Regional Growing Guide: Coastal and Tropical South
Hot, hazy and humid describes much of the year in this region, where roses commence their first peak of bloom by Mother's Day, then continue budding out and blooming through December. While most of the rain comes during winter and early spring, fierce afternoon thunderstorms, nor-easters and even hurricanes may blow through during summer months. The soil may be acidic or sandy: amending with lime helps balance the pH, while compost provides nutrients and improves drainage. The best roses are heat tolerant and resist black spot: new roses often offer improved repeat blooming as well.
Select a season: Spring Early Summer Late Summer Fall
Summer Rose Care
Just like summer houseguests, roses eat and drink with abandon this time of year, and it's up to you to give them what they want.
Happily Soaked
Roses need water several times a week to grow and continue to bloom in dry weather, but wet leaves contribute to fungal diseases. Solve this dilemma with soaker hoses laid right next to the base of the rose bushes. If it just 'never' rains this summer, rinse their leaves with a gentle stream from your garden hose once a week to wash the dust off. Whenever possible, do this leaf rinsing in time for the foliage to dry before nightfall. Although a granular rose fertilizer label may say to use it once a month, its ingredients may be used up in three weeks. If leaves pale or stems thin by then, use a soluble fertilizer during the last week of the month. Think of it as a snack between meals for those hungry guests.
What to Cut
The first rose pruning technique for summer is deadheading, the second is shaping, and the third (for use later) is cutting back. Cut stems of old flowers just above a five-lobed leaflet to encourage a healthier plant and reblooming when possible. As shrub roses bloom and grow during the season, trim them between bloom flushes to maintain their shape, and try rooting a few cuttings. It's not the ideal time, but it often works anyway. Deadhead hybrid tea roses as the flowers fade, or better yet, cut long stems for the vase. Cut just above a five-lobed leaflet that points toward the outside of the hybrid tea to maintain its form.
Reblooming Rewards
Reblooming roses are often the best choice in our region. Each bloom may not last long, depending on thunderstorms and heat, but the flushes on many seem to come sooner.
Keeping Beautiful Roses Disease-Free
Roses are a favorite in so many gardens. But let's face it, those gorgeous flowers are sometimes accompanied by various rose diseases and pests. Is there an alternative to regular pesticide applications to keep these beauties producing the blossoms we so covet? Definitley, but it takes starting with the right rose and just a little care throughout the season.
Resistant Varieties
The first practice of a good rose grower should be to grow disease-resistant roses. Chosing any of the our AARS winning roses is a perfect place to start. You can visit one of our accredited public rose gardens to see these roses in the garden environment and chose the one that will be perfect for your needs. This will start you on your way to selecting roses for your own garden.
Another way to find the right rose for your garden is to read the most recent literature and catalogs. Breeders are constantly working on developing resistant roses, and the varieties available are expanded every year. One tip: a rose with a particularly leathery, puckered leaf is usually more resistant to leaf problems than one with smooth leaves.
The most common rose diseases are black spot, rust, and powdery mildew. All are fungal diseases, spread by spores being washed or blown onto leaves and stems.
Learn to Recognize Diseases
Black spot starts as tiny black flecks that turn into larger circular black spots. Eventually the spots coalesce into large lesions and cause the leaf to yellow and fall off. The spots appear on leaves and stems, and spend the winter on fallen leaves and infected canes.
Powdery mildew appears first as very small blister-like areas on young leaves, causing them to pucker. As spores reproduce, the leaf and flower buds become covered with a gray-white powder.
Rust, as the name implies, appears as rust-colored spots on foliage.
Preventive Strategies
Research has shown that black spot spreads most readily when foliage is wet. Therefore, planting in full sun, pruning to keep the shrubs open to circulation, and watering only at ground level will help prevent infection.
Powdery mildew, however, is best prevented by wetting the leaves since it needs dry conditions to thrive. A strong water spray several times a week will help prevent infection. As a bonus, this also helps control pests such as aphids and spider mites.
Another preventive method for diseases is to remove all foliage on the plant and on the ground in late fall, and to prune the tips of the canes. Both pathogens overwinter in fallen tissue and in the leaf buds just below the flowers. Pruning and clean-up get rid of many overwintering spores. If the canes are badly infected, a rose can be pruned to 4 to 6 inches from the graft with no harm.