Soil. Roses require good drainage, so just about any soil in North Carolina will require either physical or chemical amendments before planting. To provide good drainage it might be necessary to prepare a 'raised bed'. Extreme cases may require the addition of drainage tile to carry away excess water. Since roses are expected to last several years, extra time and effort in bed preparation can be justified. The soil should be tilled to a depth of 8 to 12 inches with lime added to adjust the pH up to the 5.5 or 6.0 range. Various forms of sulfur can be added to lower the pH of alkaline soils. Organic matter such as decayed sawdust, pine bark, compost or manure may be added to soils to improve the tilth.
Planting. For best results planting should be done in the early spring or in the fall. In the mountains (at elevations greater than 3500 feet) roses should normally be planted in the spring. If individual roses are to be planted, the hole should be large enough so roots can be spread out in the hole. A good plant will require a hole 12 inches deep and 18 inches wide. Broken roots should be pruned and the top portion cut back to 5 to 7 inches. Before putting soil back around the roots be sure roots are loose and not pot bound. The backfill should contain native soil and not just prepared media. Roots then will grow out into the native soil and provide a better moisture relationship. Plants should be mounded slightly higher than "grade level." The soil should be tamped down to eliminate any air pockets. Watering during planting will also aid in this step.
Mulch. As in any landscape planting, mulch will provide aid during stress periods. Holding moisture, discouraging weeds, and preventing soil crusting, are a few added benefits of a 3- to 4-inch layer of organic matter. Disease problems can be decreased if the mulch is replaced each spring.
Fertilization. Do not over-fertilize newly planted roses. Generally speaking, a commercial grade 10-10-10 or 8-8-8 fertilizer at the rate of 2- to 3-pounds per 100 square feet is adequate. This can be applied in two applications early in the growing season. The addition of cow manure as a supplement is also advised. When the buds begin to form, apply another application of 10-10-10 or equivalent at the rate of 1 to 2 pounds per 100 sq. ft. Repeat this application every 4 weeks or until mid August.
Watering. When rose plants don't get a weekly soaking by natural rainfall, supplemental irrigation will be necessary. Typical North Carolina summers require this extra irrigation. An excellent system would be the soaker hose. This provides moisture to the root system while keeping foliage dry. If an overhead system is used, a morning irrigation would be recommended as the foliage would have time to dry, and the possibilities of black spot or powdery mildew infections would be lessened.
Pruning. Pruning could be one of the most important and necessary steps in growing roses. Correct pruning will improve the overall shape, promote new, healthier growth, and eliminate dead, broken, or diseased canes. Most of the annual pruning in North Carolina should be done in the spring, just as the buds break dormancy. This could be late February on the Atlantic Coast or late April in the northern mountains. The most important thing is to watch for bud swelling. Pruning too early will put future growth at risk to frost, and pruning too late will result in a plant weakened by loss of sap.
Spring pruning also allows for removal of wood which was damaged by the winter. This is helpful in the overall shaping of the rose. The height of the plant can be controlled by pruning, and even after a severe pruning new canes will usually grow to the desired height.
Sharp pruning shears are necessary. Pruning cuts should be clean and at a slant. The wood should be removed about 1/4 inch above an outside bud. Be sure to cut a cane down to a point where the cross-section shows no sign of discoloration. When working with diseased plants, dip pruning shears in a 70 percent alcohol solution after each use to decrease spread of disease organisms. Tree roses are pruned primarily for shape, thus requiring severe pruning cuts. Climbers are pruned according to class. The spring-flowering ramblers are pruned immediately after blooming. The old wood is removed to stimulate new growth which will flower the next year. Many climbers are pruned to be kept within a basic boundary with the older canes pruned. Corrective pruning and pruning of diseased canes should be done as soon as necessary.
Care should be taken not to damage rose canes when flowers are removed. First year roses should be allowed to bloom and not be cut continuously. After the rose bush matures, the flowers can be cut regularly.
Return to Roses
Send comments, questions to WebManager at
webmail@ncsipm1.cropsci.ncsu.edu