You Can Master Pruning ~ Part 1: Spring-blooming Shrubs
Posted Apr 14 2009 11:49pm
Every branch in Me that does not bear fruit He takes away, and every branch that bears fruit He prunes, that it may bear more fruit. (John 15:2 NKJV)
To most gardeners, pruning is a daunting gardening tasks. But, knowing when to prune and how much to prune can be both a labor-saving and artistic outlet. Being diligent to prune at the correct time and with the correct methods will keep your garden tamed and your work pleasurable.
Prune with a Purpose: Good pruning is the selective removal of branches without changing the plant's natural appearance or habit.
Keeping Plants Healthy and Attractive
Developing a sound framework through proper thinning helps prevent disease and loss of vigor while it maintains good form.
* Remove dead, dying, or diseased wood. * Cut out unwanted growth, like watersprouts and sucker shoots. * Prune out crossing or rubbing stems. * Thin out stems to open the plant to light and air. * Remove any overly long or awkward-looking shoots.
Controlling Plant Size
Over time, trees and shrubs often grow to sizes that exceed the space allowed them. Careful planning of your landscape and spacing your plants properly will let your garden grow without needing too much of this kind of pruning. Before you grab your loping shears, look for these things:
* Plants that you need to keep to a certain size, like a hedge or a shrub in a foundation planting. * Plants that are crowded into other plants. * Stems that are leaning into paths, walkways, or doorways, making it difficult or dangerous to pass by. * Plants that are too big for the space you have.
Improving Flowering and Fruiting
Most flowering shrubs will bloom either on one-year old growth or on new growth. Properly timed pruning increases the production of wood that will bear flowers. Using good pruning techniques with flowering and fruiting plants is the most important step to maximize their production. This kind of pruning involves:
* Thinning cuts to remove crowded stems and to open a plant to light and air. * Removing old wood to encourage vigorous new growth and more flowers. * Taking out dead and unproductive wood.
Know When to Prune
For the rest of today's column, let's look at my oldest daughter's favorite plant. She loves forsythia shrubs (Forsythia species) because they always burst into bloom in our area just in time to celebrate her late-March birthday. With proper upkeep this early-spring bloomer can be a spectacular addition to your landscape.
This shrub has an arching, fountain-type growth habit. The bright yellow flowers generally appear in early spring before the leaves.
Trying to turn this fountain-shaped plant into a ball-shaped plant will result in increased pruning tasks and a decrease in flowering over time.
Forsythia blooms on the previous year's growth. You should prune it in late spring, just after it finishes flowering. If you wait to prune in summer, fall, or winter, the pruning will remove the flower buds, reducing or eliminating the next spring's blooms. Neglecting to prune forsythia results in flowering and leafing on a few thin, new stems and a dense plant where light and air cannot penetrate.
Thankfully forsythia is a very forgiving plant. applying the following good pruning techniques will result in a very lovely show:
Cut 1/4 to 1/3 of the oldest stems to the ground each year to encourage the production of vigorous new stems. In three to four years of proper pruning you will have removed all the offending stems.
If you want a quicker overall rejuvenation, you can cut all the stems to a few inches above the ground. It will take a few years to fill out and reach it's full size (up to 8' tall and 5'-10' wide).
These other shrubs also bloom on last season's growth:
Eastern redbud (Cercis canadensis), Japanese quince (Chaenomeles japonica), Whitefringe tree (Chionanthus virginicus), Spring flowering deutzia (Deutzia species), Pearlbush (Exochorda reacemosa), Kerria (Kerria japonica), Honeysuckle (Lonicera species), Star magnolia (Magnolia stellata), Mockorange (Philadephus species), Andromeda (Pieris species), Azalea and rhododendron (Rhododendron species), Rambling rose (Rosa species), Early white spirea (Spirea species), Lilac species (Syringa species), Small-flowered tamarix (Tamarix parviflora), Viburnum (Viburnum species), Old-fashioned weigela (Weigela florida).
Some shrubs that bloom after June usually do so from buds formed on shoots that grow the same spring. Such shrubs should be pruned in late winter to promote vigorous shoot growth in the spring. Shrubs that bloom on current seasons growth:
Glossy abelia (Abelia x grandiflora), Butterfly bush (Buddleia davidii), Japanese beauty bush (Callicarpa japonica), Bluebeard (Caryopteris x clandonensis), Summersweet (Clethra alnifolia), Shrub althea (Hibiscus syriacus), St. Johnswort (Hypericum species), Bush rose (Rosa species), Anthoy waterer spirea (Spiraea bumalda 'Anthony Waterer') Mikado spirea (Spiraea japonica), Coralberry and snowberry (Symphoricarpos), Chaste tree (Vitex angus-castus).
Next week we will look at pruning fruits, nuts, and berries.