Roses may be the queen of flowers, but that role as monarchs didn’t protect them from taking a real beating this past winter.
The severe cold they endured caused severe dieback. Spring pruning and clean up, as always, is in order. If you don’t get to it for another couple of weeks, that will be fine. We cannot be sure that we are finished with cold weather for another month.
Clean up the ground around the roses removing winter debris and any mounds of winter mulch.
Assess your roses. These shrubs are clipped to reduce their height, remove old wood and stimulate new, productive growth.
Prune according to bush type. Hybrid tea roses are the most common. The objective of pruning is to thin and open up the plant to allow air circulation and to let sunlight in. Many gardeners wonder which canes to remove. The first decisions are easy. The first step is to cut back dead wood that is brown or gray and shriveled. Those who put a mound of protective mulch around the base last fall probably will have more living wood than those who didn’t. Remove the mulch and make the assessment.
Although it is perfectly acceptable to leave rose canes as tall as desired, winter kill may dictate the finished height.
Don’t despair just yet if your roses are looking pretty sorry. If it looks like all the canes are dead, just cut them back to about 12 inches tall and wait and see. They may send out growth from some living buds that you didn’t know were there.
The second step is to choose from three to six healthy upright canes arranged in a circular pattern. I have found that it helps to knock off any old leaves that remain on the plant from last year so you can see the canes better. Choose the best canes and cut the rest back to the crown of the plant.
Trim off the “candelabra” (the branched portion of the plant) and any damaged wood from the top of the remaining canes. Winter damage will dictate the proper height. If the roses haven’t died back too badly, prune the bushes to the height you choose. They do not have to be 18 inches tall to start the season. In fact, taller is generally better. Additional leaves help provide nutrients to strengthen the roots. Bushes will produce more roses if they are taller. Bring them up to waist height and enjoy their smell as you walk by.
Encourage outward growth and leave the center more open by making the cuts above an outward facing bud. Don’t leave too many canes.
Most roses are grafted to sturdy rootstock. Keep only those shoots that come from above the graft union. Shoots that come from below that union will be rootstock shoots.
Many roses are grafted to Dr. Huey rootstocks. Shoots that grow from this rootstock will be Dr. Huey roses. They will produce a spring flush of off-red flowers and then don’t bloom any more that season.
Many shrub and old-fashioned roses grow on their own rootstocks so all shoots will bear the same flowers.
Grandiflora roses are pruned in a similar fashion, except they are cut 3 to 4 feet high, again depending on the condition of the canes. If they need to be cut lower, so be it.
Florabundas bloom only once each year, so leave enough wood for good flower production this season. The flowers bloom on year-old wood.
Prune climbers carefully for good flower production. Prune sparingly by removing weak or dead wood at the base and cutting flowering laterals (side branches) to 6 inches or less.
When you are pretty confident of the weather, apply a complete fertilizer to boost blooming power and add additional high nitrogen fertilizer every 4 to 6 weeks throughout the growing season. Next, spread a layer of a couple of inches of bark, wood chips, sawdust or compost over the ground around the plants. Mulching roses will pay big dividends in healthy, attractive plants this summer.
Weeds are a problem in any garden. A layer of mulch will keep weeds down and eliminate the need for herbicides except on the most persistent perennial weeds.
Base the need for insect controls on how the plants have fared in previous years. Insect problems in the early spring are usually limited to aphids. If ladybugs are moving up and down the stalks on warm days, no control is needed. Otherwise, a dormant oil or insecticidal soap spray as the leaves unfold prevents these sucking bandits and spider mites from feeding on your prize plants. Controls for other insects can usually be delayed until a problem starts to develop.
We are lucky to live in this climate because roses have so few pest problems here. We seldom need to deal with black spot and other fungal diseases that decimate these plants in other areas.
The only disease we generally have a serious problem with is powdery mildew. Prune roses and surrounding plants to increase air circulation. Control of this disease is very seldom required. If treatment is necessary, organic controls include sulfur and baking soda. Preventative chemical sprays include Funginex by Ortho and Halt by Fertilome.