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powdery mildew?

Posted by txmom North Texas (My Page) on
Sat, Sep 10, 05 at 21:35

I have been battling diseases!
Powdery mildew - I guess. Now I seem to have white spots that are sticky.
On the advice of a AVS, tried Lysol.
Still spreading.
On the advice of local plant store, tried a fungus spray.
Still spreading.
Decided to just eliminate all the infected plants and tossed away 15 plants before it spread to the others in the room....now have found another with a problem on leaves and on the stem. I have isolated her and started the fungus spray treatments...day one.
Advice?


Follow-Up Postings:

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RE: powdery mildew?

Have you tried cinnamon? It can be sprinkled or brushed on. Powdered sulfur (can be bought at drug stores) is supposed to be a good brush on treatment, but I've never tried it. How about neem oil? I did a neem oil spray on all of my plants recently when I noticed the beginnings of powdery mildew on a couple.

I've started putting a little cinnamon in my soil mix. I've sprinkled cinnamon on the top of soil before to control a different fungus, and decided to use this as a preventative. The places I buy ingredients for my soil mixes are a little suspect sometimes.

~Brambles


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RE: powdery mildew?

Just in case your powdery mildew is not what you think, have you looked closely at the white spots? Powdery mildew appears as a very fine "powder" on the plants. I guess I am concerned with an undiagnosed foliar mealy bug infestation. These also appear as white spots. If you dip a cotton swab or Q-tip (as we used to call them) in rubbing alcohol, touch the white spot with the tip, and if the white spot turns pinkish you have mealy bugs. They can appear on the stems, leaves, and axils of the plants and are devilsh to get rid of. They are very contagious and my best advice is to discard the plant, if indeed it is mealy bugs.

Just an alternate diagnosis, and I sincerly hope I'm wrong!!!

Elaine


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RE: powdery mildew?

Hi Txmom,

I have to agree with Elaine. When I hear white spots that are sticky I think mealy bugs. Powdery mildew is not sticky.
As Elaine said, mealy bugs are very contagious and you should separate your plant from the rest of the population immediately. It is your call whether you want to treat the thing. If it doesn't have any sentimental value I would toss it. It will cost you more to treat it than its monetary value.

If you do want to treat it, safer soap works very well on mealy bugs. I would spray it three times a week for four weeks. Be sure to spray the entire plant including under the leaves.

Good luck,

Larry


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RE: powdery mildew?

  • Posted by Korina 9b, Sunset 17 (My Page) on
    Mon, Sep 12, 05 at 12:45

If it is mealy bugs, spraying with rubbing alcohol will kill them too. The first time I sprayed for aphids I was petrified I'd kill my plant so I tried one leaf. It didn't even twitch, so I sprayed the whole plant. All it did was kill the aphids. You will have to keep an eagle eye out and spray repeatedly because you'll miss some and others will hatch from the soil. But I won my war, so you can too.

Good luck.

Korina

'Lots of planets have a North!' -the Doctor


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RE: powdery mildew?

What is safer soap and where can it be purchased.. is it sold under the name safer soap or other name? Same for marathon.. I have searched for them at Home Depot and some of the nurseries in this area.. and the people just look at me.. And try explaining to them about urea.. they could care less.. but I finally found a nursery that carried Peter's without the urea.. now to find fish emulsion.. HD is out of it and will not have it until next spring.

I don't have mites, but what do yall use to kill them.. and I mean all types of mites? I know Avid is recommended.. but that stuff is EXPENSIVE!!! So what is the next best thing or should I just peel a few more potatoes and buy some Avid?

I am trying to get all the ammunition I could need, just in case I get some of these visitors.

All the sites on the web are very vague as to how much to use and how to mix it.

Thanks
Tea


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RE: powdery mildew?

Tea,

John Cook of Cape Cod Violetry carries both Marathon and Avid. However, he is difficult to get a hold of as he and his wife travel quite a bit. His Ph # is 508-548-2798.

I like Neem Oil to spray occasionally as a preventative. I know some folks will use this once a month for "just in case" measure. It is effective somewhat against powdery mildew, too. I know it is available at Lowe's and probably other such stores. It is fairly good against thrips doing repetitive sprayings. The very best control for thrips is Conserve.

Kelthane used to be used for mites, but it was taken off the market at the end of last year(I think). Safer Soap and Neem Oil are available thru www.violetshowcase.com It may also be available at Lowe's but at this time of year many items are not replenished due to end of growing season.

I hope some of this helps. It's always good to be prepared!!!

Elaine


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RE: powdery mildew?

Hi,

Safer Soap or Neem oil will kill mealy bugs. A place where I buy my chemicals from is They Violet Showcase. They are a violet mail-order house that also sells supplies and pesticides. They have both Safer Soap and Neem oil. I will put the URL on the bottom. When you get into the web site go to supplies catalog.

Spray each plant three times a week for four weeks. The reason for this schedule is to kill parent insects before they lay eggs and newly hatched insects before they go through their cycle. Make sure you get under the leaves and into where the leaves meet the stem.

I hope this helps,

Larry

Here is a link that might be useful: The Violet Showcase


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RE: powdery mildew?

For a moment can we get back on topic -

Does any one have any advice about powdery mildew in a room that is 4 weeks into flower?
I have been spraying 3 times a week with a copper based garden fungicide and this seems to be keeping it under control - but it shows up in a different plant each time -
The outside atmosphere has been quite damp of late which makes it difficult to reduce humidity..
Has any one any experience of running a crop like this thru to maturity doing ones best to keep PM under control..

Any advice greatfully received..


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RE: powdery mildew?

I have never had mildew.. maybe it is because I have an air conditioner unit for the room and it keeps the air moving.. also I use a box fan at times along with the AC. Maybe you should try a de-humidifer. I actually use a humidifer at 40%. I have a meter that measures humidity in the room so I can watch and control it. The temperature is maintained at 70 - 72 degrees at all times.

Not sure what you set up might be, but the above works for me and with no mildew!!

Tea


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RE: powdery mildew?

  • Posted by Korina 9b, Sunset 17 (My Page) on
    Mon, Oct 24, 05 at 12:57

Air circulation is as important as humidity in controlling p.m.

I live in a very humid climate, so I got a small fan for my light stand. It works pretty well; p.m. is rare now. In that stand, at least.

Korina

PS I use Lysol when I do get it -- kills the flowers, but also the mildew.


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RE: powdery mildew?

Hi JJ,

Korina is right on. You are doing all the right things. I would definitely add some air circulation to the mix. I have a small fan blowing on all of my plant stands to move the air around my violets a little bit. It keeps the mildew away.

I hope this helps.

Larry


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RE: powdery mildew?

There are a whole lot of things for small P Mildew problems. Cinnaman is good, we used poudered sulfur.

Air circulation is also a good thing.

But if you have a nagging problem with PM... then Fungaway is the gold standard. A light spray will keep PM away for a long time.

Ardy


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RE: powdery mildew?

Any one have any experience with cleansing a room which has
had powdery mildew before another grow..

It has been suggested that running ozone in there for a couple of days should do the trick -

Any comments would be appreciated..


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RE: powdery mildew?

One radical treatment for PM is a fungicide Topas, the generic name penconazole. But it seems not to be available for indidividual growers in USA. It whacks PM for a year. It is available in Europe in small doses - 5ml - enough for 5 liters of spray.

Irina


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RE: powdery mildew?

Hi Jack,

There is a misconception that one can clean the air of powdery mildew using different filters and such. Powdery mildew spores are everywhere. Running an ozone machine is not going to get rid of powdery mildew in a room that is not completely sealed off from the rest of the world. They say that the air in the average home gets replaced several times a day. Powdery mildew will be coming in to any room from the outside faster than it could possibly be killed or filtered.

African violets do not get powdery mildew because there is an abundance of it in the air. Powdery mildew is an environmental problem. Plants get powdery mildew because they are stressed in some way. Bad watering habits, heat, cold and lack of circulating air are all things that can stress African violets. I find the latter to be the biggest culprit for me. That is why I have small fans blowing on my violets stands.

Once you get an infection it is important that you treat it. It hardly ever goes away by itself.

I hope this helps,

Larry


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RE: powdery mildew?

penconazole and Fungaway are both triazole fungacides...
both are very effective and available in smaller quantities. I used this chemical as a systemic (soil treatment) in a rose bush that had horrible PM problems...
one treatment was all I needed for the entire year.... as opposed to weekly sprayings otherwise.

Ardy


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RE: powdery mildew?

Ardy,
If you want to get rid of mildew on roses, mix 1 part milk and 3 parts water and spray your roses as well as most other outdoor plants including vegetable plants with mildew. It not only kills mildew and makes the leaves nice and shiny. Works better and is safer than chemicals.
Ron


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RE: powdery mildew?

Thanks for the sugeestion Ron..
----If you want to get rid of mildew on roses, mix 1 part milk and 3 parts water and spray your roses Works better and is safer than chemicals.

I do have a problme however...
my roses tend to grow...
meaning they constantly send out new foliage
Do I understand your post to mean that
if I spray the old foliage with this mix you suggest, it will also protect the new foliage....
Thx
Ardy


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RE: powdery mildew?

Ardy,
You have to spray old and new folage on your roses whenever you see mildew. Roses also like a lot of air circulation - not too close together and away from any thing that causes air to become a little stagnant - like against fences or buildings. Some are more prone to getting mildew. You may want to look for mildew resistant varieties.
Ron


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RE: powdery mildew?

Ron
---You have to spray old and new foliage on your roses whenever you see mildew.

You see, what I tried and suceeded to do is to give the roses on single application of a chemical that solved the problem for an entire season. I am happy to accomplish the same result in some other non-chemical way. And I understand if you or others will choose to avoid using chemicals for any reason you choose. But I do not agree that I should stop using chemicals and as a result I have to constantly spray my roses, or not grow certain roses I love despite their tendency to suffer disease.

-- Roses also like a lot of air circulation - not too close together and away from any thing that causes air to become a little stagnant - like against fences or buildings.

Again, I prefer not to uproot my roses that are planted near my house... a poor initial planting decision, or a small garden that leave few options

Thanks for your thoughts Ron
Ardy


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RE: powdery mildew?

You can use whatever method you like. Makes no difference to me.
Ron


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