This has been a bad year for my roses. We have not had much rain, we are on a village water alert because they are replacing the water lines so we have been restricted to not watering etc.
My problem is that most all my rose plants have black spots on the leafs and they fall off the plant leaving a bare branch. I keep the area cleaned up, I keep deadheading everyday but this is terrible.
Anyone know how to stop this without digging everything up and starting over with new soil etc.
The rose bushes are around 3 and 4 yrs old and were doing fine.
Thank You
I am sorry no pics but the leafs are green black spotted turning to yellow and then fall off.
ROSESBlack spot leafs
Some pictures would help, but it could be black spot which is a very common fungal problem with roses. The only thing that doesn't seem to fit is the lack of rain & water restrictions, since typically moist conditions would be more conducive to creating this problem. But maybe the dry weather has stressed the plant which would make it a little more susceptible to disease in general, and then if you've done things like (when you area allowed to water) watering in the evening when the leaves will stay wet for a long period of time that could have caused the fungus to get started.
If it is black spot, you're doing the right thing by cleaning up the area rather than letting diseased leaves lie around. Fungicides can also be used, but they are more effective as a preventative if you apply them before you start to see symptoms. Here's some info: http://www.bhg.com/gardening/flowers/roses/how-to-save-roses-from-black-spot/
The good news is that every year is a new year, so even if they look awful this year if you clean up the infected leaves and next year treat with a fungicide before the disease shows up then your roses can look fine again next year.
ecrane3, I have always read that black spot was caused by excess moisture too. I was really surprised to see it on my neighbor's roses this spring. I didn't even know we got it here, and our rainfall consisted of 8" this past year! Rust and mildew we get, but I had never seen black spot before. Maybe the stress from lack of rain + our marine layer? Mine didn't get it, but I do cut mine back and clean up in winter...they don't.
Black spot can definitely be encouraged by excess moisture but I don't think it's a requirement. I had some roses at my old house (~30 mi north of here but fairly similar climate, ever so slightly cooler in summer but typically no marine layer) and they got black spot to some degree every year. We get a bit more rain than you do but not during the time when the roses have leaves so I don't think that would make too much difference. Some cultivars are also more susceptible than others, so it could be your neighbor has varieties that are more susceptible than yours? Being stressed for some other reason could increase their susceptibility, but since we never get rain during the warmer months I wouldn't think that lack of rain would be a factor in CA unless your neighbors decided their water bill was too high last year and really cut back on watering this year. Marine layer brings humidity and since it keeps things cooler it would also slow evaporation of water droplets from the leaves which would also be more conducive to black spot & other fungal diseases, but unless you've had a lot more days of marine layer this year than you usually do I would think your neighbors would have had problems in previous years too.
It may have to do with climate. I noticed that a one gallon Glamis Castle I bought, and put in a pot, and could therefore water regularly, has no blackspot or mildew. I did not even treat it with a product like Bayer 3 in 1, because they caution you not to use it on potted roses. The thing is perfect. And it refuses to stop blooming despite the fact that we have broken 150 year records for days over 90. It is never without flowers, and is producung buds constantly. (Kudos to Chamblees, by the way.)
We are closing shortly on my old house, and GC there is blackspotted and has lost most of its leaves. The difference is uneven watering. I noticed the same thing about lilacs. If I keep them evenly watered (I love soaker hoses) they get little or no mildew. But that may be peculiar to the Midwest.
I think you're at least partly right about the watering. My neighbor lets things go from desert to bog, and back, and I've given up on reminding him.
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