Winter pruning encourages healthy and vigorous growth for the next season
July is pruning time. A good pruning will encourage growth of healthy foliage and gives plants a boost for the next growing season. Diseased or damaged wood can hamper a plant’s growth, so by removing this, you give the plant a new lease on life.
Pruning can also shape a plant to fit a particular space, trim it into a desired form for aesthetic purposes, and improve the flow of air around plants. Pruning large trees and shrubs may become necessary to reduce size to open up the under-story to the sun.
Plants to prune in winter
What and when to prune depends on the species of plant. The general rule is pruning in mid to late winter before the next growing season, but this is not a set rule. If you are unsure, speak to your local nursery. Autumn and winter flowering shrubs can be cut back as soon as their flowering season ends.
Tender shrubs in frost areas should be pruned closer to spring. Do not prune spring flowering shrubs now. Deciduous tree are best pruned in winter when branches are bare. Cut for shape and remove dead or damaged branches. Also look for branches that cross or rub up against each other and remove these.
When tackling larger trees, consider your equipment and the size of the branches to be removed. Always put safety first. If you cannot guarantee a heavy limb can be cut and lowered safely to the ground, rather contact a tree felling company. Deciduous fruit trees can be pruned from mid-winter.
Before the new season’s growth, spray with lime sulphur to kill pests. For lemon trees, consider a light trim for shape and remove any diseased or poorly positioned branches. If you accidentally prune an established plant at the “wrong” time, it is unlikely to suffer any ill effect and will bounce back when the growing season begins.
Tools for pruning
◆ Secateurs are needed for smaller branches up to 25mm thick.
◆ Loppers are best for branches under 50mm thick.
◆ A pruning saw will cut through branches more than 30mm thick and a bow saw is best for thicker branches.
◆ Hedge shears are handy for keeping hedges and evergreen shrubs neatly trimmed. Electric hedge trimmers are a worthwhile investment if you have a number of hedges in your garden.
Pruning cuts should be clean for faster healing, so tools must be sharp. During pruning, wipe blades with a damp cloth before moving on to the next plant.
If you have trimmed a diseased branch, clean the tool with rubbing alcohol before tackling the next branch. If moving parts catch, use a lubricant spray to loosen up. Wash tools in soapy water and dry well after use.
Roses: Rose expert Ludwig Taschner says the best time for pruning roses is during July, but this should be delayed to the end of the month in winter rainfall areas. “A light pruning removes the inside twigs and even older main stems that are not showing much new growth from the last season,” explains Taschner.
“More normal or even severe pruning usually requires the bush to be cut down to hip or knee height with most of the side stems trimmed off.”
Taschner offers the following rose pruning and after care advice for bush roses:
◆ To do the job, you’ll need sharp secateurs, a long-handled lopper and good quality gloves.
◆ Cut off all top growth at a level between hip or chest height. This allows a look into the centre of the bush.
◆ Proceed to cut out older stems and thin growth.
◆ Retain and shorten three to five main stems, even reducing the younger, previous season’s stems by half and shortening several side stems. This will result in lots of flowers, with a medium stem length and flower size.
◆ The smallest wound is a straight cut across the stem. Sealing the cuts isn’t necessary. The remaining stems are hard wood and are unlikely to rot with water standing on the cut.
◆ Deep watering after pruning is essential for dried out soils in the rose bed. Water at least once a week until the end August.
◆ You can fertilise your roses immediately after pruning or by the end of August.
◆ If your soil requires enrichment, after pruning is the best time to do this. The roots are still inactive and by digging around the rose, loosening or even cutting roots encourages the rose to make new roots into a better environment. Compost may be dug in to a depth of 30cm. Also add a slow release fertiliser, such as Vigolonger, and mix in well.