By Jonathan Diaper
As I write, this mild weather and sudden spring lends urgency to those winter and early spring jobs that are yet to be done. Case in point, roses are beginning to shoot presumptuously. I like to have any rose pruning completed before they shoot into life, feeling that the plant’s energy is wasted if the fresh green shoots are destined only to be cut out. Roses are tough old darlings though, so don’t be afraid to prune them if they have already started to grow.
Generally speaking, it is advisable to prune shrub roses and climbing roses when they are dormant. I think of this as taking them by surprise. With the benefit of some hard frosts, the leaves will have dropped, making the job of deciding which dead or wayward stems to remove much easier. With this mild winter, however, many roses have stubbornly clung onto their leaves. These will drop as new shoots form, so carry on pruning as usual. It is not necessary to prune a climber in the first couple of years, as long as the stems are going to be tied-in.
The difference between a rambler and climbing rose is that people tend to be scared of the rambler. A climbing rose flowers on stems produced on the current year’s growth. A rambler flowers on the previous year’s growth. A rambler should be pruned soon after flowering so as not to reduce next year’s blooms. Don’t discount ramblers, they are tough and healthy, and add natural beauty to a garden. Some rambling roses can grow to be enormous, so ensure you have the space if you choose these varieties. However, it is important to know that not all ramblers are the same and some varieties could be ideal for their laidback elegance.
Climbing roses vary in vigour. Sometimes it pays to be pragmatic: if there are few (or no) fresh stems to tie-in, then that gnarled old stem will have to be left (unless it is dead of course). Ideally, strong green shoots can annually replace a few of the older stems. Tie them in with twine or a soft plastic tie (not plastic-coated wire) and avoid tying them too tightly – leave breathing space for the stem to grow. Aim to space the stems an even distance apart. If you have the space to fan out the branches, this will encourage lateral shoots along the length, on which the flowers will develop.
If the rose is on a pillar or obelisk, spiral the stems around, again keeping a regular gap between them. It is wise to tie-in promising young stems in late summer while they are pliable. They soon mature and may break if bent over later. The snap of a promising shoot on a still day may lead to bad language.
Shrub roses are best pruned in winter or early spring. Modern shrub roses, such as David Austin varieties, are relatively easy to prune. Remove a half to two-thirds of the stems, taking out inwardly wandering and damaged branches. Prune to an outward facing bud so that the bush has an open centre in which air can circulate and limit the build-up of fungal spores that cause black spot. Old Garden roses need a lighter touch. They are often the rose that “came with the garden” whose name is forgotten. These often flower on older wood, so need pruning more sensitively, not cut hard back.
A good job to do after pruning is to mulch. Garden compost or well-rotted manure will provide nutrients for hungry roses, as well as preventing the soil from drying out. Rose fertilizer granules are easy to apply in early spring, and a repeat sprinkling around midsummer will boost a second flush of flowers (for repeat-flowerers).
Personally, I feel uneasy spraying chemicals to treat greenfly and blackfly – I suppose you could call it my bugbear. Watching roses for just 5 minutes will reveal a community of tiny insects and predators that would have been obliterated by my trigger finger, had I chosen to spray. In the news again this week is a report about the decline, by a third, of native bee and hoverfly species. Spraying early in the morning, or late evening, when bees and hoverflies are less active will help to reduce harm to these pollinators and predators.
Spraying for black spot is problematic too, as chemicals have to be varied to achieve any beneficial effect. The fungus builds up a natural resistance to the spray if only one formulation is used, as it is is an ever-evolving organism. For this reason, new roses that a few years ago were labelled ‘disease resistant’ may gradually succumb to black spot. However, black spot isn’t the kiss of death, and good feeding and care of roses will leave them more able to shrug off these ailments.
Some of the best roses require little care. The Rugosa roses are bright green and healthy, and Roseraie de l’Hay has highly-scented rich crimson flowers and coral orange hips. Alba roses have lush green leaves and are powerfully scented. Or, one of our natives, Rosa canina, the Dog Rose, will bound carefree in a hedgerow.
Whichever roses you choose to grow, it is well worth putting in the time and energy required to ensure they thrive and are treated in the best way for their species.