Part 1: A How to…Caring for your Roses - Fertilizing and Pruning
The most frequent question that people seem to ask is “How do I care for my roses from season to season?” Roses are one of the most popular garden flowers grown on the face of the earth and one of the easiest to kill. With the abundance of information available on roses and rose care, there is still some mystery about their proper care and maintenance. For every different type of rose available, there is probably a gardener with a different approach to caring for roses. It is as much of an art as it is a science to growing beautiful roses, but the following information will give you some important basics to help demystify the process. This fact sheet will discuss fertilizing and pruning. Since there is a lot of information to take in this ‘How to’ will be broken up into 2 parts.
Fertilizing
Because roses are heavy feeders, a routine fertilization program is important for plant health and vigor. To provide the proper nutrients for your roses in the amounts needed for optimum growth, it is important to first test (before you plant) your soil to determine its pH, texture (i.e., clay loam, sandy loam), and existing mineral nutrient content before adding fertilizer.
Roses grow best in the pH range of 5.5 to 7.0. Soils testing below 5.5 will need an amendment of dolomitic lime, 7 to 8 pounds per 100 square feet, to raise the pH into the desired range. Powdered sulfur can be used to lower the pH, for soils with a pH between 7 and 7.5, add one pound of sulfur per 100 square feet; for a pH between 8 and 8.5, add two pounds of sulfur per 100 square feet; and for soil with a pH over 8.5, add three pounds of sulfur per 100 square feet.
Soil texture, which is the relative percentage of sand, silt and clay composing soil, will influence the amount and frequency of fertilizer application. Sandy loams, for instance, will require more frequent applications because they drain rapidly, leaching essential nutrients. They contain little clay (and possibly organic matter) that would normally hold nutrients.
OK sorry if that was a lot to take in…if you are not comfortable with using fertilizers you can also use organic matter (2-4 inches and worked into soil), such as humus, peat moss, manure or composted sewage sludge for an added source of slow release nutrients (which means you won’t have to apply as many times). Organic matter can also improve the soils drainage and nutrient holding capacity.
Pruning
An area of concern for many gardeners new to growing roses is pruning. Why do you have to prune roses? What kind of tools do you need? When is the best time to prune? How do you prune? Does it matter what type of rose it is?
Basically, pruning is done to improve the appearance of the plant, to remove dead or diseased wood, to let in sunlight and air to the center of the plant and to control the quantity and quality of the flowers produced. Deadheading, or the removal of spent blooms during the season, encourages more blooms (on continuous blooming varieties), improves the appearance of the plant, and removes potential harboring sites for disease organisms.
Prune rose bushes to a uniform height, between 12 and 24 inches; remove suckers below the soil line.
The tools essential for pruning roses are pruning shears, long handled lopping shears and a fine toothed curved saw. All should be sharp to produce clean cuts and to avoid tearing or crushing the stems. When buying pruning shears, look for the hook and blade type, which have two cutting edges like a pair of scissors. The anvil type pruners, with one cutting edge, will crush the stem. Long handled lopping shears are best used on thick canes or ones difficult to reach with pruning shears. A fine toothed curved saw is used for larger climbing roses.
In general, roses should be pruned just before growth begins in March or early April. The exceptions are old (heirloom) roses and some climbers that produce blooms on the previous year's wood. They should be pruned after they bloom.
Following a logical sequence of steps while pruning will help make the job seem less complicated; the first step is to remove any dead, diseased or damaged wood. Cut the stems one inch below darkened areas, making sure you are cutting back to green wood. Make the cut at a 45 degree angle about 1/4 inch above an outward facing bud. Inspect the pith (center of the stem). It should be white. If tan colored, continue pruning sections of the stem until the pith appears white.
The second step is to remove branches that grow toward the center of the plant. This opens up the plant for better air circulation and allows sunlight to penetrate the inner portion of the plant.
The third step is to locate crossing branches and remove the weakest one. Crossing branches may rub against each other, causing abrasions that may serve as openings for disease organisms to enter the plant. Remove sucker growth, which is growth coming from below the bud union. Sucker growth is from the root stock and is a different rose variety; if not removed, sucker growth will crowd out the desired variety.
Finally, prune to shape the plant. Hybrid teas, grandifloras and floribundas can be pruned 12 to 24 inches in height, leaving up to 9 to 12 large (1/2 inch diameter), healthy canes. Old, shrub and species roses should be pruned lightly, removing no more than 1/3 of the growth. Miniature roses need only minimal pruning.
Many rosarians add one extra step to their pruning routine. After pruning, water soluble, white glue (i.e., Elmer's) can be applied to the cut surfaces of the stems to prevent rose cane borers from entering.
Rambling Rose: Group 1
Ramblers in the first group are derived from Rosa wichuraiana, including the cultivars 'American Pillar,' 'Dorothy Perkins,' and 'Excelsa.' They flower on one year old shoots produced from the base of the plant. When planting new bare root plants, it is recommended to prune the canes to 9 to 15 inches. Train the vigorous new growth horizontally on a support. There will be no flowers the first season, but profuse flowering the next. Strong young basal shoots will develop, too. In late summer or early autumn cut the stems that flowered at their base and tie the new growth horizontally. A few old canes can be retained, if pruning all would leave the plant looking too sparse.
Rambling Rose: Group 2
Group 2 differs from Group 1 only in the position of the new canes. The new canes for Group 2 grow half way up the old canes, not at ground level. Like Group 1, flowers appear on one year old wood. The plant is pruned after flowering by removing old wood up to the new growth then securing the new growth horizontally to the support. Examples of cultivars in Group 2 are 'Alberic Barbier,' 'Albertine,' 'New Dawn,' 'Paul's Scarlet Climber' and 'Veilchenblau.'
Rambling Rose: Group 3
Included in this group are roses that are extremely vigorous, capable of growing 20 feet in one season. Examples are Rosa filipes 'Kiftsgate,' 'Francis E. Lester,' 'Wedding Day' and 'Paul's Himalayan Musk.' These roses are best used as a ground cover or to grow up into trees. Very little pruning is necessary, except when a plant begins to overwhelm a tree. Pruning can be done to reduce the size of the canes or whole branches can be removed at the base.
Alright I think that is enough to take in for one sitting. PLEASE we encourage any questions you may have on Part One of “How to…Care for your Roses.” Stay tuned for Part 2 which will cover Disease Control and Winter Protection
