I got my first (full size) rose bush recently, we put it in a large pot. It looked good, until I noticed some powdery white stuff on the stems, it was at the top where the flowers were, and went down from there a few inches. My mom told me it's a fungus and to clip the flowers off. They were almost finished blooming so I did. Was that the right thing to do?? How can I prevent this fungus. I actually saw at the garden center I bought it from on the other roses there too.... (I could get a picture if it would help)
Sounds like mildew. Roses are prone to all sorts of fungus/virus,insect pests. If you do not mind chemicals then spray as per manufacturers instructions with something like Rose Clear or any other systemic fungicide. If not then try the old method of 1 part full cream milk to 9 parts water as a spray.
This sounds interesting. Well if it was mildew, getting rid of it by deadheading your roses is a surefire technique.--the rose heads are something you would normally remove anyway, for the plants benefit. Boy, wouldn't it have been nice to have seen a picture, though. I find it quite a coincidence that the "mildew" was only on the stems (did I read that right?). I didn't read that the "mildew" was on any leaves. Personally I find this odd. The mildew attacks that I have seen in my own garden have begun on the leaves and spread from one to another, sometimes involving the stems very slightly. The distribution (on the stems near the end where new growth and flowers are) reminds me of one thing immediately.--It is the textbook location of aphids, and there is a sort of aphid that resembles middew, that is to saw, white and powdery in appearance. It makes me wonder if it could have been that. I had an infestation of this on a plum tree this past summer for the first time ever. I suppose that it is academic now that you have removed the ends of your rose stems; however, to be sure I would re-check every stem, bud and leaf just to be sure all is gone. If there is any more, please take fotos. I am sorry that I can't recall the name of that aphid sort at the moment.
I remember having white mold like that on some of my roses after a particularly wet spell. I removed those stems and sprayed with Funginex. The problem did not re-occur.
I did see some aphids, (at least I'm pretty sure they were aphids) but they looked larger than the powdery substance....But, there's actually 3 blooms still left and since it's not raining today, I'll go out and check out the plant and take some pictures if I see any more of this. If there are aphids still on it, how can I get rid of those? Are those soap pesticides good for that? And can I treat fungus and aphids at the same time? Or maybe will the fungicide kill aphids too? Sorry about all the questions!
Aphids on Roses are normally either green or red. Grey ones are more oftenfound on Lupins or members of the Cabbage family. Either way fungicide will not kill insects (except by accident). Yes the modern horticultural soap sprays will kill aphids. You can buy combined fungicide and aphicides.
It might also be mealy bugs. They are white and look cottony and a common problem on roses. If you can; just cut the affected part off. If it is too low to cut try orange oil or watered down dish soap for bugs. 1 part milk with 10 parts water sprayed on the plant does wonders for various mildews.
Hate to disagree with anyone ,but soap made for human use is not to be recommended for spraying in the garden, it contains some quite nasty chemicals, better with proper horticultural soap.
It is absolutely mildew on the leaves. There are some commercially produced sprays especially for this disease; however, I would remove and burn the affected bits. I personally feel that one of the most important aspects of treating this disease is the thorough cleaning of the ground at the base of the rose, picking up every dead leaf, every petal ...in short all debris from your infected rose that's lying on the surface of the ground. This is so that the plant (and other plants in the area for that matter) won't become (re-)infected. Another thing...if I see correctly, it looks as though that lovely rose is situated in a corner... is that right? If so it could possible be a key reason that your rose has become infected. What I mean by this is that when in a corner, there is restricted air flow because of the two solid walls on two of the four sides. Roses do need good air flow artound the branches and leaves...it's one of the reasons that you prune. You need remove that head and leaves as well as spray that little gem as soon as you can. Just one more thought, why don't you ruffle carefully inspect the mulch after cleaning it's surface to to see if there is some of that mildew undser the upper layer. I once discovered a mildew source IN the mulch under one of my rose plants and had to remove the entire layer and replace it with new. You know, I now have three roses. One growing up against my little garden shed and the other two out in the elements, and the one that gets most bothered by pests of all sorts from mildew to aphids is the one next to the house...every time. Well, I've had enough and I am going to set it out in the open this year. I will place it at the end of the clematis rack and see if it fares any better there. Good luck with your rose...do not delay any longer in taking steps to correct this problem. NOTE: If you want to have some fun (and proove that it is nildew), there is something that you can do...if you have a simple microscope, like the ones folks buy for their children. --Simply scrape a litttle bit of the white stuff off the stems and leaves, put it on a slide, add a drop of calcium hyfroxide...wait about 20 minutes then go and have a look. The mycelial elements will be easily visible if it is indeed a fungus. They will appear elongated with a barely perceptable greenish tinge to the edges of the "branches", as I recall. This may sound a bit clinical, but it is definative proof and something interesting for your kids...and perhaps you as well.
As we don't get much RAIN here, there's not much worry in regards to powdery mildew or black spot occuring on roses (water mine with a drip irrigation system set at ground level). However, green aphids were a never ending problem til I discovered a time-released systemic/fertilizer that you just sprinkle around plants after all danger of frost is past. Name is Bayer 2-in-1 Systemic, is ment for roses and flowers ONLY as stated on the label. The systemic is absorbed by the roots, spreads throughout the rose bushes keeping them..literally..bug free throughout the growing season while the fertilizer involved (12-18-6)does wonders for big, beautiful blooms! Because of the systemic involved, I WOULD NOT recommend using petals of roses treated this way for "candying" and eating, but otherwise they are fine for drying to use in sachets/pot pourris or just enjoying in bouquets. The Bayer product can be found at most chain stores that sell a good line of gardening products. I have also used this on flowering house plants that tend to become infested with insects with great success..just follow manufacturers instructions.
I have maybe two old fashioned roses that bloom once in early spring that are susceptible to mildew and they are away from my main garden and I don't treat them because we have such wet springs. I let them flower once which is still a great showing and then they receed into the background. The weather dries and the plant continues to grow. Sometimes the battle of disease is not worth it if the plant is just so prone to the disease. I hate to say it, but maybe you should think of moving or replacing that particular rose with another that is less fussy.
I would say that yes you have powdery mildew. It is a very common fungus that roses get. Make sure that you put the rose in as much full sun as possible. Try spraying it with a fugiside to help prevent future mildew. There is no way to get rid of what is there unless you cut or take the leaves off that are infected. Hope this helps.
