Rose Pruning and Winter Care
In the Sacramento area the best time for pruning roses is from mid December through mid February. In my own garden I started pruning on Christmas eve and I continue until I finish. With some 600 rose bushes and a full time job and family, this chore will continue every weekend through January. In this area our roses are usually dormant at this time of the year, thus the best time to prune. Waiting too long into February risks the danger of the buds breaking dormancy. Failure to prune our roses may result in plants with twiggy growth that are unable to support large blooms.
Tommy Cairns, in his article entitled The Complete Guide To Rose Pruning (January, 1989, Bull. L. A. Rose Society) defined the word "prune" as "to lop or cut off the superfluous parts, branches, or shoots of (a plant) for better shaped or more fruitful growth; to shape or smooth by trimming; to cut off or cut out (as dead branches from a rosebush)." Cairns also listed three reasons for pruning. He said that in colder climates the removal of dead wood from winter kill may be the main pruning activity, but in warmer climates the emphasis is on shaping the rosebushes for the spring bloom. The second reason for pruning is to encourage new basal growth from the bud union which is usually regarded as strong evidence of good plant health and vigor. The third reason that Cairns mentioned is that the removal of old wood and damaged and/or diseased wood allows a recuperative process to take place for increased growth power.
EQUIPMENT NEEDED FOR PRUNING
The following list of tools is a must for proper pruning. These tools should be assembled prior to starting. Sharp tools are of prime importance for making clean cuts without frayed edges or damage to the bark. Be sure all tools are well sharpened before starting to prune.
Although not equipment, it is highly recommended to be current with your Tetanus shots and to have a first aid kit nearby.
1. A pair of sharp slicing type quality hand pruning shears. The brand preferred by most rosarians is Felco. A good pair of #2 Felco pruning shears costs $32-$50, but they seem to last for ever. There are some inexpensive shears made by Dorcy ($8) which do the job very well but they do not seem to last more than one season. Felco has several models of pruning shears (e.g. shears for lefthanders, shears with rotating handles, etc.). Shop around and look what is available before you buy.
2. A pair of long handled lopping shears to cut out thick canes. Corona makes several models. The 24-inch handle model is probably the best one to get. This particular model costs $20-$50, but again, shop around.
3. A fine tooth pruning saw to cut away large stubs and canes close to the bud union. Corona makes several models of folding pruning saws which cost $10-$20. I use a #60 Felco folding pruning saw which sells for about $16-$20.
4. A pair of thick leather gloves or nitrile-coated canvas gloves that are puncture proof for protecting your hands. A good pair of goatskin leather gloves costs between $12-$30 while the newer Garden Handy cotton gloves with the nitrile coating costs $9-$12. Both types of gloves are excellent for pruning roses. At the last ARS Rose Convention in Denver I bought a pair of elbow length Gauntlet Gloves for about $23 from Kimbrew-Walter Roses [Route 2, Box 172, Grand Saline, Texas 75140. Phone: (903) 829-2968]. So far they are the best pair of gloves I have ever bought as it protects my arms when I am pruning within the rose bushes.
GENERAL TIPS ON PRUNING
The following pruning tips apply to established rose bushes. These tips do not apply to new bareroot plants. Newly planted roses should be pruned very lightly just to remove dead, diseased, broken, or twiggy growth.
1. Cut away all dead and old (grayish) canes. Always cut to good healthy tissue which can be recognized by the smooth green bark on the outside of the cane and white pith in the center revealed after the cut is made. When pruning, make all cuts at a 45 degree angle, about 1/4 inch above a bud eye.
2. Cutting back the height of the plant is a matter of personal preference and whether you are plan to use the roses for garden display or for exhibition. For masses of color in the garden prune lightly (e.g., one-third to one-half of last year's growth. For exhibition blooms, prune moderately (e.g., ½ to 2/3 of last year's growth). Keep in mind that some roses are more vigorous than others. Those that are more vigorous can be pruned moderately while those that are not as vigorous or "don't like to be pruned" can be pruned lightly. Examples of roses that don't like to be pruned are Brandy, Pucker Up, Ruby Pendant, Keepsake, etc.
3. Whenever pruning, decide in which direction you wish the new growth. New growth always comes from the very top bud you cut to. Cut about one-quarter of an inch above the bud you choose. The direction of the new growth is determined by the direction the bud points.
4. Open up the center of the plant in order to improve air circulation. Cut away all branches that cross over the center of the bush. Good air circulation around and within the plants discourages fungal diseases like powdery mildew.
5. Cut away all small, twiggy growth which is unproductive and robs our bushes of much needed nourishment for healthy growth. Twiggy growth is defined as growth on stems with a thickness less than that of a pencil. This growth is unable to support large blooms in large bush roses.
6. Cut off all growth from beneath the bud union of commercially grown plants. This growth is commonly called SUCKER GROWTH. Plants grown from cuttings or from seeds DO NOT produce sucker growth. Sucker growth is uncontrolled growth in the form of fast growing canes from the understock of the commercially grown plant. If allowed to grow, the understock will eventually take over the whole plant and suppress the desired rose variety.
7. Cut or saw all stubs from the bud union to enable new cane growth (=basal canes) to come from the bud union. Some rosarians use a small wire brush to loosen and remove dead tissue and thus clean the bud union. Except for the removal of loose bark and old pruning stubs, I don't recommend using any type of brush around the bud union for it is very easy injure this area and thus open it for bacterial and fungal disease organisms such as bacterial crown gall and rose canker.
8. After pruning has been completed, remove any remaining foliage from the canes and clean up around the bushes and rose beds. Discard all rose foliage and prunings in the trash or add it to the compost pile. In my own garden I discard in the trash all prunings thicker than ½ inch in diameter. The rest of the prunings I remove them from the rose beds and I mow them down with a lawnmower. The mower sucks up the leaves and prunings and shreds them. When the mower bag is full, I empty the bag in a compost pile away from the rose beds. In the spring I use the rich compost from the compost piles in the various rose beds around the garden.
9. After completely cleaning the rose beds of all prunings apply a clean up spray. If the plants are completely dormant a dormant spray can be used as a clean up spray for overwintering insects, spider mites, and fungal diseases. Dormant sprays for disease control fall into two groups -- sulfur or copper based formulations. If you use a copper based spray, make sure that it contains at least 50% copper. If you use a sulfur based spray (such as lime sulfur), make sure that you wash your sprayer thoroughly and do not mix other pesticides with it, as there might be some incompatibility. For insects, dormant sprays are mainly made of fine oils such as Ortho's Volck Oil. Oils work on certain insects and mites such as scale insects, aphids, fruit-tree leafroller eggs, and twospotted mites. If you had problems with these pests, then go ahead and apply the Volck oil. Please read the labels on the dormant spray containers and follow the directions very carefully.
I personally use a combination dormant spray made up of fixed copper (Kocide or Microcoop) with Volck oil as a cleanup spray after winter pruning my garden. I use this combination dormant spray on all my fruit trees, berry vines, and roses. I prefer to use copper as a dormant spray because of its action on bacteria and on fungi, especially downy mildew.
Alternatives to "dormant sprays" are applications of some of the pesticides that are used throughout the year. Orthene is a systemic insecticide that can be used for the control of overwintering scale insects and aphids. Daconil is a general purpose fungicide which can be used as general clean-up spray. It controls powdery mildew, blackspot, rust, downy mildew, and other fungal diseases. Funginex (Triforine) can also be used however, it does not control downy mildew which can be common during the cold, damp winter months. Please read the label carefully when using any pesticides.
If the rose bushes are no longer dormant and the buds are swollen, your clean up spray can be a mixture of Orthene and Funginex, at the strength indicated on the container. Under no circumstances exceed the dosage recommended on the pesticide label even if you use this spray mixture in lieu of a dormant spray.
Note: Some rosarians recommend sealing the ends of pruned canes in order to prevent "cane borers". In the past I also recommended this practice but in the last few years I no longer recommend this practice. Instead, I recommend that efforts be made in keeping the aphids under control in the home garden. The two main "cane borers" that are common in most gardens thus far seen, are dependent on the aphids for food (directly or indirectly) for their larvae in the nesting burrows in the rose canes. Therefore if the aphids are under control, you get rid of the food source and the "cane borer" wasps go somewhere else where the food (aphids) are more pentiful.