Having recently moved from Osoyoos, where magnificent roses seem to flourish, toally disease free, I am quite frustrated with my efforts here. Apart from carpet roses, which seem to have no problems, climbers, HT's etc. seem riddled with mildew and black-spot. Although very reluctant to use sprays, perhaps I will have to, in this case. Any suggestions for the best, disease-resistant varieties, and for ways to control the disease?
I used Safer's Defender Garden Fungicide for the first time this year on a ballerina rose on my balcony. This is the first year that I haven't had to cut all the leaves off by the end of August because of mildew. It even has some flowers on it now. Of course, this has been a dry year, so maybe that's why it's doing well, but I didn't even have to cut the leaves off when it was first infected with the mildew earlier in the year.
One of the climbers I have is "forth of July". This one is fairly disease resistant and has red/white strip, lemon scent flowers. I actually have it grown in part shade and does very well. I hope this will help.
Welcome to the coast! If you have plenty of space, rugosa shrub roses don't suffer from the usual rose diseases. Many are very scented, have good fall foliage colour and terrific rosehips. The major drawback is they bloom only once in a season. For other disease resistant varieties there are a couple of very useful books to consult -- they should be available at your local library. They are Christine Allen's Roses for the Pacific Northwest and The Rose Expert. To control black spot, always be sure to remove all fallen leaves and put them in the garbage, not the compost. Christine Allen mentions the standard treatments, and points out one organic experiment that has had some success, but the results aren't conclusive: combine 1 level tablespoon of baking soda with 4 liters of water and 1 tablespoon of horticultural oil. Also the Danish Rose Society has reported success with a spray consisting of equal parts of skim milk and water. But please note: black spot is almost impossible to eradicate completely. The standard organic treatment for powdery mildew is also 1 tablespoon of baking soda to 4 liters of water, and this is usually quite successful. The main cause of this disease is lack of adequate air circulation and for this reason wall trained roses tend to be more prone to it. Good luck!
Rugosa roses I live in the Nelson, and I grow Rugosa roses. They are great up here, and I can imagine they would do well in the Lower Mainland because they originate on the Japanese seaside. I like Hansa, FJ Grootendorst, Therese Bugnet and Blanc de Colbert (the late queen mother's favorite rose, I'm told). The Hansa needs lots of room. The Grootendorst would make a good hedge. I have found many of them will rebloom in the fall if I cut the hips off when they form in June. My father grew New Dawn and Paul Scarlet successfully in Richmond many years ago. They are both climbers. Linda
