Collect branches in January and February
Nancy Shenk collects branches for forcing as she does her winter pruning. Forsythia is one of her favorites because it readily forces, even in the fall.
Photo/Illustration: Jennifer Brown
Many ornamental trees and shrubs set their flower buds during the previous growing season. These buds must experience a period of dormancy before they will open. After six weeks of cold temperatures, buds will usually come out of dormancy after two to three weeks of being exposed to warmth and moisture. Depending on your geographic location, usually by the time February arrives, most species suitable for forcing have experienced the required period of dormancy.
Coincidentally, late winter is the best time to prune deciduous trees and large shrubs. We usually head out into the yard with pruners in hand starting in January. We get a jump-start on our pruning along with an early gift of spring color inside our house. We prune our trees and shrubs for shape and to remove crossing branches and old or diseased wood. From the wood we have cut off the plant we select branches for forcing that are less than 1/2 inch in diameter and cut them to the desired length.
We like to prune on a mild winter day when the temperature is above freezing. Branches and buds are softer and more pliable and will be better able to make the transition from cold outdoor temperatures to warm indoor temperatures. We inspect the branches carefully when making our selections, looking for those with lots of plump flower buds. Flower buds are round and fat, whereas leaf buds are smaller and pointed. If we are not sure what type of bud we are looking at, we do a little bud surgery. When cut open, a flower bud will reveal miniature flower parts on the inside.