit us at any time.

Some petunias and calibrachoas (million bells) can tolerate a light frost but not begonias.

A frost will bite them good and turn their tops to mush.

Though they may come back from the basal leaves and stems that were protected from the frost, the maturity of the begonia will be delayed beyond what it would be if you just waited a couple more weeks to plant them.

Alyssum (Lobularia maritima), Dusty Miller (Senecio cineraria) and Annual Dianthus (Dianthus hybrida) can tolerate cooler temperatures; even some light frost.

I have grown the dianthus in Shelby County and they have spread out to make a good-looking ground cover.

The frosts didn&8217;t seem to bother them and with proper maintenance, (deadheading) they bloomed from early spring until fall.

Helichrysum comes in a variety of colors, from silvery gray (licorice plant) to chartreuse (Limelight).

I have found that the helichrysum can tolerate some heavy frost.

If there is tender young growth on the tips though, it could get a little frostbite.

These plants make, not only good bedding plants, but great container mixers and hanging basket plants.

Snapdragons (Antirrhinum sp.) make great cool weather plants.

Though the central Alabama sun tends to beat them up a little in the heat of August, these plants are semi-hardy. You can use them as a garden element for height or buy the cascading varieties for hanging containers.

Verbena hybrids are also semi-hardy here in Shelby County. Some are even considered to be perennials such as the Homestead cultivar.

Whichever plants you choose, consider the fact that we will probably have another frost or two before Easter. Read the tags in the plant pots. They provide a lot of information about sun and water requirements as well as the plant&8217;s hardiness.

Also, you can go to the Home Grown Tomatoes website and link to Alabama Grown for more plant information on the annuals you&8217;re looking for this spring