Sunday 20 October 2019

Winter rose pruning is important

Andrew Collyer.
Andrew Collyer.

By Andrew Collyer - Practical Gardening

Rosa rugosa 'Hansa' repeat flowers, autumn colour, winter hips.

Repeat flowering roses, these are roses that flower more than once in a season, have been exceptional this year for their late flowering. I still have blooms on various varieties including Margaret Merril, Graham Thomas, A Shropshire lad, Bonica, Molinuex and all the Flower Carpet types I grow. But because of the recent windy weather conditions I think it is finally time to winter prune and sacrifice the last few remaining buds, these probably wont make it to flowering anyway, and because any existing flowers have been now been destroyed.

With roses we tend to prune twice, once in late autumn then again in the spring. The winter pruning is done largely to stop the strong winter winds rocking the plant on its rootstock. Roses tend to have few fibrous roots and are prone to loosening in the soil over winter. This wrenching and twisting in the wind causes damage to the root system which in turn may encourage diseases into the plant. Winter pruning also presents a tidier winter look.

Winter pruning can be carried out on any repeat flowering roses. Hybrid tea, floribunda, English, groundcover and repeat flowering shrub roses. Once flowering shrub roses don't need annual pruning at all, deadheading is enough. If you want to prune them to control their size do this after they have flowered in the summer.

When winter pruning your repeat flowerers what you are really looking to do is reduce the overall size of the plant and to remove any crossing or touching stems that might rub and cause damage over winter. In spring you will be looking to shape up and structure the rose so don't be too concerned about that at winter pruning.

So we are looking to cut back the rose to about 40 centimetres leaving some additional length to work on at spring pruning when hybrid teas will be cut back to as low as 10-15 centimetres floribundas and English roses to about 30 centimetres. The reason we want this additional length is to allow for the pruning off of any frost damage or die back incurred over winter. With climbers look to remove any very old wood and replace with some fresh new strong growth from the base of the plant. Remove any weak straggly growth. Cut back any growth coming from off your main structural framework to around 15 centimetres. When structuring your climber try to fan out the branches as near to horizontal as possible as this encourages more buds to form in summer. With rambling roses prune only for control.

During this pruning process you will end up with what might appear to be many seemingly useless rose stems. But these are not as useless as you might think as they will make great material for hardwood cuttings. Bought roses all come from budded stock, this is cutting out a bud from a cultivated rose and via an incision inserting it onto a wild or selected rootstock. This is supposed to produce a stronger healthier plant but recent research may confound this idea. All roses can be grown very sucessfully from hardwood cutting, I've done it myself. Some varieties may be better at ' taking' than others but you can expect a 70% sucess rate.

To take your cutting look for a healthy stem about pencil thick. Make a 20 centimetre length by cutting just under and just over a visible bud. Make sure you remember which way is up ! Dip the bottom 5 centimetres of the cutting in a rooting compound, not essential, and then push into loosened soil to half the cuttings depth. This can be done in pots as well.

Now you have to be patient as you will have to wait until next winter to lift your new rose plant. If you want you can put the unrooted cutting in the position you intend to plant it and just leave it there once rooted. You will have to keep the area weed free and also don't allow the cutting to flower this first year. You want as much energy to go into root making as possible.

Check tree stakes and ties.

Wexford People

Most Read