with Deryn Thorpe
Winter is rose pruning time, a task which rejuvenates the plant by producing new growth followed by flowers.
In the US roses are usually pruned lightly, by no more than two thirds, to encourage them to jump into bloom as soon as the weather warms in mid spring.
Roses are tough and they will still continue to display some flowers, even if we forget to prune them or hack them back in an inexpert way.
It is best to cut back roses according to their growth habits. Vigorous roses can be cut back by half to two thirds and most by not more than half. If you continually need to cut back more than two thirds, because they are too big, you have chosen the wrong rose for the space
Pruning basics for shrub roses
Pruning generally takes place from October until the beginning of December depending where you are in the US. In frosty areas pruning should not be undertaken until the threat of frost is past.
Traditionally roses are pruned just below a node or bud (little bumps on the stem) with cuts at a 35degree angle to the horizontal. It was believed that cuts should be done above outwards facing buds to encourage the rose to branch out in that direction. However research by both the American and British Rose Societies has shown that cutting in this way doesn't actually make any difference to the direction of shoot growth.
? Cut out all dead wood.
? Cut out all spindly growth less than pencil thickness
? Reduce the length of main branches by a third to a half.
? Completely remove one old stem (often grey in colour and unproductive) each year or so (depending on the vigor of the rose bush) on mature (4-years-old) bushes to encourage the rose to send out new water shoots from the base.
? Central canes are sometimes removed from vigorous roses to aid air flow which helps reduce possible fungal problems.
? Tough pair of gloves
? Sharp by-pass secateurs, long handled secateurs, hedge trimmers (for hedge roses), pruning saw
? Methylated spirits or bleach to sterilize tools between bushes
? You can use a powered hedge trimmer or chain saw but these make ragged cuts that should be trimmed off as they look ugly and can let infection into the rose.
Immediately after pruning spray bushes and the ground with copper oxychloride, Bordeaux mixture or lime sulfur. An alternative is to use your regular fungicide and insecticide. Do this immediately after pruning as some sprays will burn the new foliage.
The techniques for pruning climbing and rambling roses and some heritage roses are different so consult a specialist publication on rose pruning.