Deadheading prolongs flowering season, improves appearance

Q. What does deadheading mean?

A. Deadheading flowers is simply the process of removing spent flower blooms in order to extend their flowering season and improve their appearance. Once the flowers have been pollinated, their job is done and they will start to form seed heads and drop their petals - nature then directs all the plants energy into growing the seed heads.

Deadhead annuals such as zinnias, marigolds, and cosmos to keep them blooming throughout the growing season. Deadheading perennials channels the energy that would have been spent on seed production into root growth. When you deadhead, remove the whole flower, not just the faded petals. The part that forms the seeds is usually at the base of the flower and that's the part you need to remove.

There are several methods of deadheading. You can use your finger and thumb on some plants to nip off the dead flowers if their stems are not too tough. If the stems are too tough to pinch back with your fingers, use scissors or pruners to cut off the flower heads.

Note that deadheading has three drawbacks. First, when you remove the spent bloom, you are removing the seeds. Therefore, don't deadhead the plants if you want to save their seeds. Secondly, removing seed heads may deprive seed-eating birds of their favorite food - and deprive the gardener of the company of the birds. Finally, plants such as Rudbeckia and Autumn Joy Sedum (Sedum x Autumn Joy) have ornamental seed heads that enliven a garden in the fall and winter.

Q. Does washing off frost in the morning before sunlight protect plants from injury?

A. Frost is nature's way of bringing the growing season to a close. In the Chicago area, the first frost usually occurs around mid-October.

Plantings close to the foundation of your home often survive a first frost because of the heat given off from the house. However, the best way to protect your other plants is by either covering them if you know a frost is predicted, or for potted plants, moving them to a sheltered location such as a garage.

Cover your plants with blankets, newspaper, straw, sheets, tarps, boxes, or plastic sheeting. Apply the covers late in the afternoon and remove them in the morning. Floating row covers can also protect plants. Plus, you can leave the covers on the plants, since the covers allow sunlight to shine through. Watering the garden before a frost will also offer some protection since wet soil holds four times more heat than dry soil.

However, no matter what you do to protect your plants from frost, eventually the growing season comes to an end.

• Provided by Mary Boldan, University of Illinois Extension Master Gardener. Send questions to Ask a Master Gardener, c/o Friendship Park Conservatory, 395 W. Algonquin Road, Des Plaines, IL 60016, (847) 298-3502 or via e-mail to cookcountymg@sbcglobal.net.