Most modern roses, even some heirloom varieties, will bloom all summer if properly groomed. “Deadheading” refers to the process of removing old or spent flowers from the bush. Whether you’ve been cutting the flowers to enjoy indoors or have left them on the bush to beautify the garden, proper trimming ensures strong reblooming. By deadheading roses instead of allowing them to form seed hips, you’re signaling the plant to produce more flowers. It’s also a way to continually prune and shape the plant.
Rose leaves develop in sets of three, five, even seven or nine leaflets. Notice the five leaflet leaves; these are where you’ll want to prune. Cut 1/4″ above a five-leaflet leaf, leaving at least two sets of leaflets on the stem from which you’re cutting. Pick a leaf that faces outward to cut above and make the cut at an angle sloping downward toward the center of the bush. Also, be sure to cut stems back to wood strong enough to support a new rose — at least pencil-thick is a good guide. If stems are too small they will either “go blind” (won’t produce a bloom) or will be unable to support the bloom’s weight.
While most rose gardeners fertilize in the spring when growth begins, midsummer feeding sometimes gets overlooked. Roses are heavy feeders — it takes a lot of energy to produce all those large, magnificent blooms! Many different fertilizers do the job — you can choose from granular, liquid, organic or slow-release. While each formula has its advantages, keep in mind that roses prefer a fairly balanced fertilizer where the N-P-K (nitrogen, phosphorus, potassium) ratios are fairly even (i.e. 15-15-15 or 5-10-5). High-nitrogen fertilizers without enough phosphorus and potassium, such as lawn fertilizers, will produce lush green foliage while sacrificing blooms.
You can combine deadheading and fertilizing, since they should both be done about every 4-6 weeks. Hybrid tea and floribunda roses produce new blooms 5-6 weeks after deadheading, while miniatures and shrubs will recycle in about 4-5 weeks.
pH measures the acidity (or alkalinity) of your soil. It’s an important consideration because of its effect on fertilizer. If soil is overly acidic or alkaline, then nutrients might be “tied up” in the soil and won’t be available to the plant, no matter how much fertilizer you apply. Roses prefer slightly acidic soils (pH of 6.5-7.0). Since some fertilizers can acidify the soil and since some areas have alkaline water, it’s a good idea to check your soil pH and adjust accordingly by adding garden lime (dolomitic lime works well) if too acid, aluminum sulfate or acidifying fertilizer if too alkaline. Adding more organic matter (compost, peat moss, decomposed bark, etc.) to the soil also helps to stabilize the effects of low or high pH.
Roses like a good, deep soak to promote deep rooting and they will actually develop drought tolerance if established this way. Frequent light waterings promote shallow roots that will depend on frequent watering. Applying the water slowly with soaker hoses or drip irrigation allows the water to soak in rather than running off, keeps water off the foliage (wet leaves spread fungal diseases), and reduces the puddling that can cause clay soils to form a hard surface less permeable to water. Mulching helps by reducing evaporation, retaining moisture, and preventing the soil surface from caking. If you use overhead watering, do it in the morning so that the foliage will have plenty of time to dry off before nighttime. Roots need air as well as water, so don’t keep the soil continually soaked. Allow the top inch to dry off before watering again.
Fall & Winter Care Tips
Fertilize and deadhead for the last time.
October and November
Depending on where you live and how soon fall and winter come, you’ll want to start protecting your roses for the winter. Once you have had a few good frosts, leaves will start falling off the plants. Apply a dormant spray such as lime sulfur and/or spray oil. This will kill pests and fungal diseases that might try to winter on the plant or in the surrounding soil. It can also help nudge those final leaves off. Rake leaves from around your plants to prevent the spread of diseases.
December and January
In Zones 9-11, roses usually don’t go completely dormant, but it still is a good idea to rejuvenate them at this time. Remove all the old leaves, prune out weak, spindly or diseased canes at the base, remove any canes crossing through the center, then prune remaining canes back by one-third to one-half.
This is the time to prune your roses – killing freezes have passed and the roses are just starting to break dormancy (buds are swelling).
Water your roses if there is no rain or snow for more than two weeks, to keep roses healthy and prevent them from drying out. Be sure to remove the soil mound and any other protective covering when buds begin to swell in spring.