Once they begin to grow, you can start fertilizing your roses. We fertilize our roses three times during the growing season in April, June and August with an organic fertilizer such as Rose Tone™. This regimine is supplemented with foliar feeds.
In July and August, feed at three- to four-week intervals. Make sure plants are watered before and after each feeding and be sure to dilute all fertilizers according to their label.
I recommend organics for summer rose feeding. There are lots to choose from: fish emulsion, blood meal, chicken manure, cottonseed meal, or kelp. Around Labor Day it will be time to begin preparing your roses for the fall bloom cycle.
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.
During the hot days of August, mulching the rose bed is very helpful. Try a 2 to 3 inch layer of compost, DRY grass clippings (fresh or green clippings remove nitrogen from the soil), or dry cow manure. Adding dry mulch discourages weeds and conserves water in the soil.
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.
Roses can be deadheaded throughout the growing season. For old roses, prune after they bloom in the late summer or fall. Generally, roses can be pruned in the early spring before the leaves appear as well.
Fertilize the perennial regularly throughout its growing season (about every two to four weeks depending on the type of fertilizer used). Stop feeding your roses in late summer when they begin preparing for winter dormancy.
Stop fertilizing six to eight weeks before the first average frost date in your area. The reason behind this is that you don't want the plant to produce a lot of soft new growth late in the summer that will be damaged by cold weather in the fall and 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.
Easy on the summer fertilizer
Excess fertilizer (especially nitrogen) can burn plants in dry weather, and the salts in them can actually make plants less able to weather drought. Except for plants in pots and baskets and maybe roses, mid-summer is often a time when you can put the fertilizer bags away.
Miracle-Gro Water Soluble Rose Plant Fertilizer helps produce big, healthy and colourful roses that are noticeably more attractive, vibrant and healthier than unfed plants. Instant feeding action feeds your roses quickly after application.
Many gardeners interpret the lower vigor and poor-quality flowers to mean that the roses need more fertilizer. Since heat is the issue, however, roses actually need less fertilizer in late June, July and early August.
August is an ideal time for gardeners to give their plants a boost into the later stages of growth. Many people who are just learning how to garden at home overlook the benefits of fertilizing their plants.
The Sin: Overfertilizing.
The common misconception is that more fertilizer=more blooms, but roses only need so much fertilizer, and adding too much synthetic fertilizer can kill natural soil bacteria and/or lead to salt burn, which can both harm your plant.
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.
Any heavy or moderate pruning of rose bushes is not advisable during the hot summer months.
As long as you consistently remove the faded blossoms, your rose will continue to bloom throughout the summer. Now, you may want to fertilize your roses after they blossom so that they always have ample nutrients and energy to stay beautiful.
Your plants are hungry.
Ideal for all types of roses. Easy to use with the Miracle-Gro Garden Feeder or your watering can. For best results, feed your plants every 7 to 14 days during the growing season.
Give your roses 1 to 2 inches of water each week in a single watering session from early spring through fall. Increase the frequency to every three or four days in hot and dry weather. Porous soils will also benefit from additional deep soakings.
Miracle-Gro Rose Food should be applied every 7-14 days during the growing season per the manufacturer.
As a rough guide, in extremely hot weather you should assume rose plants will need watering daily. On a standard summer day with decent heat, you will need to water every two or three days, and in warm dry weather you will only need to water about once a week.
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.
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.