Fungicide for Gray Mold?

[Stvrob]

http://ipm.ifas.ufl.edu/resources/su.../Gray_Mold.pdf

[b54red]

Two days ago when I was picking my bush beans I saw what looked just like Gray Mold on some of the leaves. I had never seen it on beans before but they have grown very thick and tall this year and are in a fairly shady portion of the garden. Checking my tomatoes this morning and what did I find but Gray Mold on my Grubs Mystery Green and a slight bit on a couple of others near the beans. I was going to spray with copper this afternoon but since I already had Gray Mold present I decided to use the bleach spray and then follow up with either copper or Daconil. Now I don't know whether to use the copper or the Daconil or to use both. How long should I wait between the two and which should I use first?

Bill

[b54red]

I'm finding the directions kind of iffy on the Copper Fungicide by Bonide. They say to use between .5 oz and 2 oz. That is a huge difference in dosage. I have never used copper before and have no idea what dose to use. I used the 1/2 ounce recommendation since it is very hot here right now and I don't know if it will have any adverse affects on the plants. If anyone has experience controlling Gray Mold with a copper fungicide I would appreciate any input you have. I am afraid that the dose I used will be too weak to work well.

After using the bleach spray on the tomatoes and beans I saw Gray Mold on some of my cucumber leaves and on more tomato plants. Looks like those cold nights last week really got this stuff going. If it wasn't so hot I would just go out and spray with the bleach solution for several days in a row and then follow up a few days later with another spray. It is a lot of work but it will stop the mold if done early enough in the infection.

Bill

[sfmathews]

Bill, I used this one:http://www.naturehills.com/natural-g...nt-concentrate last week. It too has a wide dosage suggestion. I used it at 1oz per gallon. So far no burnage. I need to spray again, as we've had rain 2 out of the past 5 days and more predicted this weekend. Based on what I've seen, the grey mold seems to have stopped creeping up the plants. I would like to up the dosage a bit, since the humidity has been really intense here the last 10 days.
Good luck!
Susan

[Dewayne mater]

Susan - how has the Copper fungicide been working for you. Found some mold this morning on a couple of plants and that likely means there is more. That also means time to spring into action or it will be too late. Sadly use of Exel lg and actinovate has not prevented mold and doesn't appear to have treated some early blight on a couple of plants either. This rainy, windy, warm, incredibly humid weather is greatly increasing the disease pressure in N. Tx!

Dewayne mater

[sfmathews]

Hi Dewayne,
The copper has been working much better than the Daconil for control of grey mold. I haven't seen hardly any EB since I first sprayed a week ago with the copper. It is water proof, which means less spraying, since Daconil washes off after every rain and we've been having alot of rain. I hate the humidity, but we do need the rain to fill the lakes before the extreme heat of summer gets here.

[b54red]

Originally Posted by Dewayne mater

Susan - how has the Copper fungicide been working for you. Found some mold this morning on a couple of plants and that likely means there is more. That also means time to spring into action or it will be too late. Sadly use of Exel lg and actinovate has not prevented mold and doesn't appear to have treated some early blight on a couple of plants either. This rainy, windy, warm, incredibly humid weather is greatly increasing the disease pressure in N. Tx!

Dewayne mater

Whatever you can see means there is at the very least 2 or 3 times that much Gray Mold. The easiest way to find out how much you have is to use the bleach spray. In two days every spot that had Gray Mold that is hit with the bleach spray will be dying or dead. I was surprised how much I had. I thought it was only a few leaves on two plants. Two days after the bleach spray I used the copper spray.

I was spraying my cucumbers, squash, tomatoes and peppers with Daconil weekly and almost all of them got some Gray Mold. I find Daconil effective for most foliage diseases but it doesn't seem to have the ability to prevent Gray Mold down here. I'm hoping the copper works better. If not I'll have to mix up some more bleach and hit them again. The one really good thing about the bleach spray is if you use it correctly you can spray it often with no ill effects. The bad thing about is it is very tough on sprayers and pumps and it has no preventative value.

Bill

[Dewayne mater]

Guess I'd better go bleach first then and get what there is killed, then worry about prevention. I'm waiting for the wind to calm down. Its been blowing steadily at 15-20 mph with much higher gusts for about 3 days now, 24/7. I don't think I want to spray anything under those conditions.

I bought some Copper fungicide and noticed it said nothing about botrytris or mold, only bacterial spec, early blight, late blight and one other. It did say it would work on botrytris on some other plant though, so that's a little weird that it would work to treat mold on one plant but not another!? It also said it is much more effective for a broad spectrum of problems when it is tank mixed with mancozeb. I'm looking for a local purveryor of mancozeb so I don't have to wait for an on line shipment. Susan have you seen that in DFW? I know H.D. doesn't carry it.

Dewayne.

[sfmathews]

I did see some at Roach's Feed and Seed in Garland when I bought the copper.. So maybe check with some feed stores out your way?

[Dewayne mater]

Found it at an Ace hardward, fyi. The Copper fungicide says it is particularly effective when tank mixed with Mancozeb. Both say to apply at a rate of 3-5 tsp per gallon. Wondering if a tank mix would be 1/2 that amount per product or both products at the recommended amounts? If I do the recommended amount per each, I would obviously go on the low end of the recommendation. Anyone done the tank mix thing or otherwise have a thought on amount of these two products to use when using both at once? Thanks.

Bill - How long after a bleach water spray do I wait to apply these fungicides? Do I have to wait until the bleach kills the affected leaves or can I wait say from morning until evening then spray the fungicides? Thanks.

Dewayne mater

[b54red]

Originally Posted by Dewayne mater

Found it at an Ace hardward, fyi. The Copper fungicide says it is particularly effective when tank mixed with Mancozeb. Both say to apply at a rate of 3-5 tsp per gallon. Wondering if a tank mix would be 1/2 that amount per product or both products at the recommended amounts? If I do the recommended amount per each, I would obviously go on the low end of the recommendation. Anyone done the tank mix thing or otherwise have a thought on amount of these two products to use when using both at once? Thanks.

Bill - How long after a bleach water spray do I wait to apply these fungicides? Do I have to wait until the bleach kills the affected leaves or can I wait say from morning until evening then spray the fungicides? Thanks.

Dewayne mater

All you have to do is wait for it to dry thoroughly. I usually wait several hours. Make sure if you use the bleach spray to be sure of the concentration of sodium hypochlorite. The new stuff has around 8% and the old has 6%. I'm still using the old formula and added 7 ounces to a gallon of water and sprayed when the sun was down making sure to hit all of the plant and the soil under it. It worked well with no burning of healthy plant growth. You can spray it even on a windy day but wear old clothes. The concentration isn't strong but it might fade colored clothes if it got on them. I like spraying it when it is windy because it dries almost instantly with no puddling on the leaves. I don't like spraying Daconil in the wind for fear of getting some in my eyes.

I may spray with the bleach again this afternoon if I see any diseases when I go out and do a little pruning this afternoon.

Bill

[Dewayne mater]

Thanks Bill! Found your other post saying your chemist friend recommended 6 oz per gallon in the new formula and plan to try that. Then in the morning, I'm gonna mix Copper and Mancozeb and see what kind of preventative action I can get.

D.M.

[Paradajz]

Originally Posted by Dewayne mater

Found it at an Ace hardward, fyi. The Copper fungicide says it is particularly effective when tank mixed with Mancozeb. Both say to apply at a rate of 3-5 tsp per gallon. Wondering if a tank mix would be 1/2 that amount per product or both products at the recommended amounts? If I do the recommended amount per each, I would obviously go on the low end of the recommendation. Anyone done the tank mix thing or otherwise have a thought on amount of these two products to use when using both at once? Thanks.

Bill - How long after a bleach water spray do I wait to apply these fungicides? Do I have to wait until the bleach kills the affected leaves or can I wait say from morning until evening then spray the fungicides? Thanks.

Dewayne mater

Mix it both at regular doses, just as you would if you used them one by one.

Within specific formulas of clear substance in the specific product you use ( usually it's 80% for mankozeb, but ranges from 30 to 60% with copper, also various kinds of copper formulas like oxysulfate, oxychloride, etc. ) you need to simply calculate:
1) 0.20% of clear substance in the final mixture for mankozeb ( it equals 0.25% of a product which has 80% of clear substance in it )
2) 0.15% up to 0.40% of copper, but this is very specific- depends on the particular copper formula, size of copper particles in the product, the way it's mixed, etc., so it's much easier just to follow the recommended dose.

just pay attention- flowering period of a plant makes it more sensitive to fito- toxicity of copper, high temps also, so one needs to really follow instructions there
also, copper oxychloride has shown slightly more effective results on B.C. than other formulas.

br,
ivan

EDIT:
and don't forget to leave the mixture in the tank for a couple of hours and shake it up a couple of times, it'll provide you with better copper effectivness.

[b54red]

Originally Posted by Dewayne mater

Thanks Bill! Found your other post saying your chemist friend recommended 6 oz per gallon in the new formula and plan to try that. Then in the morning, I'm gonna mix Copper and Mancozeb and see what kind of preventative action I can get.

D.M.

I am going to start with a milder spray than 6 ounces of the new bleach til I see how the plants react to it. My chemist friend got some leaf burn using the 6 ounce mix but he may have done it when the sun was on the plants I don't know. I only used 7 ounces of the regular strength when I sprayed this afternoon. That is what I used last time and it worked good on the Gray Mold. When it is wet or the diseases are overwhelming then I go with 8 oz. of the regular strength. I also use the stronger mix for Septoria because it is so hard to get rid of and the longer it stays on the plant the faster it spreads.

I think I would start with no more than 4 1/2 ounces of the new concentrated bleach for my first attempt with it then if it isn't strong enough go up a bit til you find the right mix.

Bill

[Dewayne mater]

Well the dye is cast! I sprayed at about 5 ounces per gallon before I say this post. We shall see the effects. I wanted to jump on it because we've had a cool front come through and the high is supposed to be 84 today and low of 60 tonight. Tonight, I'll try the copper manzoceb mix and hope the relative coolness helps with that too. Thanks for those tips Ivan!

Its really a shame that this is happening now because I've got decent fruit set and tremendous flowering (Texas tomato food has to be at least partly responsible for that, thank you!), so I hate putting out harsh sprays. Still, I think I have no choice but to kill some leaves in an effort to get in front of the disease and keep the plants going longer. I'll report back on the phytotoxicity of bleach and the copper spray when the fall out is more evident. Thanks all for the input!

D.M.