Sunday 11 January 2009

Shrub Pruing Basics, Part 1, When to Prune

Landscapes make our houses into homes. Trees and shrubs not only contribute pleasant feelings to our surroundings they add up to 15% to the value of your property.

It often takes several years for newly planted shrubs to establish and then before you know it they are on their way to becoming leggy overgrown monsters.

Most shrubs will appreciate even the smallest amount of pruning and reward you with rejuvenated foliage and more abundant buds.

Time to prune

The first key to correctly pruning your shrub is to know what you are growing. Proper identification is essential to correctly prune your shrub. Many shrubs flower on last year's growth and if you are pruning yearly you may never get flowers. The classic example of this is the lilac. Shrubs like these should only be pruned immediately after they bloom to ensure a good set of flower buds for next year.

In contrast to the old wood flowerers some shrubs only bloom on this years new growth. These shrubs should be pruned before the growing season begins.

As with so much of nature there are shrubs that don't fall into either of these categories and flower from both last years growth and this years growth. These typically flower later in the growing season and can be pruned while dormant or right after blooming.

Pruning Chart

Location of Flowers

Best Time to Prune

Typical Plants

Last Years Growth

Right After Flowering

Lilac Forsythia Saskatoon

New Growth

Before Growing Season

Clematis Spirea Hydrangea

New and Old

Right After Flowering or While Dormant

Potentilla Rose

Mock Orange

There are some shrubs that we grow primarily for foliage, like red osier dogwood, elderberry, willows, and barberry. This group should generally be pruned in the winter season before growth begins. Moose prune their dogwoods in the winter and so should you.

Most conifers like spruce, juniper and cedars can be pruned at anytime with the exception of pines. Pines are best pruned in early summer when the new growth is emerging. These long shoots known as candles can be cut or pinched off at the half way point and the shrub will set new buds for future growth. If you prune pines after the shoot has fully elongated and you will be left with a half shoot. Without buds on the end it will loose its needles and leave you with a dead stick.

Contact your certified Arborist for more information on shrub pruning and watch for the second part of this article dealing with tools and techniques.