MARCH
2004

 

 

 

By
Beverly Shaw
 
Advanced
Master Gardener
Purdue University

 

 

 

 

 

03-04-04

Question and Answer

Q.  I live in an older home with established bushes and trees. Last year, they started getting a bit wild and unruly. I don't want to use hedge shears to trim plants into tight shapes. I'd rather have a natural look but don't want to trim all summer. Do you have any suggestions? -- Larry Osborne, Fort Wayne, Ind.

A.  The dormant season is a great time to prune many shrubs. Landscape plants should be pruned to maintain or reduce their size, to remove undesirable growth, to remove dead or damaged branches, and to rejuvenate older plants to produce more vigorous foliage, flowers, and fruits.

Late winter or early spring is considered to be the optimum time to prune most plants, since the plant's wounds heal quickly without the threat of insect or disease infection. However, plants that bloom in early spring, such as forsythia, magnolia and crab apples, should be pruned later, after their blooms fade. These early bloomers produce their flower buds on last year's wood, so pruning early would remove many potential blooms. Trees that have large quantities of sap in the spring, such as maple, birch and dogwood, are not harmed by early-spring pruning but can be pruned in late spring or early summer to avoid the sap bleeding.

If you want to reduce the size of a plant, a technique called "heading back" is recommended. Shorten branches by cutting back to a healthy-side bud or branch that is pointing in the direction you want future growth to occur. Make your cut about one-fourth inch above the bud or branch.

Rejuvenation pruning is one way to invigorate plants. It's a great technique for plants that have become large and leggy and are producing fewer flowers, or the flowers are up too high to enjoy. Remove one-third of the largest branches down near the ground. Next spring, remove another third. The following year, remove the last third. This way, you will have caused the plant to rejuvenate itself, increased flower production and decreased the overall size of the shrub. This is ideal for large Viburnum, lilacs and burning bush, among others.

Some shrubs (not all) can tolerate the most severe pruning -- cutting the branches down at ground level. This includes rose of Sharon, lilac, forsythia and spirea.

Contact your Purdue Extension office in your county and request a copy of HO-4, "Pruning Ornamental Trees and Shrubs," or get a copy online at http://www.hort.purdue.edu/ext/HO-4.pdf. It contains lists of plants that should be pruned after flowering and those that can tolerate rejuvenation pruning, illustrates how to make proper cuts, and more!

Q. I didn't plant all my bulbs last fall. I stored them in my garage this winter in mesh bags. Most of them seem to be OK. Are they salvageable? Thanks!

A. Most bulbs require 10-13 weeks of cold temperatures, about 40 F, in order to initiate flower buds. They also use the cool, fall season to initiate root formation before top growth begins. Your bulbs have not had those opportunities, but it still may be worthwhile to drop them in the ground.

Proper storage conditions to keep the bulbs cool and dry are often hard to find in the home environment. The bulbs usually begin to soften and rot or may actually sprout before they get planted. Even under ideal storage conditions, the bulbs will lose some of their food reserves through the natural process of respiration, the breaking down of stored carbohydrates as fuel for growth.

First, sort them out and discard any that are mushy or hollow. Plant the rest as soon as the ground is workable. Without an adequate chilling period, they will not bloom this year, but may gain strength and bloom in future years. Since the survival rate will be spotty, these bulbs will be best planted in a casual, cottage part of your landscape. Don't count on them to form a nice thick block of color. Leave any foliage in place until it yellows so it can photosynthesize and regain strength for future years.

 

Contact: B. Rosie Lerner
Editor: Olivia Maddox,