Powder mold!!

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dextr0

dextr0

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Take Control Of Powdery Mildew

What is It?

One thing that you can count on in the early summer in Texas is humidity and powdery mildew. They seem to come as a team. We are going to find out how to take some really important steps to avoid powdery mildew.

Powdery Mildew is a fungus that overwinters on leaves. It is spread by the wind, splashing of rain on plants and insects and is very active during times of high humidity There are many different kinds of spores that affect various plants. Powdery mildew is host specific. The powdery mildew that affects your squash is not the same that affects your phlox.

Powdery mildew looks like white or grey concentric circles on the leaves of plants. The circles may turn black and the leaves may turn yellow and die. The fruit may fail to form or fall off of the plant.

Powdery mildew usually takes about 7-10 days to complete the life cycle. If you must spray a fungicide it is recommended that you spray it every 7 days to deep ahead of the spores from reproduction.

Defense

There are a lot of ways that you can keep from getting powdery mildew. If you take all of the precautions you should be safe. But if the wind blows some spores your way, we will go over organic solutions in the next section.

Plant Resistant Varieties – Who would have thought that mother nature could have made it so easy. When you are looking at the gardening sites there are codes to tell you what varieties are resistant to what diseases. PM is usually the code for powdery mildew.

Plant In Full Sun- Stay out of the shade. The shady environments are more humid and conducive to powdery mildew.

Air Circulation - Good air circulation is key to keeping powdery mildew at bay. So make sure to give your plants plenty of room and don’t crowd them.

Wash Off Plants - Simply washing off your plants will help to wash off the spores. Once your plants have powdery mildew, it is important to wash the spores off before you spray on a fungicide.

Water In The Morning – watering in the afternoon and evening creating a damp humid environment. Powdery mildew thrives in moist conditions.

Use Organic Fertilizers Conventional fertilizers have a high nitrogen rate compared to the slow release of organic fertilizers. High nitrogen causes fast young growth where PM thrives.

Rotate Crops - Make sure you don’t plant your crops in the same area of the garden or there may still be spores in the soil. Crop rotation is good on so many levels.

Clean Plant Debris - At the end of the season clean up plant debris and leaves and compost them or spores will form and you may be breeding a monster. It is important that you throw away infected plants with powdery mildew and do not compost them.

Disinfect Tools - Make sure that you don’t spread disease. You should be careful to disinfect your tools with one part bleach to four parts water. Make sure when you are using a tool to trim off infected leaves that you disinfect between each plant.

Cultural Methods

If you have powdery mildew there are some methods that you need to take to help get rid of it quickly. The key to success is early detection and fast treatment. If powdery mildew gets into advanced stages you might as well just pull out the plant and save yourself some money. So if you have it act fast NOW!

Start by pruning off severely infected leaves and disposing of them in the trash. Next wash off the leaves with plain old water. You are just washing the spores off of the plant A good dose of compost tea will help strengthen the plant and it have a natural fungicide action. If you want to add some garlic in there the last day of brewing, that will help as garlic has a natural fungicide as well. You want to make sure that you are applying a fungicide every 7 days until the problem is gone. If it rains, reapply. be careful with copper not to exceed the listed dose as it will build up in the soil.

Biorationals

Skim Milk - is used as a barrier and a fungicide. Use 1 part milk to 9 parts water and spray all surfaces until dripping.

Sodium Bicarbonate – 4 tsp baking soda, 1/2 tsp liquid soap, 1 gallon water, 1 tbl dormant or horticultural oil can also be added. Don’t add oil in temperatures over 90 degrees.

Cornmeal Drench 1 cup cornmeal to 1 gallon water let soak overnight. Drain and discard the solids. Spray the drench on the effected plants.

Cornmeal - 2 pounds cornmeal worked into 100 square feet of soil.

Potassium bicarbonate – a naturally occurring substance.

Azadirachtin - Made from the oil in neem tree seeds. Be sure not to apply in temperatures over 90 degrees

Sulfur - Plants can be photosensitive in summer temperatures.

Streptomyces lydicus - is a naturally occurring bacterium found in the soil. It can be applied to soil mixes or to the foliage.

L-Glutamic acid – is one of the major amino acids found in both animal and plant proteins. it is used to control powdery mildew in grapes.

Bacillus pumilis strain QST 2808 – is a naturally occurring bacterium found in both soil and water. It acts as a barrier by preventing spores from forming on plants and then colonizes the spores. It also stimulates the plants own resistance system thus inducing systemic acquired resistance (SAR).

Jojoba Oil - a naturally occurring oil. Do not use in temperatures over 90 degrees.

Copper Oxide – a naturally occurring mineral used as a dust or a spray. Brassica is phytotoxic to copper.

Trichoderma harzianum- is a naturally fungi that is used to treat several pathogens.

Bacillus subtilis QST 713 – a widespread bacterium found in air, water and soil. it works by competing for nutrients on growth sites on plants. it also works by colonizing and attaching to fungal pathogens.

Rosemary Oil – A naturally occurring oil, be careful not to use in temperatures over 90 degressor you may burn the plants.

Kaolin Kaolin clay is a particle film barrier and can offer some protection for the organic grower by blocking out the spores. Make sure to spray kaolin on both the underside and the top of the plant leaves.

Pseudozyma flocculosa is a naturally occurring fungus that is used for the control of powdery mildew in greenhouses on cucumbers and roses.

http://ediblesanmarcos.wordpress.com/library/diseases/take-control-of-powdery-mildew/

One other thing Ive heard is good is Chitosan.

vaporedout I always wondered if the milk worked. I followed a thread where dude added alot of other stuff, then milk. Which he stuck with but I always wondered. Thanx for sharing.

Oh I forgot seawater. Which makes me think of Sea salts.
 
4

4everhigh

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0
thought is share my findings from battling the demon. i just started dealing with pm for the first time. came on slowly two weeks or so with no treatment besides removal of infected leaf matter. last night the infected leafs were getting much more abundant so i had to take action. i currently have 5 girls in my perpetual flower room. kandy kushs at 3 weeks, cloud 9s at 4 weeks and blue widows at week 6. started on my widow pheno of the blue wids early on, then spread over to my more blueberry pheno of the bw's. it then hit my cloud 9s in very few small spots. all infected areas of leaf were removed last night, i wiped down the walls with rubbing alcohol and water mixture, and gave them a skim milk treatment at 9 parts water 1 part milk. the temps were runnin high 70's with 55-60 rh with lights on. i was unable to find my dehumidifier last night but today i found it under piles of shit. i woke up to no new spots of pm anywhere on any plants. so i think im going to give a couple more treatments/preventions over next week and half and see how it goes. i have the dehumidifier on 30% rh to really try and get it down. i do feel i caught it early enough for crop success. we will c
 
D

dank_

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I use GreenCure + maximum airflow + dehumidifier. There was one strain that was a PM magnet, that strain is no more.
 
B

billybadazz

233
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In veg spray once with eagle 20 wait a week spray with banner max. In flower spray once a week for 3 weeks with sns and you will be fine. If it shows up late in flower I take 3-4 table spoons of sodium bicarbonate(baking soda) to a gal. of water with 5ml of wet betty (or any surfectant) ph at 6.7 (again what ph I use) and spray when the lights come on.
 
Seamaiden

Seamaiden

Living dead girl
23,596
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It can be included in part of a good IPM for powder mold/powdery mildew, at the very least it would act as a physical barrier, like horticultural oil.
 
bloads

bloads

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Between green cure and sulfur burns, this stuff still just kept coming back. After upgrading my airflow, it just can't seem to grow anymore :)
 
G Star

G Star

46
18
how much Spectracide should i use for herb? The application rates vary from 1/2oz per gallon to 1.25oz/gal?

Is this like apples or grapes?
 
Chobble

Chobble

789
93
Currently doing the same, been doing small battle with PM and root aphids, looking at Eagle 20 EW Fungicide as an alternative to OxiDate and Sonata.

I gave up and killed my mothers and any other plants I had indoors with the Root aphids. Good luck.

Now on the story of Powder mold.

Powder Mold is systemic. Once it appears on the leaves it is really to late. You can treat it as much as you damn well please, but honestly E-20 like seamaiden recommended is your best bet to get rid of it.

I would only use E-20 on fresh cuttings. Its a known carcinogen and will hang around for a few weeks.

Now dont add any humidity, If you can try to get your room at a constant 30% (EVERYONE SHITS BRICKS) humidity for a weekish and you will hopefully kill that mold, If its really established though just finish your cycle and clean really well when your done. In my experince PM usually comes in the clones you buy from Dispensaries. Its why I still dont like Harborside to this day.

Chobble

P.S.

Oscilating fans help along with running your fan 18/6 or 24 hours a day.
 
orbad

orbad

262
43
Eagle 20 killed my mold.

Took 7.5 drops to mix 16 ounces. That should save you a bunch of crazy math and about an eighth of chronic to solve the subsequent headache.
 
Seamaiden

Seamaiden

Living dead girl
23,596
638
I gave up and killed my mothers and any other plants I had indoors with the Root aphids. Good luck.

Now on the story of Powder mold.

Powder Mold is systemic. Once it appears on the leaves it is really to late. You can treat it as much as you damn well please, but honestly E-20 like seamaiden recommended is your best bet to get rid of it.

I would only use E-20 on fresh cuttings. Its a known carcinogen and will hang around for a few weeks.

Now dont add any humidity, If you can try to get your room at a constant 30% (EVERYONE SHITS BRICKS) humidity for a weekish and you will hopefully kill that mold, If its really established though just finish your cycle and clean really well when your done. In my experince PM usually comes in the clones you buy from Dispensaries. Its why I still dont like Harborside to this day.

Chobble

P.S.

Oscilating fans help along with running your fan 18/6 or 24 hours a day.
Wow, that post was made almost 2 years ago. I haven't seen a root aphid since, but due to my knee injury I ended up losing everything. You could tell which plants had gone through the RAs, and I still have a good bit of their next-year bud left. I wish, though, that I'd known about E20 then what I know now. I will no longer use it and won't recommend it, in large part due to its known propensity to cause resistance if over-used.

Once I figure out how to work pressing the leaves of everything I'm going to learn how to raise Brix levels and do my best to maintain optimum plant health instead of chasing the cart up the hill.
 
Seamaiden

Seamaiden

Living dead girl
23,596
638
how much Spectracide should i use for herb? The application rates vary from 1/2oz per gallon to 1.25oz/gal?

Is this like apples or grapes?
What stage of growth? I used the stonefruit and grape application rates, but right now I can only suggest this, and only with great caution since going 100% organic, if we're talking about plants that are in vegetative phase and not planned on being flipped any time soon. IIRC, I used 3T/gal, so what is that... 1.5oz/gal? wait, no, that's not right. Fuck. There are 4T/quarter cup by volume, which is equal to 2oz, again by volume, right..? so that's, what... keeps coming out as 1.5oz in my head. I can't remember and it's been two years since I've dealt with it, would have to go back and look at my notes, if I can find them now. :o
 
Chobble

Chobble

789
93
Wow, that post was made almost 2 years ago. I haven't seen a root aphid since, but due to my knee injury I ended up losing everything. You could tell which plants had gone through the RAs, and I still have a good bit of their next-year bud left. I wish, though, that I'd known about E20 then what I know now. I will no longer use it and won't recommend it, in large part due to its known propensity to cause resistance if over-used.

Once I figure out how to work pressing the leaves of everything I'm going to learn how to raise Brix levels and do my best to maintain optimum plant health instead of chasing the cart up the hill.

I didnt realize it was such a grave dig. Anyways I do agree with you on using e-20 to the minimum. I only use it on the one cut I bring home from another garden.

Chobble
 
G Star

G Star

46
18
oops! i am in the pre-veg phase...receiving clones from another garden and I want to make sure they are treated before entering my room.

Please note that the Spectracide version has less myclobutanil that actual eagle 20

Unfortunately it says use about 1/2oz per gal for stone fruits and 1.25oz for grapes...quite a difference
 
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