Cleary's 3336F Is it safe for all orchids?
 

I just ordered some Cleary's 3336F Systemic Fungicide. I was wondering if anyone knows if it is safe to use on all orchids? Does anyone have experience good, or bad using it on particular orchid groups. Thanks.

I've never used Cleary's myself but Dr. Martin Mote's recommends it in his book 'Florida Orchid Growing'. Our local orchid supply store carries it for use on orchids and I've heard several growers talk about using it on orchids. It's one of the products that commercial growers use on orchids in South Florida also. I don't know if there are any orchids that are sensitive to it. I've always seen it as Cleary's 3336. I haven't seen the 'F' on the end. Is that a different product. What kind of fungus problems are you having?

---------- Post added at 08:29 AM ---------- Previous post was at 08:16 AM ----------

I just looked at the Cleary's web-site. The 'F' stands for flowable or liquid. They also have 'G' (granule) and 'WP' (wetable powder). On the web-site they say it's not recommended for Boston Fern, Sweedish Ivy or Easter Cactus.

I would love to know as well. I want some but it seems that they are only sold in larger quantity for commercial use.

Thanks for the info tucker85. I assumed the F was for Fungal :shock: I don't have a large problem, but some of my Cattleyas have recently developed some circular spots on their leaves. I looked on the St. Augustine site and it looks exactly like a fungal problem called Cercospora Leaf Spot. They recommend Cleary's but I am not sure what dosage or anything. And then there are the spots I seem to get on many but not all Oncidium and Milt types of orchids which I thought I could maybe prevent.

I just received the bottle today. NYC, I found it in a quart bottle on a few sites on the web and I ordered mine from the U.S. It's not cheap. It was $62.00 plus the shipping. It seems quite concentrated tho so would last a long time.

There are some precautions of not to eat anything treated with it so I am a bit concerned as my one cat does like to chew orchid leaves. My orchids are in the greenhouse where he is not allowed. I just bring them in when in bloom and put olive oil and cayenne on the leaf tips of the ones he is attracted to and this has worked to prevent the chewing.

I think I will only treat a few with the worse problem first and see how it goes. I haven't done a lot of checking the booklet yet but it looks like only .2 oz. per gallon for mixing it??

Silken, what kind of water do you use on your orchids? I accidentally discovered that orchids are susceptible to fungus when they don't get enough calcium and magnesium. Cal/mag are usually in municipal water supplies but if you use rain water or RO water, it would be important to use a fertilizer with cal/mag in it or a cal/mag supplement. Here's an article about the need for calcium in orchids.
http://www.staugorchidsociety.org/PD...ps-Calcium.pdf

Yeah, it is systemic so will stay in the plant for a long time.

Cats better stay away.

Southern Ag has the same product in wettable powder form and its considerably less expensive. You can use these products for preventative purposes once or twice a year.


-Zach

I switch between using rain water when I have it and tap water. I collect the rain water for things like the Phrags mostly because they don't like our city water. I don't think calcium shortage would be a problem for that reason. But I did buy a bottle of Cal/Mag. in Feb. after reading various comments here on OB. So I do add it to the water now and then. I feel that the Paphs especially maybe like it and they have never grown for me as well as I would like so I thought it might help.

I have only seen this spotting in the last year, so became a bit concerned and thought I better try and stop it.

---------- Post added at 12:11 PM ---------- Previous post was at 11:55 AM ----------

Thanks for the link. Very interesting article.

---------- Post added at 01:36 PM ---------- Previous post was at 12:11 PM ----------

I wonder if Ray has any thoughts on the use of Cleary's??

Thanks. Cleary's is listed as fungicide tho not bacterial. Although based on the St. Augustine site mine look like a fungal infection. I see a lot more posts and info for the dry form of Cleary's and mine is liquid. It sounds like about 1/2 tsp./gallon of water is what I need.

I think that 1/2 to 1 teaspoon is correct according to the label.

The Cleary 3336F label here (pages 6 & 7):
http://www.clearychemical.com/support/label/4172SL.pdf
states 12-16 fl. oz. per 100 gallons for foliar application or 8-16 fl. oz. per 100 gallon for soil drench application.

My dictionary says that a teaspoon is 1.33 fluid drams and that a fluid ounce is 8 fluid drams.

So converting the given application rates of 8 - 16 fl. oz. per 100 gallons to teaspoons per gallon we have:
8 - 16 fl. oz./100 gallon = 64 - 128 fl. dr./100 gallon
or 0.64 to 1.28 fl. dr. per gallon.
dividing fl. dr. by 1.33 to get to teaspoons we get:
1/2 to 1 teaspoon per gallon.

I dislike working in teaspoons so I multiply fluid ounces by 30 to get milliliters and then work in milliliters (a fluid ounce is actually 29.56 milliliters).

Thanks David for backing up what I was thinking. In the end, I took a well marked ounce shot glass and measured 10 1/2 teaspoonfuls to make one ounce so given the rate of 8 to 16 fl. oz. per 100 gallons I figured .1 to .16 oz. per gallon and .1 is 1/2 tsp so I might use a little more but no more than 1 tsp for sure. Maybe 3/4 tsp. My method wasn't quite as mathematical or scientific but worked out the same in the end so now I feel more confident that I am not over-dosing my chids. :) And I will use a proper mask and rubber gloves before applying. Not sure if it is necessary but...

I would also like to add something helpful by Mr Motes who just happens to be our speaker aug 1st :waving

Orchids need a hard drying out of the whole plant and roots on occasion. He says the purpose of this is to kill off bacterial and fungus that might be hiding or immune to inoculation by your preferred method(s). This also 'hardens the roots' making them stronger, stimulating growth and therefore less susceptible to fungus and bacterial infections in the future.
I find him very helpful and knowledgeable. His culture is for florida and you need to make the adjustments for your own needs but his guidelines apply to many.

Florida Orchid Growing, Month Advice, Dr. Martin Motes

:twocents:

Thanks. Very useful information. I likely err on the side of too dry if anything. Things do get quite dry in between watering and I have only just started to water things a little more during the summer. But I agree. If the pot is always damp and can never dry out it is the perfect breeding ground for bacteria and fungus.

I read somewhere that Cleary's is the same as Thyomyl (sp). Is that correct? Does anyone know?

The active ingredient in it is Thiophanate-methyl.

Unfortunately, drying probably does little to kill bacteria and fungi. They can stay dry and dormant for a long time, and resume growing their population once moist again.

If I recall correctly, David is a doctor, so hopefully he'll chime in.