Oh my gosh YES! It started for me last year and this year isn't as bad but I just can't seem to get it gone. I keep spraying my Bayer and keep wondering if I should use something different. Judy

In a battle with it now!! Nothing seems to work!

Immunox is much more effective than Bayer Advanced on PM. Avoid Immunox plus, which contains an insecticide.

Can you tell me where to buy that? Thanks!

Zack,

Many thanks for recommending Immunox. Off to the store for me to get it I go.

Dianne,

Just checked for Immunox (5-15-17):

Home Depot 16oz. $12.34

Lowe's 16 oz. $11.98h

Verify availability at your local Home Depot or Lowe's before you go.

Thanks again, Zack!

Moses

Is this related to the powdery mildew on honeysuckles? My orange honeysuckle looks like it has it . I hate to pass it along to all my roses !

As I recall HD and Lowe's sell different versions of Immunox. I prefer the fungicide only version that Home Depot sells.

Thanks Zack and Moses!

Looking for it today! Thanks everyone.

Zack,

Thanks for the clarification on Immunox. According to their web sites they both appear to sell the same 16 oz. size of Immunox without an insecticide included. Why do you prefer Immunox from Home Depot?

Moses

This Spring brought mildew to my garden as well. However, I find it far easier to get rid of -- if I'm really motivated to do so, since it'll go away when the weather changes -- than blackspot. The basic Cornell mixture cleans it right up. If you have a lot of roses, get an adjustable hose-end sprayer, and use that. If you want something a bit better, modify the mix -- use 1 part by volume of Dr. Bronner's liquid Castile soap, 2 parts neem oil, and 2 parts potassium bicarbonate. Put that in the hose-end sprayer, set it to 3 tablespoons per gallon, and spray until the foliage is dripping. For me, one spray usually gets rid of the white dusting of mildew, though affected foliage will remain distorted if it got that far. You can repeat it every couple of weeks to help keep blackspot at bay, but I'd avoid using it when daytime temperatures go above 85F. At that point, omit the neem oil. If that strength doesn't seem to be enough, try adjusting the setting on the sprayer gradually to increase the amount per gallon of water.

:-)

~Christopher

I have it bad on some roses, mostly McCartney rose and some others. At least I didn't get it on my Veilchenblau. One year I had it so bad on that rose, I lost the whole bloom.

Lilyfinch,

Powdery mildew is the same fungus that hits both roses and honeysuckle. Now, there are probably different strains of PM, just like the differing strains of black spot. The same strain may hit roses and honeysuckle, but may be more debilitating to one or the other.

I had a Goldflame Honeysuckle that came down with powdery mildew so quickly and thoroughly, it died to the roots almost overnight! I was caught off guard! It was magnificent, completely covering a 4' x 7' lattice with abundant blooms.

One interesting and amusing thing about my Goldflame Honeysuckle was that although it was not very fragrant, the bumblebees relished its nectar. Their proboscises were too short to access the nectar normally through the flower's long tube, so they routinely bit holes at the base of the tubes and easily sucked up the nectar through these holes.

Moses

I've never heard of the Cornell mixture!

Ever try Green Cure? I usually do not spray but did use Green Cure when Mister Lincoln had some PM a couple years ago...Used the cure rate and it seemed to stop it...

Here you go Prettypetals...

http://forums.gardenweb.com/discussions/2132507/cornell-formula

Green Cure is potassium bicarbonate with sticker-spreader.

:-)

~Christopher

I, or fellow rose folk friends, have experimented with many home made and organic sprays to no satisfaction. In fact, any oily/soapy spray has done more harm to the foliage than the disease itself in my garden.

I may try this formula for the honeysuckle. It just filled out so nicely but to be honest it's not my color and I can replace it with a climbing rose . I've never had it on my roses before and don't want to

Immunox plus has a broad spectrum insecticide that will kill off beneficial insects. This can lead to a huge spike in the spider mite population in my garden.

I hate powdery mildew. It is by far the most common disease for me, especially with fragrant roses grown in pots and as you say Moses, nothing seems to help.

Right now I'm very disappointed with the fact that most of my new roses for the season are already covered in mildew and look horrible with very poor stunted growth.

Do you think these roses will recover if I rip all the infected leaves and cut them back? (there were much more white powder on the leaves but I had wiped it off before taking the photos).

Henrik,

I am very sorry for the extent of powdery mildew you experience. Are your days quite a bit warmer, by a 15-20degree difference, than your nights? Has the weather been dry? These conditions favor powdery mildew in all its fury!

I knew a fellow who lightly, but thoroughly drenched his roses' foliage with just plain water frequently each day. The leaves rarely dried out sufficiently for the powdery mildew to spread. In fact it cleared up. Give this treatment a try. It worked for him.

My powdery mildew is waning now. Nights are warmer and rain is frequent enough. These conditions are not to powdery mildew's liking. Here I experience powdery mildew breakouts in spring and fall, not during the summer.

Do you have the spray Immunox or its equivalent in Sweden? Zack Lau endorses it.

Perhaps neem oil type sprays will also work.

The good bacterial spray manufactured by Bayer, sold in the USA under the label Serenade, may be helpful. It and neem oil are organic fungicides.

Black Spot takes center stage in the summer here. It is more deadly than powdery mildew, but strangely, easier to control, thank God.

Do you have much black spot in Sweden?

Moses

Yes Moses,
the weather has been mildew friendly lately but susceptible varieties seems to get
it in almost any weather here. I know part of the problem is growing them in
pots (I have no mildew on my roses in full ground yet, but they have only
recently started growing) and some of them are in unfavourable places (poor air circulation
or too windy). It’s also difficult to avoid water stress (to keep an even soil
moisture).

Black spot
(as well as other foliar diseases like rust) is also common here and with some
of my roses in pots it’s a bit like choosing between the lesser of two evils. I
rarely get any black spot on my container roses, but that’s only because I move
them under roof when it rains to keep the foliage dry. If I were to wet the
foliage like you suggest I would probably get all sorts of other diseases
instead and as much as I hate mildew I “prefer” it to the others.

We don’t
have Immunox here and I want to avoid using anything toxic (maybe there is
something similar available for professional use, but not for personal). I have
tried bicarbonate, baking soda, parafinol, sulphur, potassium phosphite and
milk with no luck. I have not actually tried neem oil yet, but it’s only
supposed to have “controlling” effect (not curative) like the others, right?

There is of
course a huge difference in how resistant different varieties are and an easy
solution would be to just get rid of susceptible varieties and grow only
resistant ones but I have a hard time giving up on them!

If your roses never get wet when it rains I'd suggest using Green Cure, which uses potassium bicarbonate.

I have used Green Cure for a couple years when I had about 350 roses, it used to be $9.99 per unit, much cheaper. It's too expensive now. It really works though.

After I use up Bayers, I'd try Immunox. Thanks Zack.