As I write, our spring rose season is coming to a close. Later flowering ramblers, the pale pink ‘Apple Blossom’, ‘Edna Walling’ with its abundant clusters of white flowers, and the single white ‘Longicuspis’ will almost bridge the gap and join the first spring flowers to the second flush of modern roses.
We now move into another year and new challenges ahead. Keep your plants healthy by watering regularly, a mulch of pea straw will help keep the soil damp and at an even temperature. This will encourage the plants to grow and flower. Quality flowers are rare when the weather is too hot, so now culture can take two directions. Either continue the watering through summer on a regular basis or ease irrigation towards the middle of January into the first week of February. I prefer to do this as it allows the plants to slow down before they are lightly pruned in the first week of February allowing about 52 days for the flush of autumn roses. Light pruning is a simple task. Shoots are cut to a growing eye or bud about three buds below the spent flower. It is unwise to light prune after the middle of February as this does not allow enough time for the plants to produce autumn flowers.
A generous feeding with ‘Sudden Impact’ should be given to follow this light cutting and of course plenty of water to set the growth pattern into action.
Don’t forget to tie the long canes of climbing roses that are produce in summer and autumn. To avoid wind damage, tie to a trellis or support so that they are vertical. The sap rises to the growing tip and creates length. These long canes are vital to the restructuring of the plant as they will be tied horizontally at pruning time, eventually producing flowers next spring.
In hot dry weather, mildew and black spot become less prevalent, but spider mite can be troublesome. The mites can be found on the underside of the leaves. In extreme cases small webs join across the ribs of the leaves and a burnt surface on the top of the leaf is evident. If the mites are not controlled, defoliation and stem burn can occur. The colonies of the mites can be discouraged by a moist environment. The use of a sprinkler wetting the underside of the leaves is beneficial and this should be done early in the day to allow the leaves to dry off before nightfall, thereby reducing the risk of mildew and black spot. But spraying with a miticide particularly on the underside of the leaves should provide suitable control. Two sprayings about two weeks apart should ensure success.
As autumn approaches the days rapidly become shorter and cooler. Roses to be planted in winter should be ordered from your nurseryman. Order early to avoid disappointment!
By Walter Duncan