We cultivated our rose bushes in the spring with thorough cleanup, tidy pruning, and just the right start of fertilizer. We sat back all Summer enjoying our reward of blooms. Now as the season begins to wind down in August, we’ll begin a few steps to ensure our bushes are ready for their winter rest.
Follow these steps and timetable to tuck your roses into bed for the winter in Central Washington.
- Apply the last measure of fertilizer by mid-August. Later fertilization encourages new growth in late September to early October which will be vulnerable to fall frosts.
- Use a general purpose fertilizer, low in Nitrogen, but higher in Potassium and Phosphorus. A good choice would be an 8-12-6 or a similar combination. You do not want high nitrogen to stimulate a lot of top growth. You can use a rose fertilizer, but most of those have a systemic insecticide added which you do not need. Also, they may be very slow release, still feeding the plants two months or more later, which the roses do not need. Think in terms of those that provide about 6 weeks feeding.
- Rate of Application: About 4 ounces per plant. This need not be measured out to each plant if you have groups of plants. Calculate total needs (e.g., 20 plants @ 4 oz. per plant = 80 oz.) and then use a broadcast spreader to apply.
Last “dead heading”
- By mid-Sept. In the greater Wenatchee area plants tend to bloom into October and beyond if the weather holds. But you want them to stop. You can still cut a rose here and there for a bouquet. But they need to stop producing new growth which the frost will kill.
To Prune or Not to Prune
That is an ongoing basic question. There are several options:
- In early November, prune the top third out of plants to reduce and eliminate snow damage if we receive an early, wet snow. Do the finish pruning in the spring while the roses are still dormant but the chances of a hard frost are behind us (about late February).
- Leave until spring. The drawback is that roses in our area do not like to give up their leaves in the Fall and are vulnerable to breakage if we receive about 4-6 inches of wet snow while the leaves are still on.
Mulch for Winter Protection
- Apply mulch in late October or early November, after pruning.
- There are several choices – even soil. You can use straw, dry leaves, and compost.
- Cover at least to above the graft, or if the plant is on its own roots to above the root crown. The root crown is the point at which the stems of the rose meet the roots.
- Be sure to remove the mulch very early in the spring – otherwise it becomes a breeding place for a variety of molds.
Fall (the latter part of October), after the plants are dormant, is a good time to move roses. If you have crowded plants, or simply want to re-arrange plants, this is an excellent time to do so.
Make sure your roses (and all of your plants) go into winter with the soil moist. Fall rains may do this for you. If not, water enough to keep the root zones from going dry.
Late Summer to early Fall and in the Spring are probably the only times during the year when you will go through your roses thoroughly. Most of the year you will visit them randomly, dead heading, cutting bouquets, etc. This makes fall an excellent time to make notes about the condition of plants, possible additions, removals, potential problems, possible companion plants to be added, etc. or anything else you may want to remember to do in the spring.