I'm afraid there might be a misunderstanding. If you remove anything, it's LEAVES only, never ANY of the cane or stems (unless they show signs of infection), and it's just as important to keep the already fallen leaves picked up and removed as it is to take them from the plant. I know New Dawn is a thorny monster, but you need to hand pick leaves OR I've found it's easier to place a piece of plastic under the rose, shake the canes, and the leaves that NEED to come off WILL come off, and you can pick them up all at once with the plastic.

I don't know what your average temps are, but blackspot doesn't spread and grow much once the summer highs reach the mid 80's and stay there. It spreads best (worst?!) around 65-70F, but is active up to 80F or so, and needs to be damp for 6-8 hours in order to grow; and BS spores are killed above 90F.

If you are open to spraying, there are many options from almost organic (sulphur sprays) to the newer systemics which are absorbed into the plant and can cure as well as prevent BS. However, don't use any combo products that include insecticide, as many of these use the neo-nicotinids that are killing the honey bees.

John

I was going to spray today cos some of my plants shows BS. But we have above 100 during the day. Does it means that I shouldn't spray?

I personally wouldn't spray that hot, try early morning or early evening. I say early evening because i want it to dry well before night time. Seil you gave the perfect advice. I rarely romove leaves only because I don't have that kind of time with all the other yard work needed, but I do pluck the yellow occassionally just to make the bush look nicer. Nobody sees green leaves with black spot on them from a distance, but they will see the yellow. The rose is no longer gainining anything from a yellow leaf. I live in an area that is just prone to black spot, but I honestly do not spray very often. When I notice a rose is getting blackspot I sparay with Bayer then again in ten days and I find I don't have to spray again for awhile. Most sprays tell you every two weeks. I don't have that kind of time, nor do I enoy the job, lol!

I wouldn't worry about it much; just get rid of the yellow leaves. This rose is a tiny baby-planted out this spring, right, only a few months ago? It isn't established yet; it's root system is by no means developed,so it's not at all strange that the plant has some health issues. I bet that already next yer it will be healthier! but don't prune it at all. If it tries to bloom, it could be helpful to pinch off the buds,so it doesn't have to use energy on flowering and can dedicate itself to establishing roots.

What bart said. Baby roses frequently "grow out" of getting BS. Leave any green leaves, no matter what they look like. Let it grow some roots. Water it. New Dawn is a tremendously healthy, heat hardy plant here - it just needs some time to settle in and start growing.

Jackie

I am surprised to hear that New Dawn has blackspot. Are you sure that someone did not spray it with oven cleaner? :<)

i.e. I wonder if your obtained a mislabeled plant.

http://www.helpmefind.com/rose/l.php?l=2.4460

I always remove my leaves at the sign of blackspot even if green. I always worry that when water splash on it, it spreads to the other leaves. Did I do it wrong? I usually do it on plants which have lots of leaves. I like to pick them off near the middle and bottom area for more circulation as well.

You don't need to spray New Dawn unless you are doing it for cosmetic reasons. New Dawn is such a vigorous grower that it will survive some fungal disease. I would follow Seil's advice about not removing green leaves on a small plant. In Florida, New Dawn gets cercospora spots like crazy in the summer. In the spring and fall in Florida, New Dawn looks great and blooms like crazy, in the summer, only occasional bloom and it looks terrible due to all the spot.

Hi Henry, I think cercospora is often confused with blackspot. It seems like many of the roses that are resistant to blackspot are susceptible to cercospora, drift roses, the fairy, some of the knockout to name a few. It's quite a problem here in Florida.

I don't put anything on my roses if the temperature is 80 degrees or over. Make sure to water deeply before any pesticide application READ THE LABEL always