Callaway gardening column: Preparing petunias

Although it may be hard to think about planting flowers when it is snowing, the time for starting several varieties is fast approaching. Geraniums, impatiens, lobelia and petunias all need to be started in February to be ready to plant in the spring after the danger of frost has passed.

Of course you can buy petunias at your local garden center or greenhouse in the spring but then what would you do on a cold, snowy February day? So today I'll talk about starting petunias indoors. Petunias are one of the most popular flowering annuals and they need to be started mid- to late February. Part of the reason petunias are so popular is because they are easy to grow and bloom reliably all summer long.

Petunias come in a wide range of colors, flower forms (large, small, single, double, etc.) and growth habits (compact to spreading). With such a wide variety to choose from, be sure to plan your area before you buy.

Start with clean good containers. If the containers have been previously used, wash them in soapy water and disinfect them by with a solution of one part chlorine bleach and nine parts water.

Next, fill the container within an inch from the top with a good germination mix and press lightly to firm. Moisten the germination mix with a fine spray or sprinkler. It may take several applications of water, waiting several minutes between applications, for the soil to become damp.

Now it's time to sow the seeds. Petunia seeds are very small and can be difficult to handle. Fortunately, pelleted seeds are sometimes available. Buy them if possible. Carefully sow the seeds on the soil surface, and then gently press the seeds into the germination mix with a pencil or a small block of wood; be sure the seeds do not stick to the wood. Petunia seeds require light for germination so don't bury or cover them - this is very important. After sowing, thoroughly moisten with a sprinkler.

To maintain moisture levels, place a piece of plastic food wrap or something similar over the container. To get optimum seed germination, place the container in a warm, 75 to 80 degree location with plenty of bright light but not in direct sunlight with the plastic cover on. Petunia seeds will germinate in seven to 10 days. Remove the plastic cover as soon as germinations starts (as soon as you see a sprout).

Place the seedlings under fluorescent lights or in a sunny window. Regular fluorescent shop lights can be used, should be no more than 4 to 6 inches above the plants and should be left on for 12 to 16 hours. Transplant the seedlings into plastic cell packs, peat pots or other containers when the seedlings have two to three true leaves. To grow stocky plants, grow the plants in a cool location under fluorescent lights or in a sunny window. It is a good idea to allow the potting mix to become slightly dry between waterings. Use a diluted fertilizer solution every couple of weeks to feed the plants.

Now you'll have something to do the rest of the winter... take care of the plants you just started.

Peter Sutter is a lifelong gardening enthusiast and a participant in the MU Extension's Callaway County Master Gardener program. Gardening questions can be sent to [email protected].