Autumn in my rose garden is a beautiful time. The sunny days and cool, longer nights give the blooms more time to grow and develop so the flowers are larger and the colors are more intense. This is a time to enjoy the rose garden and begin to prepare for winter. Nature prepares the roses for survival by putting them into a dormant condition in response to cooler temperatures and shorter days and all you have to do is encourage this dormancy. As the plant goes into dormancy the cell walls thicken providing protection against damage by freezing temperatures. Damaged plants are more susceptible to pests and diseases that weaken the plants for the year to come so you want to do what you can to get the plants into dormancy.
Timing is the most important aspect of rose care at this time. There are 2 significant dates: the time of the first frost and the time of hard freezes (usually about a month or so after the first frost). Find out your first frost date and plan accordingly.
Most roses take about 5-6 weeks or a bloom cycle so about –6 weeks before the first frost in your area do the following:
1. Stop fertilizing. Fertilizer will stimulate growth but the new growth will not be mature enough to survive the winter and a damaged plant will result. (Remember, damaged bushes are more susceptible to diseases and pests.)
2. Stop deadheading (removing faded blooms). A rose plant’s role in life is to reproduce by producing seed. If you remove the seeds by cutting the flowers the plant will produce more flowers and not go into dormancy. If you don’t like the look of the dead petals just remove the petals leaving the “hips” (the enlarged area at the base of the petals that contains the seeds).
3. Have a soil test by your local extension office and add lime if needed (usually about a cup per bush). Scratch the lime into the soil surface being careful not to disturb the roots.
4. Get rid of all dead leaves and petals in the rose beds because they harbor fungal spores and the eggs and grubs of insect pests.
N.B. If you have a regular spray program continue it as it does not hurt the dormancy process and will protect the leaves and flowers from disfiguring damage.
After the second or third hard freeze (temperatures below 28 degrees F) the plants will have gone into dormancy and you can proceed.
1. For most roses, prune long canes that might be blown by the wind to about waist height. Minis should be pruned to knee-high height, old garden roses as little as possible.
2. Spray with a anti-desiccant spray such as Wilt Pruf or Cloud Cover to protect the canes from drying out.
3. Mound 10″-12″ mulch (half as much for minis) such as chopped leaves or pine needles around the base of each rose. These will feed the bushes in spring as well as protect them in winter.
If you live in a mild area you may not need to mulch especially if your roses are not grafted and are grown on their own root. ‘Own root” roses may die back entirely but will probably sprout in the spring and grow into good sized bushes.
With no rose chores to do you can plan for next year. Design new beds, get out the catalogues, and order by December (for spring delivery) so you can have more beautiful roses next year.
I’m always surprised that some Roses continue to flower well into the Autumn and the first frosts. They appear so flamboyant and summery but are obviously tougher than they look.
I am amazed that my roses are still blooming with none the worse for wear after two killing frosts and many cool nights. The worst problem has been the fungi that thrive in the cool moist conditions. Once winter settles in temperatures in the teens (rare here) will badly damage the canes of the China and Tea roses.