Some of my bands I received from RVR have mildew, Is ok to spray them or what should I do?
Personally, I would not spray them. If your weather has been anything like mine (Encino, Zone 10), it's HOT and DRY (94 F with 7% humidity today!). Both of which discourage mildew, unless the plants are severely dried out when you can force most roses (and many other plants) to mildew. Just keep them watered and let it clear up by itself. With the drop in humidity and increase in temps, sprays can burn the plants. A bit of mildew this time of year is expected, but it's soon going to go away because of the rapidly upcoming natural change in the weather. Kim
What type of mildew? I would not spray babies for powdery, I would place in good circulation, nice dappled sun, etc. And what spray? Downey is another matter. I believe there are non toxics for use on them.
Some roses mildew as immature plants, and then outgrow it. (Tea Roses are a good example of that.)
I would get them into a larger container, so they can grow some roots, and keep them well-watered, and washed-off.
You can also spritz the foliage with skim milk or a milk/water solution. If the cuttings are outdoors, you will need to repeat the milk treatment every couple of days until the mildew season ends.
Its not as hot & dry here, its been around 80 & dry, maybe 30%. I have been keeping them on the dry side (afraid I am going to rot them) maybe thats why they are full of mildew.?
Its powdery mildew, I would have used bayer disease control, its what I have.
They have been in 1 & 1.5 gal pots for 3 weeks now so I guess they aren't bands anymore. The roses affected are quietness, SDLM & my MrsBRC. I watered/washed them just now & wont keep them as dry as I was.
I wouldn't worry if my other roses looked like this, but these being so small has got me worried they could die.
This post was edited by thahalibut on Fri, Mar 15, 13 at 12:38
I second the milk and water treatment. Sometimes I add a tiny amount of baking soda. You can look up a recipe for organic powdery mildew cures- it's well known.
It works well for me.
Powdery mildew, which could easily be induced by keeping the plants too dry. Spray if it makes you feel better but be aware that sprays can easily scorch and burn foliage when plants experience water shortage, even from a temperature spike on a very hot day. I don't spray for mildew, even on seedlings or newly propagated plants. That light of an infection won't seriously damage the plants. Being fried by a heat spike or intense sun after being sprayed can outright kill them in this climate. As temperatures rise and humidity falls, the mildew will clear. Those conditions don't support that fungal growth, unless the plants are kept in unsuitable conditions (lack of air flow, cold pooling, too high humidity from lack of air flow or kept far to dry). Kim
Take Kim's advice. It's right on target.
I like the milk, etc., approach. This looks like a fairly minor case on a teenager without other issues. I have had babies with far less than this and they have been just fine.
I could not understand why they were mildewing, its not humid & I thought conditions were perfect. Never would have thought keeping them dry would cause mildew. I know better know. I am not going to spray anything & see how they do with more H2o.
If you don't want to try milk- just getting the leaves bathed each morning will probably help.
Mildew is caused by LOW daytime humidity and high nighttime humidity.
Anything you can do to keep your leaves wetter in the day without increasing overnight humidity helps. The leaves will be more able to do their good work without the crud!
Baby roses often mildew because they can't keep their foliage hydrated as well as an established rose--the hydration level affects the vulnerability to infection. Then the rose grows up and establishes and is able to ward off the infection.
I wonder if the milk works because it makes a bit of a coating on the leaves- possibly helping them keep water?
When I got bands showing some mildew, I'd soak them with water in a spray bottle, mixed with a teaspoon each of baking soda and dish soap per quart, just before sundown. Then I'd be sure to rinse them off early in the morning with water from the hose. The mildew was gone in a few days of repeating this, and none of the soapy baking soda residue was left on the foliage by the heat of the day to burn the leaves.
This post was edited by AquaEyes on Sat, Mar 16, 13 at 1:59
Perhaps. Milk contains fat, and perhaps the fat functions like the oil in a Cornell mixture, either coating the leaf or smothering the fungi?
Speaking of coatings, there has been anecdotal comments on anti-transpirants such as 'Cloud Cover' being beneficial for preventing powdery mildew on foliage--it has worked for me on the young plants--after they establish, no further need.