Late summer to early fall: Apply a slow-release fertilizer with low nitrogen content such as bone meal to promote root growth and next year's blooms. Stop fertilizing 6 to 8 weeks before your average first frost date to prevent new growth from being damaged by frost.
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.
October will be the last time to fertilize your roses for the fall growing season. Use fertilizer that is especially formulated for roses. You can alternate with fish emulsion. A dose of iron, zinc, Epsom salts and SUPERthrive applied at the beginning of October will do wonders.
Here's one gardening task you shouldn't do in late August. The end of August is not the time to fertilize roses, hydrangeas, fruit trees or shrubs. Feeding plants at the end of the growing season can stimulate new growth that can be burned by an early frost.
Feeding Roses in Winter
To get big, beautiful blooms from your roses come spring, you need to feed them in January or February. If you live where it is still snowing, you will want to wait until after the last frost to prune and fertilize your roses.
Prune the plants down.
Prune roses down to their bare necessities so you have less to worry about surviving the winter. Keep the strongest canes and flowers intact before winterizing them. In general, try to trim your plants down to two to four feet in height. This will help new growth sprout in early spring.
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.
Nitrogen is great for getting leaves to grow, phosphorus strengthens and encourages buds and roots, and potassium helps keep the plant in tip-top health for winter. A good general fertilizer for your rose bushes is one with an NPK ratio of 1:0.8:1.8.
I personally suggest you to apply Fertilome Rose Food, Espoma Rose Food, or Mills Magic Rose Fertilizer. These are 3 high quality results proven formulas that will provide consistent nutrients as watering and rainfall carries through to the root system.
Miracle-Gro Water Soluble Rose Plant Food promotes beautiful blooms and lush foliage. It starts to work instantly for quick, beautiful results. Ideal for all types of roses. Easy to use with the Miracle-Gro Garden Feeder or your watering can.
Most modern varietals of rose will bloom continuously, meaning that they can have a number of bloom cycles over the course of a season, which is typically May through October, depending on the climate.
Coffee grinds improve the soil around roses by fertilizing and enriching it. Roses require a neutral to acidic soil, and adding coffee grinds will help move the soil pH from neutral to acidic. Adding organic material to the soil will also improve drainage and aeration of your soil, which will benefit your roses.
Fertilizing in the fall helps plants be hardier when the temperatures drop. We also recommend applying fertilizer in the late fall, toward the end of October or early November. This application will catalyze one last frenzy of root growth and really give your plants some staying power through the cold months.
When is the best time to fertilize a knockout rose? We recommend fertilizing during the second bloom cycle in early spring, before bud set.
Most granular organic fertilizers act more slowly than their chemical counterparts. This means gardeners who want to get their roses growing quickly might want to add a liquid variety in the spring to compensate until the granular food begins to kick in.
Miracle-Gro® Water Soluble Rose Plant Food feeds instantly to grow bigger, more beautiful roses compared to unfed plants. Use with the Miracle-Gro® Garden Feeder or any watering can, and feed every 1-2 weeks.
They are a fast-acting source for magnesium and sulfur. For soils on the alkaline side, the added sulfur is a benefit. Epsom salts, however, do not contain any of the three major components of most fertilizers—nitrogen, phosphorus or potassium—and therefore would not be a complete fertilizer for roses.
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.
Wait until the first frost is over to prune.
Pruning your rose bushes can promote new growth. If you trim them before the first frost, it could create new buds that will be killed when the first frost comes along. This can damage the plant and make it produce less flowers in the spring.
Trim longer stems right after the first frost in the fall.
Again, it depends on the specific rose variety you are growing and your climate. For the most part, you can prune away dead, damaged, and diseased stems any time of the year.
Simply keep the roses at the height, and in the shape, you prefer. When you cut back flowering stems, leave 2 or 3 buds on the summer growth. In the cold season, prune English roses by 1/3 to 2/3 of their height. Almost all roses will quickly grow back and recover if you make any mistakes.
Fall: After the first killing frost, trim longer stems to keep them from snapping in winter storms. Keep rose bushes from being top heavy to protect them from being uprooted in strong winds. Crossing branches that could be damaged by rubbing together should also be trimmed back.
Can I cut my rose bush to the ground? Yes, but it's not usually necessary. The only reason for cutting rose bushes to the ground is if all of the canes are either severely damaged or dead. It's better to follow the steps above to give them a heavy pruning, rather than just cutting them down to the ground.