Roses are challenging in South Florida unless you use the old so-called Florida Cracker roses which are shrubby and have flowers in clusters. Blackspot and powdery mildew are often problems as are spider mites and thrips in the dry season. Roses need full sun and watering every four to five days if there is no rain. Watering should be done in the morning only. If you are in a situation where you cannot control the irrigation, invest in a replacement half or three quarter head to throw water away from your roses. A soaker hose is good as water can slowly ooze out and not get the rose foliage wet. Pick off affected leaves and clean up any foliage on the ground that could harbor fungal spores. These spores can re-infest your plant. Try Polyantha or Floribunda types or the old-fashioned roses like Louis Philippe (red) or Pink Pet (pink) for minimal spraying. Hybrid teas usually require more work. The Cooperative Extension Service has bulletins on rose care.
A. Your roses have blackspot. They need an area that receives at least six hours of sun a day as well as good air circulation and drainage. Water them with soaker hoses only in the morning to minimize fungal leaf spot. Spray with Daconil or Funginex for control.
Q. My wild climbing rose is dropping leaves and has stopped blooming. What is wrong?
A. Your rose has powdery mildew. For control, spray with copper fungicide, following label directions. Repeat in ten days. Spray only in the morning before 10.
Q.My friend is having trouble with her rose bushes. She uses Funginex and Jobs spikes for fertilizer. Could her rose disease be copper leaf?
A. Funginex is a good all-purpose fungicide. Water in the morning only and use soaker hoses to reduce fungal problems. Fertilize with a granular rose fertilizer. The spikes concentrate the fertilizer, and you may burn the roots. There is no disease called copper leaf to my knowledge. You may be thinking of rust, which is more common in California and other drier climates.
Q. I have spider mites and thrips on my roses. What should I use?
A. Soapy water or Safer's Insecticidal Soap are good controls for these small insects. Systemics like Orthene also give good control. Orthinex combines fungicide and insecticide.
Q. We want to plant a rose tree in our community as a tribute to a friend named Rose. I have been to several nurseries and can not find one. Can you help me?
A. The majority of roses require weekly spraying and are too much work for the average residential community on common land. Most maintenance companies come through every two weeks and would not be bothered with rose tree maintenance. Rose trees are grafted on a high-stemmed understock that would also be very prone to blowing over. I would strongly advise against the rose tree concept. Instead, I suggest a shrub type rose that would not require spraying and would be a repeat bloomer. Most of the shrub type roses will get at least 5-6 feet in height over time and would make a nice memorial statement. Some of the better types include `Care-free Beauty,' `Carefree Wonder,' `Louis Philippe,' and `Old Blush'. Select a well-drained, open, sunny location. Plant a groundcover like liriope around the rose if it is going to be freestanding in a lawn area. The liriope will keep monofilament trimmers from girdling the rose.
Q. I have a lot of Jackson & Perkins roses that have been losing leaves, which I think has been caused by fungus. Our condominium association waters every other day around 3:30 a.m. and has reworked the irrigation system. The sprinklers used to go off at 6:30 a.m. Could this account for the yellowing I am seeing on roses and annuals?
A. Roses want full sun, good air circulation and good drainage. The timing of the sprinklers should not add to the fungal problem. Watering any time between 2 and 10 a.m. is OK. But the water is coming on too often. Once every four days should be fine for established landscapes. The Jackson & Perkins roses are probably grafted to Dr. Huey rootstock, which is susceptible to nematodes. The roses will last about three to four years in the landscape before they die out from nematodes. Fortuniana rootstock is the best for South Florida and can last 30 years or more. Make sure all your roses are grafted on Fortuniana, which resists nematodes. Paying more for these roses is worth it because of longevity.
Q. I would love to plant a `Blaze' red climbing rose here. Will the plant do well here? If not what do you suggest?
A. `Blaze' would have lots of blackspot problems here. Give the rose full sun, good drainage and good air circulation to minimize disease problems. Water in the morning only between 2-10 a.m. I would recommend `Don Juan' which is a red rose with fragrant larger red flowers and better disease resistance. Make sure it is grafted on Fortuniana rootstock.
Q. Can you recommend roses for containers?
A. Old-fashioned roses should do well in large pots and will be much easier than hybrid tea types. Miniature roses are also good.