Most roses need pruning in early September to look their best this fall. September means it's time to turn off the water sprinklers, plant cool-season fall vegetables, and prune your roses for a showy fall bloom. Mark it on your calendar. Prune roses around Valentine's Day and Labor Day each year.
Last Day To Spray Off Roses With Water – Sept.
14. Lightly Trim Your Roses: After a summer of intense heat, all rose plants need a light trimming to set the stage for spectacular November blooms. This IS NOT the heavy pruning of plants that you perform in late January. First, cut out all dead canes from the summer.
Prune to remove dead or diseased growth at any time, though it is best to avoid major pruning from late summer through early winter, as the shrubs will be starting to go dormant. Deadhead as the flowers fade to keep shrubs blooming longer.
The first pruning, done in late January or early February, prepares rose bushes for the late-spring to early summer blooming. The second pruning is done in late August to early September and ensures shapely bushes with lots of flowers in the fall blooming season.
Summer: Dead flowers can be cut back at any time in summer. Carl Bennett, longtime Rose Breeding Manager of David Austin Roses, says that during the flowering season, deadheading will encourage more blooms and maintain an attractive shrub.
The Danger of Summer Pruning
Losing too much sap will weaken the entire rose bush. In this weakened state, the plant has a decreased chance of successfully fighting off a disease. In addition, the number of flowers will decrease as the plant diverts its stored energy toward healing itself.
If you want to do any cutting of your roses in autumn, wait until after the first hard frost (temperature below 25 degrees Fahrenheit overnight). If you cut back before the first hard frost, it may send a signal to the roses to grow when they should be going dormant.
Rose bushes don't always recover from such a major renewal pruning, and they won't flower much the first year after you cut the down, Occasionally this type of pruning will trigger growth from below the graft – watch for fast, straight-up shoots that come from the ground, not the stems above the ground.
Trim your roses again in late summer
Since we have a longer flowering season in warmer climates, I also recommend another pruning in August. This will encourage a second, hearty bloom cycle in October. This pruning does not need to be as hard-core and meticulous.
The best season to prune trees is while they are dormant, or generally between November and March. This means waiting for them to lose their foliage and cease growth, but before forming buds. For fruit trees such as the apple tree, prune in late winter.
You stop fertilizing roses in mid-August to late September depending on your climate zone. Make sure to stop feeding 2 months before the first freeze. Roses use a lot of energy flowering all season long so they need a rest period. You never want to fertilize roses in the winter because this is their time of dormancy.
Stop deadheading hybrid tea, grandiflora, and floribunda roses in September. The spent flowers eventually develop into hips (fruits). The development of rose hips slows plant growth and helps prepare the roses for winter.
Avoid pruning roses in the fall. Because pruning spurs more growth, stop deadheading or cutting blooms for bouquets a few weeks before your area's first frost date. As the weather gets colder, your roses will begin to go dormant, moving their energy reserves into their roots to help them survive the winter.
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.
After several days of below freezing temperatures, create a mound of soil, compost, shredded leaves or evergreens 8 to 10 inches deep over the base of the plant. Mounding keeps the rose uniformly cold, which reduces the chance of damage caused by cycles of freeze and thaw.
For most other types of roses, the best time to prune them is in late winter or spring, right after your last frost date. You'll want to track your local weather forecast because late frosts can vary by weeks or even months from year to year.
In fall roses instinctively send their sap down into the roots so there is no danger of that. Deadheading interferes with that process and you run the risk of damaging the roses.
Some are called self-cleaning and will not need any pruning. David Austin Roses should not be pruned the same as Hybrid Tea, Grandiflora or Floribunda roses. To allow your roses to harden for winter, stop deadheading and fertilizing around October 1.
They should not be pruned hard during the intense heat of summer. The two major pruning opportunities are late January through early February and late August through early September.
You can manage the size of a rose bush to some degree during the summer when pruning off faded flowers (deadheading). Generally, we deadhead by cutting back to the first five-leaflet leaf below the faded flower or flower cluster.
When is the best time to fertilize a knockout rose? We recommend fertilizing during the second bloom cycle in early spring, before bud set.