Preparing for Winter
When September comes and the temperature remains a three digit number with no relief from heat or drought in sight, it is difficult to accept that 20-degree freezes will soon swoop down on our roses unexpectedly. Make no mistake, though, they will. In the meantime, the gardener must prepare for that cold, wet, reality as he revels in the air conditioning. In Zone 5, the roses enjoyed their last fertilization of the season by August 15. As long as the heat is extreme, they are watered and sprayed for pests and diseases as if the calendarís date read June 15.
But maintenance must be modified when the temperature readings are normal for the fall season. If the autumn rains do not provide the minimum of one inch of water per week, then supplemental watering must continue. Foliar feeding may account for part of that moisture but every effort must be made not to encourage the emergence of new rose canes which will almost certainly not survive the winter. As the weeks pass, water is gradually restricted to harden off (toughen) the rose canes.
The formation of rose hips tells the plant that its growth cycle is complete so it can begin to shut down for the winter. Pruning and disbudding are stopped since both encourage new growth. Instead of deadheading the spent roses, they are allowed to form fruit (the rose hips) which can be a source of food for birds during the winter. In order to reduce the amount of debris left in the rose bed, it is a simple task to clasp the spent rose at its base, pull off the petals and deposit in the trash. The hips will then develop undisturbed. (A word of caution about rose hip ingestion by humans. Hips are a greater source of Vitamin C than orange juice and are valued in herbal medicine, but, unless the rose plants have been raised as edible fruits treated only with chemicals non-toxic to humans, do not eat them in any form.)
The goal of rose maintenance before winter sets in is to create a garden free of insects and diseases which may survive the winter if not eradicated before winterizing cover is in place.