Hybrid teas require pruning each spring before the bushes leaf out in order to obtain the maximum number of blooms and the best quality. There are no hard and fast rules for pruning and no ruleof-thumb methods for all varieties.
Severe pruning ultimately weakens the plants and makes them shorter lived. The young shoot depends upon the food stored in the older growth until enough leaves have developed to support it. Therefore, the more wood left, the more plant food is available to the young shoots. Light pruning results in larger plants with more blooms, and therefore a better display.
The first step is to remove all dead wood. Then cut out the weak twiggy growths. These are usually found near the base growing towards the center of the bush and are not strong enough to produce flowering stems. Crossing canes should also be removed. This should leave five to six strong growths which may be shortened, according to their vigor, to give a uniform appearance to the plant. Make all cuts so that the top buds are directed outward and the bushes will not be crowded in the center.
Hybrid perpetuals are more vigorous than hybrid teas, and so more stems and longer growth should be left. Prune more lightly than for hybrid teas in order to obtain as many blooms as possible. Dwarf polyanthas require little pruning in spring except for the removal of winterkilled wood. Remove the old flower clusters from them in summer and fall.
Tree roses usually require rather severe pruning, otherwise the tops become too large for the stem. • After removing all dead wood, shorten the canes to 8-12 inches and shape the over-all structure. Prune as necessary during the flowering season to keep the head within bounds.
Hardy climbers should be pruned soon after bloom. This stimulates new cane growth and the development of laterals for the next year's flowers. Where the roses are trained over any support so high that one season's growth will not cover it, cut off some of the older shoots at the ground, but leave the newer ones. Shorten vigorous canes, so that laterals will develop and eventually cover the supporting structure. In the spring, remove all dead canes and weak branches.
Many large-flower climbers, especially the everblooming types, do not produce as much growth each year as the hardier climbers. Therefore, prune them less severely.
Shrub roses are most pleasing when allowed to develop their natural shape. Some thinning out of old canes may be advisable.
Removing suckers
The rootstocks on which roses are budded in the nursery often send up shoots (suckers) that may crowd out the named variety.
To get rid of them, trace these growths to their point of origin on the rootstock and pull them out. Cutting them at the soil surface will cause them to send out other suckers from below ground.
Providing Winter Protection
When roses have been grown in a vigorous, healthy condition, they are more likely to escape severe winter injury, since they can mature normally. If roses lose their leaves from disease or mineral deficiencies, new growth may be stimulated late in the season, so that the plants go into the winter in an immature condition and are more susceptible to cold.
Sometimes rose varieties that are hardy in one area may suffer severe damage in an area much farther south where the temperature is higher but fluctuates more throughout the winter.
Mound soil 8-10 inches high around the base of the plant soon after the first heavy frost, to protect hybrid teas, polyanthas, and hybrid polyanthas in areas where the temperature does not drop below zero. Stake and tie all canes that might be blown about and thereby loosen the root system.
Protection in addition to mounding is required in areas where the temperature regularly goes below zero. In the fall draw soil up around the base of the bushes to a height of several inches. After the ground is frozen, cover the bushes with white cedar brush or other twiggy branches. The snow collects among the brush, thus giving the plants good natural protection. It is also held there for a longer period than on bare ground. In spring this brush covering shades the ground and helps prevent the heaving which often causes root damage when the frost is coming out of the ground. Straw and leaves are harder to clean up in the spring, generally impart an untidy appearance to the garden, and provide good cover for mice which may do much damage.
Tree roses should be pulled over on one side and covered with several inches of soil in areas where the temperature reaches —10°F. This is done by digging under the roots on one side until the plants can be pulled over without breaking all root connections with the soil. In milder areas wrap the head of the plant in straw and cover with burlap.
Climbing roses usually benefit from protection in areas where the temperature drops below zero. Lay the canes on the ground, hold them down with wire pins or notched stakes, and cover with several inches of soil.
Controlling Insects and Diseases
One control plan for diseases such as black spot and mildew is as follows: In the spring before the buds leaf out, spray with lime- sulfur, 1 part by measure to 10 parts of water. If the buds have just opened, the strength should be 1 to 50. Another spray with 1-50 lime-sulfur may be given about 10 days later if necessary, but this application may discolor the foliage as well as wood and stonework. From the time the leaves appear, spray or dust regularly with one of the proprietary compounds sold for this purpose. Where black spot has defoliated the plants, remove the surface inch of
soil in the fall and replace it with fresh loam. If insects such as rose chafer and midge are troublesome, spray or dust with DDT.
No comments:
Post a Comment