Seasonal Tips - Rose Care

Preparations for Winter

You should have stopped watering your roses in late November (the warmth this year should have had you continue tending them), as you want them to prepare to toughen up for winter. Watering encourages growth that will subject the plant to freezes when it will hurt the most – on new growth. In the same vein, you should not fertilize established roses in the fall.

Canes that have green leaves on them can be left alone. Wait to cut canes until there are no more leaves on the cane. Cut bare canes to about 18”, or short enough to fit under the cones you will use to protect the bush throughout the winter. Cut the trimmed canes into small pieces and dispose of them.

After the ground freezes, cover rose bushes with either 12” high mounds of soil, or rose cones. Another option is to place cages of chicken wire around the trimmed bushes (18” high and wide) and fill these with leaves.

You should not do any more pruning – unless you have canes that are damaged by harsh winter weather.

Remember to keep track of your rose care in your gardening journal. This will become invaluable to you as the years progress and your garden matures.

 Rose Diseases

Rose Black Spot, a common disease on roses, overwinters on fallen leaves. Remove all fallen leaves and other debris from around rose bushes. The signs of Black Spot disease are black spots with yellow edges on the leaves. As the disease progresses the yellow areas spread, leaves fall off prematurely and stems die back from the tip. Since it overwinters in infected leaves and stems, and can be difficult to control, the best solution is to trim off all infected stems and canes, and remove them completely from your property. Black Spot typically isn’t clearly visible until mid-summer (usually in July) and the severity depends on the variety of rose – some are resistant while others seem to invite Black Spot like it’s a favorite party guest. Warm, wet weather can also encourage Black Spot.  You can also spray for this; be sure that whatever you use contains myclobutanil, and that you spray when leaf buds are opening, and then again a week later. Spray again when spots first appear, and then every two weeks to maintain control.

 Rose Mildew is another widespread disease of roses. It’s a form of powdery mildew that develops on leaves, buds and shoots. Affected leaves curl and may fall off prematurely, diseased buds may not open properly or at all. This disease is encouraged by closed-in conditions (typically the cause of all powdery mildews) that discourage the free movement of air. Other conditions that support this disease are dryness at the roots of the rose bushes, poor feedings (remember you should fertilize your roses during growing season!) and hot days followed by cold nights. Be sure there is adequate space between rose bushes and walls. To control, cut off and dispose of infected shoots. Use a balanced fertilizer that isn’t nitrogen-rich (such as 10-10-10, or 15-30-15). If you chose to spray, be sure what you use contains myclobutanil or carbendazim. Begin spraying when the first spots are seen, and every two weeks thereafter.

 Spring Care

 Pruning

Prune your roses in the spring to remove weak or dead stems. Follow these steps to ensure proper pruning.

1. Select two or three strong canes, cutting them back to side buds that point away from the center of the plant.
2. Cut back to a “5 leaf” – a small stem that has 5 leaves or leaflets, near the middle of the stem. Try to leave at least two “5 leaves” on the remaining stem.
3. Make your cut about a quarter inch above the “5 leaves” stem. (If you have trouble with cane borers, dab a little wood glue on the end of the stem to seal it.)

 Watering and Fertilizing

You’ve heard me ramble on and on about mulch – here I go again. A good layer of mulch not only helps reduce the weeds and keeps soil from compacting (thereby ensuring there’s sufficient air in the soil for your plants to be able to grow and absorb nutrients), it also keeps your precious water from evaporating, and reduces the chances that heavy rains will splash water up onto the plant, which can spread diseases. Your roses need about one inch of water per week. Remember, when you’re doing the water (when Mother Nature isn’t doing it for you) to water the plant, not the leaves – keep the water at the base of the plant. This is most easily done with a watering wand or soaker hose.

 Fertilize your roses once a month from spring until midsummer with a balanced fertilizer (such as 10-10-10). You can use either pelleted or water-soluble fertilizer, just be sure to follow the instructions on the label, and to stop fertilizing after August 1.