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Can we please make a Sticky for Powdery Mildew, Bud Rot, etc...
- Thread starter Dr_love
- Start date
B
bonjourbonjour
HERES THE CURE
HERES THE CURE
Best way to cure powdery mildew is a combination of everything already mentioned.
HERES THE CURE
Best way to cure powdery mildew is a combination of everything already mentioned.
- RH% 40-50
- Temps 75F-80F
- Now you have to kill the visible Mildew. Apply any antifungicide you are willing to buy and spray on your plants. Omri product during flowering and what ever you like during veg. Do during lights off
- Now it is time to add Beneficial bacteria make a mixture of milk and water (butter milk works best) 1 part milk to 2 part water is fine 1 part milk and 10 part water is fine but you will likely have to spary with this mixture a few times. Do during lights off
M
mrred
Does having the exhaust running 24/7 witha hepa filter on the intake reduce the chance of mildew?
Just want to mention - again - UV-C treatments has proved to be far better than any fungicide to prevent mildew from spreading in the Danish professional greenhouse industry.
I've looked into these... there is a company in Cali that can make them specific to entry vestibules and/or tie them in w the air intake.
Pretty cool stuff... so long as you avoid exposure.
Found that the first hour after the lights go out is when the RH wants to spike... temp drops contributing here. I run mine 24/7 which keeps the exchange high & the spikes lower.
Overall, if you start w healthy plants & run the environment well, e.g., don't crowd em & exchange the air, then all works wonderfully well... no carcinogenic sprays, no REI's, no lying to the end user...
SKUNK420
Member
I've developed a new theory or idea about powder mildew. For the last year I've battled PM one cycle clean, then next crop covered in PM and so on.... After my last PM crop I went on a room cleaning rampage: bleached everything, hepa filtered vacuumed eveything, bleached, painted, bleached etc. The A/C and dehumidiyfiers were hell to clean. That handled the room and gear. During the same time I was continously spraying my next batch of vegging clone with azamax, DM zone/pene & grotech/pene, Greenscure. A different spray everyday. What I noticed is after a week or two ( I pre-veg for about 2wks then high power 2wks) The leafs were developing a oily shean on the leaf surfaces from the repeated applications of azamax some mixes were heavier than others 15ml@32oz. max. All went well during veg no sign of PM.
I found spider mites on my plants a couple days after flipping to 12hrs. So I took a chance and raised my humidty to 60% d&n to help slow down the spider mite birth rates. I still sprayed azamax and my other sprays until buds formed 14 to 20 days. I got some floramite to handle the SM's so far so good. They not all dead but then again I didn't spray the hell out of them because I'm in flowering and everybody knows it sucks to spary that crap in flowering.
Well now I have been running my room at 60% humidity and low 80's lites on and no sign of powder mildew. Also I know for sure the increase in humidity is having positive affect on bud growth on the SM part who knows. I've read a lot of articles on PM. PM is everywhere just floating in the air etc.... So with that being the case as long as your plants are "treated" even if your humidity is on the high side 60% or so the PM should hopfully not be able to grow because the plants have been "treated". I still believe you must be a clean as possible and control your environmental conditions as perfect as possible to prevent having the ideal conditions for PM to take root and reproduce, but we are never perfect so "treating" plants is the next best thing.`I'll be get some eagle 20 soon to use in veg but will still do the azamax sprays.
When I can budget about $500+ to uv-c lighting I'll be adding it to my a/c, dehuy, carbon scrubber. I hate wasting electricity on support gear.
I've also read that PM spores can be killed at temps around 120+ degrees. Good for between crop cleanings or certain gear.
I found spider mites on my plants a couple days after flipping to 12hrs. So I took a chance and raised my humidty to 60% d&n to help slow down the spider mite birth rates. I still sprayed azamax and my other sprays until buds formed 14 to 20 days. I got some floramite to handle the SM's so far so good. They not all dead but then again I didn't spray the hell out of them because I'm in flowering and everybody knows it sucks to spary that crap in flowering.
Well now I have been running my room at 60% humidity and low 80's lites on and no sign of powder mildew. Also I know for sure the increase in humidity is having positive affect on bud growth on the SM part who knows. I've read a lot of articles on PM. PM is everywhere just floating in the air etc.... So with that being the case as long as your plants are "treated" even if your humidity is on the high side 60% or so the PM should hopfully not be able to grow because the plants have been "treated". I still believe you must be a clean as possible and control your environmental conditions as perfect as possible to prevent having the ideal conditions for PM to take root and reproduce, but we are never perfect so "treating" plants is the next best thing.`I'll be get some eagle 20 soon to use in veg but will still do the azamax sprays.
When I can budget about $500+ to uv-c lighting I'll be adding it to my a/c, dehuy, carbon scrubber. I hate wasting electricity on support gear.
I've also read that PM spores can be killed at temps around 120+ degrees. Good for between crop cleanings or certain gear.
ive noticed everything says RH between 40 and 50. i have small closet grow and recently included a dehumidifier to battle the PM. ive been running it constantly to keep the humidity as low as possible, which is usually between 20 nad 30 percent. does having my humidity this low allow more PM than at between 40 and 50? im willing to sacrifice some bud growth due to low humidity in order to eliminate the pm problems. im just hoping im not making the PM worse by having the RH on the very low end.... any thoughts are very much appreciated
B
bonjourbonjour
Will you do not want to drop it soo low that you stress your plants. So if you can set your dehumidifier to 40% then that would be perfect keep it at a constant level.
Your going to have to kill the mildew first with fungicide. Depending how far in flower you are will determine the strength of the fungicide you buy. Take a few days of giving fungicide treatments untill all visible mildew is gone from the base of the plant from the under leaves right to the brand new growth tips.
If you can get your hands on a sulphur burner give some treatments of that. After killing all visible mildew and using the burner to disinfect the room make sure your dial in your temps.
Remember temp fluctuation from day and night also attributes to PM
Good Luck!
My last grow I kept my RH around 30. I had PM everywhere. I held it back with the milk spray treatments, but its annoying because you have to reapply every 4-5 days. Saved my grow though!
I don't believe that humidity is as much of a factor as many believe, for battling PM. Also, I have found that low humidity causes major plant stress. You lose lots of yield with too low RH.
Personally, next run I will be using Eagle 20 once in veg, and once on the first week of flower. Also, I will be applying Neem once every 2 weeks until there are visible bud growth. The neem will be used to prevent the bugs and to keep the PM from ever having a chance.
I don't believe that humidity is as much of a factor as many believe, for battling PM. Also, I have found that low humidity causes major plant stress. You lose lots of yield with too low RH.
Personally, next run I will be using Eagle 20 once in veg, and once on the first week of flower. Also, I will be applying Neem once every 2 weeks until there are visible bud growth. The neem will be used to prevent the bugs and to keep the PM from ever having a chance.
Airone6120
New member
OUTDOORS PM Prevention:
OUTDOORS PM Prevention:
Can PM/Budrot be prevented outdoos?
OUTDOORS PM Prevention:
Can PM/Budrot be prevented outdoos?
loko17
Member
Yes it can.
I have a question for someone who have some experience with bud rot in late flowering.
I just spotted some bud rot on 2 main colas in my growroom where RH is unfortunatelly at 75% because of constatnt rains and me not having a dehumidifier
Im in the 6th week of flowering and was wondering if I can still spray the colas with baking soda solution and seaweed solution and can I mix these 2 together?
Ill be greatfull for all help.
I have a question for someone who have some experience with bud rot in late flowering.
I just spotted some bud rot on 2 main colas in my growroom where RH is unfortunatelly at 75% because of constatnt rains and me not having a dehumidifier
Im in the 6th week of flowering and was wondering if I can still spray the colas with baking soda solution and seaweed solution and can I mix these 2 together?
Ill be greatfull for all help.
bicycle racer
Member
save your time and money trust me use a systemic in veg and on the first day of 12/12 flip and be done with it. otherwise enjoy smoking mildew simple as that. or screw around with milk azamax(neem) serenade etc.. blah blah they do not work for long done and tried them all.
B
baccas125
I have had great results with Sovran by BASF chemicals.
S
schwagg
A dozen or so different fungus fall under the heading of Powdery Mildew, but two different fungus species are the most likely culprits. L. taurica, tends to attack warmer gardens. It prefers a temperature of about 77 °F (25 °C). S. macularis prefers a cooler temperature; however, the more virulent stain found in indoor gardens today has adapted to tolerate more heat. Both strains thrive in moderate humidity and are not injured by water. Their conidia can live in water for short periods and are mobile in it. However, strong water sprays do destroy some conidia.
CULTURAL CONTROL
Heat
Powdery mildew is sensitive to heat. Neither species will grow at 90 °F (32 °C). and will quickly perish when above 100 ° F (38 °C).
To get a complete kill maintain the temperature for an hour. This may not be a feasible option in most indoor gardens for several reasons. The first is that it may be difficult to heat the space to such a high temperature. The second is that even a single peak of 100 ° F (38 °C) affects the growth of plants. Vegetative plants with flowers or fruits in mid stage growth (weeks 3-7) may stretch a little from the experience. The heat treatment has relatively little effect on first and second week flowers or flowers nearing maturity.
You can minimize heat’s impact on plants in several ways. Heat the garden at the end of the day, as the lights are turned off. Since the plants are not photosynthesizing, they have lower water needs.
If the plants are being grown hydroponically, lower the temperature of the water to 60 degrees. Keeping the roots cool will help the upper plant parts beat the heat. It’s not difficult to do this, even if you don’t have a water chiller. Just add ice to the reservoir or flow through system. Roots of plants growing in soil can also be cooled using thermal ice packs at the base of the stem.
The heat treatment should kill off most of the fungus and its spores. The chances are there will still be some fungal re-growth. These can be eliminated using spot treatments.
Pruning
If one particular plant seems to be infected with a few tiny white spots on a few of its leaves, get a bag large enough to drop the leaves into and then cut them off into the bag. Remove the bag from the room. This prevents spores, the white powder on top of the leaves, from becoming airborne while being removed. Remember to wash your hands and clean the scissors or knife with soap and water, hydrogen peroxide, alcohol or bleach. Spray the plant with one of the sprays listed below after pruning to prevent re-infection and encourage healing.
If, you notice a re-infection a few days later, there is a good chance that this plant is very susceptible to powdery mildew and presents a good location for the infection to start and spread from. The plant should be removed immediately by placing a bag over it and removing it from the space. Then the space should be sprayed with one of the sprays listed below.
ORGANIC and IPM CONTROL
Here are some sprays that you can use to control the powdery mildew in your crop. All of these are safe to use for herb or for edible crops. Sprays are washed away by water, including rain.
Cinnamon Oil and Tea
Cinnamon is an effective destroyer of powdery mildew, with an effectiveness rate of 50-70%. It won’t kill it completely but it will keep it in check somewhat. It also potentiates other suppressive sprays so it is good to use in combination. To make your own, boil water, turn off the heat and add one ounce of ground cinnamon to one and a half pints water. Let the tea cool to room temperature. Add half a pint of 100 proof grain alcohol or rubbing alcohol and let sit. Strain the cinnamon. The spray is ready to use. A faster method is to add 2 teaspoons cinnamon oil to one pint of water and a dash of castile soap. Other herbs are also fungicidal. Clove, rosemary, and wintergreen oils are used in some botanical fungicides. The solution should consist of no more than 2% oil.
Garlic
Garlic is antifungal and anti-bacterial and has several pathways for destroying fungi including its high sulfur content. It can also be added to other anti-fungal sprays. Several garlic sprays are available commercially.
A homemade formula: Soak three ounces of crushed garlic in one ounce of neem or sesame oil and 100 proof or higher drinking alcohol or 70% or higher rubbing alcohol for a day or two. Strain. Then soak the garlic in a cup of water for a day. Strain. Mix the oil/alcohol, soaked water and 1 tablespoon liquid castile soap in a gallon container. Then fill with water and shake. The formula is ready to use.
A simpler brew consists of a teaspoon of garlic oil in a pint of water. To keep the oil and water mixed add a 1/8teaspoon of soap. Use garlic as a vaccination. Spray on new growth before there is a sign of infection.
Garlic is a general purpose insecticide as well as fungicide, so it should be used with caution on outdoor plants. It kills beneficial insects as well as plant pests.
Hydrogen Peroxide
Hydrogen peroxide (hp) is a contact fungicide that leaves no residue. It is an oxidized product of water and has an extra oxygen atom that is slightly negatively charged. When it comes in contact with the fungi the oxygen atoms attach to molecules on the cell walls, oxidizing or “burning” them.
Household hp sold in drug stores has a concentration of 3%. Garden shops sell 10% hp. Zerotol® contains 27% hydrogen peroxide and an unstated amount of peroxyacetic acid. Together they have a more potent chemistry than hp, with an activity of about 40% hp. It is considered hazardous because it can cause skin burn similar to that caused by concentrated acids.
To treat plants with drug store grade 3% hp use 4 1/2 tablespoons and fill to make a pint of solution, or a quart of hp to 3 quarts of water. With horticultural grade 10% hp use about 4 teaspoons per pint, 5 ounces per gallon. With Zerotol® use about 1 teaspoon per pint, 2 1/2 tablespoons per gallon.
Limonene
Limonene is refined from the oil of citrus rinds. It has a pleasant citrus odor and is the active ingredient in many of the new cleaning products. It also has fungicidal qualities. I’ve used pure diluted limonene and it controlled powdery mildew, but did not eradicate it. Perhaps a higher concentration would have been more successful. Start using 0.5-1% limonene in water 1/2-1 teaspoon per pint.
Milk
Milk kills powdery mildew so well that both home and commercial rose growers all over the world have adopted it for their fungicidal sprays. Use one part milk to nine parts water. I’ve only used 1% milk, but other recipes call for either whole or skim milk and use up to 1 part in 5 milk. Some recipes add garlic or cinnamon to the mix. When using more than 30% milk, a benign mold is reported to grow on top of the leaves. Use a milk spray at the first sign of infection then protect the new growth weekly.
Messenger®
Messenger’s active ingredient is a naturally occurring protein called harpin that stimulates the plant’s own natural defense system. It has been proven to promote more vigorous hardier plants that are more resistant to disease and have increased yields. It is used to prevent infection and decrease its virulence
Neem Oil
Neem oil is pressed from the seed of the neem tree (Azadirachta indica), native to Southeast Asia, but now cultivated worldwide. Neem oil has low mammalian toxicity. It degrades rapidly once it is applied so it is safe for the environment including non-target species and beneficial insects.
Neem oil protects plants with its fungicidal properties: it disrupts the organism’s metabolism on contact, forms a barrier between the plant and the invading fungus, and it inhibits spore germination. It has translinear action, that is, it is absorbed by the leaf and moves around using the leaf’s circulatory system – it can also be used as a systemic. When it is applied to the irrigation water it is absorbed by the roots and delivered throughout the plant. Adding a 0.5% solution, about 1 teaspoon per quart, to the irrigation water will protect the plant from infection.
Neem oil is best used before the plant or the garden exhibits a major infection. By using it before powdery mildew appears, it prevents the spores from germinating. It should not be used on buds or flowers.
Oil Spray
Growers have used different oil sprays to prevent and cure fungal infections. Until recently most horticultural oil sprays were made from petroleum distillates. However, most organic growers have switched to using botanical oils. Aside from the safety factor botanicals such as cottonseed, jojoba, neem and sesame oils have fungicidal properties. They can be used in combination with other spray ingredients listed here. The oils are mixed at about 1-2% concentrations. A 1% solution is about a teaspoon per pint or 3 tablespoons per gallon. Add castile soap to help the ingredients mix. Oil sprays should only be used on the leaves, not the buds or flowers. Use weekly on new growth.
pH Up
pH-Up is a generic term for alkaline pH adjustors, used to increase water pH in indoor gardens. They come as either a powder or liquid. Its active ingredient is usually lye (KOH) or potash (K2CO3).
Fungi require an acidic environment to grow and die in alkaline environments. Changing the leaf surface environment from acidic to alkaline clears up the infection. An alkaline solution with a pH of 8 will make the environment inhospitable for the fungus and will stop its growth. This is one of the simplest means of controlling the fungus. It can be used on critically infected plants.
Potassium/Sodium Bicarbonate
Potassium bicarbonate (KHCO3) and Sodium bicarbonate (NaHCO3) are wettable powders that change the pH of the leaf surface toward alkaline. Another reaction takes place; the fungus cell wall actually bursts in the presence of bicarbonate. Potassium is one of the macro-nutrients used by plants and therefore is preferred over sodium, as sodium can build up in the soil. Sodium bicarbonate can be found in your kitchen (baking soda), so some prefer it for ease of obtaining. Both are more effective when used with an oil and spreader such as castile soap. They can be used to cure bad infections and prevents new ones.
Use one teaspoon of bicarbonate powder, a teaspoon of oil and a few drops of castile soap in a pint of water, or 3 tablespoons each potassium bicarbonate and oil and a half teaspoon soap in a gallon of water. Spray on new growth.
Serenade® and Sonata®
Serenade® and Sonata® are composed of different bacteria. They use different pathways to stop mycellial growth. They are considered totally safe to humans and animals since the bacteria attack only fungi. Watch out if you are a mushroom, otherwise you are safe. The two bacteria work well together.
They are easy to use, quite safe and effective.
Sulfur
Sulfur has been used to control powdery mildew for centuries. Sulfur sprays can be used indoors but they are not popular because of residue that remains on the plant. In greenhouses gardeners use sulfur vaporizers that heat elemental sulfur to the point of vaporization. The sulfur condenses on all surfaces including the leaves. A fine deposit of very low pH sulfur granules covers the leaf surfaces. The low pH environment inhibits fungal growth. The heaters use a 60 watt light bulb to heat sulfur which is held in a container above the light. The bulb supplies enough heat to evaporate the sulfur, but not enough for it to ignite. The problem with vaporizers is that they also leave a fine sulfur film on the leaves and flowers.
Active mildew: 7 to 8 hours per night 1 to 2 times a week.
Preventative maintenance: 4 to 5 hours once a week
Vinegar
Apple cider vinegar is toxic to powdery mildew because of its high acidity (low pH). Use it at the rate of 1 tablespoon per quart of water several times a week . Some gardeners recommend alternating using vinegar with potassium bicarbonate and milk.
PREVENTION
•Isolate all new plants in a separate area where they can’t infect other plants.
•Filter incoming air to prevent spores from entering the room in the airstream.
•Install a germicidal UVC light, like the ones used in food handling areas. The light is fatal to all airborne organisms passing through the appliance. This will kill powdery mildew spores that are airborne.
•Spray the leaves with neem oil weekly. Neem oil presents both a physical barrier and a chemical deterrent.
•Cinnamon oil and cinnamon tea can also be sprayed as a powdery mildew preventative. If you are using cinnamon oil use 1 part oil to 200 parts water. (1 teaspoon oil in a liter of water.)
CULTURAL CONTROL
Heat
Powdery mildew is sensitive to heat. Neither species will grow at 90 °F (32 °C). and will quickly perish when above 100 ° F (38 °C).
To get a complete kill maintain the temperature for an hour. This may not be a feasible option in most indoor gardens for several reasons. The first is that it may be difficult to heat the space to such a high temperature. The second is that even a single peak of 100 ° F (38 °C) affects the growth of plants. Vegetative plants with flowers or fruits in mid stage growth (weeks 3-7) may stretch a little from the experience. The heat treatment has relatively little effect on first and second week flowers or flowers nearing maturity.
You can minimize heat’s impact on plants in several ways. Heat the garden at the end of the day, as the lights are turned off. Since the plants are not photosynthesizing, they have lower water needs.
If the plants are being grown hydroponically, lower the temperature of the water to 60 degrees. Keeping the roots cool will help the upper plant parts beat the heat. It’s not difficult to do this, even if you don’t have a water chiller. Just add ice to the reservoir or flow through system. Roots of plants growing in soil can also be cooled using thermal ice packs at the base of the stem.
The heat treatment should kill off most of the fungus and its spores. The chances are there will still be some fungal re-growth. These can be eliminated using spot treatments.
Pruning
If one particular plant seems to be infected with a few tiny white spots on a few of its leaves, get a bag large enough to drop the leaves into and then cut them off into the bag. Remove the bag from the room. This prevents spores, the white powder on top of the leaves, from becoming airborne while being removed. Remember to wash your hands and clean the scissors or knife with soap and water, hydrogen peroxide, alcohol or bleach. Spray the plant with one of the sprays listed below after pruning to prevent re-infection and encourage healing.
If, you notice a re-infection a few days later, there is a good chance that this plant is very susceptible to powdery mildew and presents a good location for the infection to start and spread from. The plant should be removed immediately by placing a bag over it and removing it from the space. Then the space should be sprayed with one of the sprays listed below.
ORGANIC and IPM CONTROL
Here are some sprays that you can use to control the powdery mildew in your crop. All of these are safe to use for herb or for edible crops. Sprays are washed away by water, including rain.
Cinnamon Oil and Tea
Cinnamon is an effective destroyer of powdery mildew, with an effectiveness rate of 50-70%. It won’t kill it completely but it will keep it in check somewhat. It also potentiates other suppressive sprays so it is good to use in combination. To make your own, boil water, turn off the heat and add one ounce of ground cinnamon to one and a half pints water. Let the tea cool to room temperature. Add half a pint of 100 proof grain alcohol or rubbing alcohol and let sit. Strain the cinnamon. The spray is ready to use. A faster method is to add 2 teaspoons cinnamon oil to one pint of water and a dash of castile soap. Other herbs are also fungicidal. Clove, rosemary, and wintergreen oils are used in some botanical fungicides. The solution should consist of no more than 2% oil.
Garlic
Garlic is antifungal and anti-bacterial and has several pathways for destroying fungi including its high sulfur content. It can also be added to other anti-fungal sprays. Several garlic sprays are available commercially.
A homemade formula: Soak three ounces of crushed garlic in one ounce of neem or sesame oil and 100 proof or higher drinking alcohol or 70% or higher rubbing alcohol for a day or two. Strain. Then soak the garlic in a cup of water for a day. Strain. Mix the oil/alcohol, soaked water and 1 tablespoon liquid castile soap in a gallon container. Then fill with water and shake. The formula is ready to use.
A simpler brew consists of a teaspoon of garlic oil in a pint of water. To keep the oil and water mixed add a 1/8teaspoon of soap. Use garlic as a vaccination. Spray on new growth before there is a sign of infection.
Garlic is a general purpose insecticide as well as fungicide, so it should be used with caution on outdoor plants. It kills beneficial insects as well as plant pests.
Hydrogen Peroxide
Hydrogen peroxide (hp) is a contact fungicide that leaves no residue. It is an oxidized product of water and has an extra oxygen atom that is slightly negatively charged. When it comes in contact with the fungi the oxygen atoms attach to molecules on the cell walls, oxidizing or “burning” them.
Household hp sold in drug stores has a concentration of 3%. Garden shops sell 10% hp. Zerotol® contains 27% hydrogen peroxide and an unstated amount of peroxyacetic acid. Together they have a more potent chemistry than hp, with an activity of about 40% hp. It is considered hazardous because it can cause skin burn similar to that caused by concentrated acids.
To treat plants with drug store grade 3% hp use 4 1/2 tablespoons and fill to make a pint of solution, or a quart of hp to 3 quarts of water. With horticultural grade 10% hp use about 4 teaspoons per pint, 5 ounces per gallon. With Zerotol® use about 1 teaspoon per pint, 2 1/2 tablespoons per gallon.
Limonene
Limonene is refined from the oil of citrus rinds. It has a pleasant citrus odor and is the active ingredient in many of the new cleaning products. It also has fungicidal qualities. I’ve used pure diluted limonene and it controlled powdery mildew, but did not eradicate it. Perhaps a higher concentration would have been more successful. Start using 0.5-1% limonene in water 1/2-1 teaspoon per pint.
Milk
Milk kills powdery mildew so well that both home and commercial rose growers all over the world have adopted it for their fungicidal sprays. Use one part milk to nine parts water. I’ve only used 1% milk, but other recipes call for either whole or skim milk and use up to 1 part in 5 milk. Some recipes add garlic or cinnamon to the mix. When using more than 30% milk, a benign mold is reported to grow on top of the leaves. Use a milk spray at the first sign of infection then protect the new growth weekly.
Messenger®
Messenger’s active ingredient is a naturally occurring protein called harpin that stimulates the plant’s own natural defense system. It has been proven to promote more vigorous hardier plants that are more resistant to disease and have increased yields. It is used to prevent infection and decrease its virulence
Neem Oil
Neem oil is pressed from the seed of the neem tree (Azadirachta indica), native to Southeast Asia, but now cultivated worldwide. Neem oil has low mammalian toxicity. It degrades rapidly once it is applied so it is safe for the environment including non-target species and beneficial insects.
Neem oil protects plants with its fungicidal properties: it disrupts the organism’s metabolism on contact, forms a barrier between the plant and the invading fungus, and it inhibits spore germination. It has translinear action, that is, it is absorbed by the leaf and moves around using the leaf’s circulatory system – it can also be used as a systemic. When it is applied to the irrigation water it is absorbed by the roots and delivered throughout the plant. Adding a 0.5% solution, about 1 teaspoon per quart, to the irrigation water will protect the plant from infection.
Neem oil is best used before the plant or the garden exhibits a major infection. By using it before powdery mildew appears, it prevents the spores from germinating. It should not be used on buds or flowers.
Oil Spray
Growers have used different oil sprays to prevent and cure fungal infections. Until recently most horticultural oil sprays were made from petroleum distillates. However, most organic growers have switched to using botanical oils. Aside from the safety factor botanicals such as cottonseed, jojoba, neem and sesame oils have fungicidal properties. They can be used in combination with other spray ingredients listed here. The oils are mixed at about 1-2% concentrations. A 1% solution is about a teaspoon per pint or 3 tablespoons per gallon. Add castile soap to help the ingredients mix. Oil sprays should only be used on the leaves, not the buds or flowers. Use weekly on new growth.
pH Up
pH-Up is a generic term for alkaline pH adjustors, used to increase water pH in indoor gardens. They come as either a powder or liquid. Its active ingredient is usually lye (KOH) or potash (K2CO3).
Fungi require an acidic environment to grow and die in alkaline environments. Changing the leaf surface environment from acidic to alkaline clears up the infection. An alkaline solution with a pH of 8 will make the environment inhospitable for the fungus and will stop its growth. This is one of the simplest means of controlling the fungus. It can be used on critically infected plants.
Potassium/Sodium Bicarbonate
Potassium bicarbonate (KHCO3) and Sodium bicarbonate (NaHCO3) are wettable powders that change the pH of the leaf surface toward alkaline. Another reaction takes place; the fungus cell wall actually bursts in the presence of bicarbonate. Potassium is one of the macro-nutrients used by plants and therefore is preferred over sodium, as sodium can build up in the soil. Sodium bicarbonate can be found in your kitchen (baking soda), so some prefer it for ease of obtaining. Both are more effective when used with an oil and spreader such as castile soap. They can be used to cure bad infections and prevents new ones.
Use one teaspoon of bicarbonate powder, a teaspoon of oil and a few drops of castile soap in a pint of water, or 3 tablespoons each potassium bicarbonate and oil and a half teaspoon soap in a gallon of water. Spray on new growth.
Serenade® and Sonata®
Serenade® and Sonata® are composed of different bacteria. They use different pathways to stop mycellial growth. They are considered totally safe to humans and animals since the bacteria attack only fungi. Watch out if you are a mushroom, otherwise you are safe. The two bacteria work well together.
They are easy to use, quite safe and effective.
Sulfur
Sulfur has been used to control powdery mildew for centuries. Sulfur sprays can be used indoors but they are not popular because of residue that remains on the plant. In greenhouses gardeners use sulfur vaporizers that heat elemental sulfur to the point of vaporization. The sulfur condenses on all surfaces including the leaves. A fine deposit of very low pH sulfur granules covers the leaf surfaces. The low pH environment inhibits fungal growth. The heaters use a 60 watt light bulb to heat sulfur which is held in a container above the light. The bulb supplies enough heat to evaporate the sulfur, but not enough for it to ignite. The problem with vaporizers is that they also leave a fine sulfur film on the leaves and flowers.
Active mildew: 7 to 8 hours per night 1 to 2 times a week.
Preventative maintenance: 4 to 5 hours once a week
Vinegar
Apple cider vinegar is toxic to powdery mildew because of its high acidity (low pH). Use it at the rate of 1 tablespoon per quart of water several times a week . Some gardeners recommend alternating using vinegar with potassium bicarbonate and milk.
PREVENTION
•Isolate all new plants in a separate area where they can’t infect other plants.
•Filter incoming air to prevent spores from entering the room in the airstream.
•Install a germicidal UVC light, like the ones used in food handling areas. The light is fatal to all airborne organisms passing through the appliance. This will kill powdery mildew spores that are airborne.
•Spray the leaves with neem oil weekly. Neem oil presents both a physical barrier and a chemical deterrent.
•Cinnamon oil and cinnamon tea can also be sprayed as a powdery mildew preventative. If you are using cinnamon oil use 1 part oil to 200 parts water. (1 teaspoon oil in a liter of water.)
canadiancracker
Member
once again i had powdery mildew on clones i bought. i treated them 3 times with dutchmasters zone and saturator mix. and NO more pm... not the first time these products do the trick for me. i dont even care the buy pm clones because this shit works. if your room is clean and dialed in. bring the clones to a quarentine area dip them all, clean everything and then re dip 3 days later. then bring into your area. 7 days later hit them again with a slightly stronger mix. 3ml per liter of zone and 60ml of saturator per liter. and you shouldnt have anymore problems. i have done this time and time again. like i said if your room is clean and dialed in. lots of light and ventalation, windy, you should be ready for a clean harvest. good luck
i dont know if it was mentioned here before, but grapeman is right and chimera is also right.
as i know there two specific kinds of pm which harms cannabis.
we call it "echter mehltau" and "falscher mehltau" dont know in english but its like "real pm" and "fake pm"
the deal is real pm is growing downside your leafes and it is in the plant its an infection like humans get virus or bacterial infection, and if you want to cure your plant you have to use chemics which were uptake from the plant and working inside to fight the fungus.
if not it will ever be present in any clone or what else again.
other side is what you mentioned its the fake pm which grows on upside of leafes. its like having a banana laying around thousends of spores are ever present theres no way to get rid of them, only in an area which we cant afford just for growing cannabis
air circulation not to big temperature changes (day/night) and a low humidity with a clean setup should do the job.
maybe this was said before i dont read it all but i thought its good to say i also got some pictures of "real" and "fake" pm i ll post them when i find them.
as i know there two specific kinds of pm which harms cannabis.
we call it "echter mehltau" and "falscher mehltau" dont know in english but its like "real pm" and "fake pm"
the deal is real pm is growing downside your leafes and it is in the plant its an infection like humans get virus or bacterial infection, and if you want to cure your plant you have to use chemics which were uptake from the plant and working inside to fight the fungus.
if not it will ever be present in any clone or what else again.
other side is what you mentioned its the fake pm which grows on upside of leafes. its like having a banana laying around thousends of spores are ever present theres no way to get rid of them, only in an area which we cant afford just for growing cannabis
air circulation not to big temperature changes (day/night) and a low humidity with a clean setup should do the job.
maybe this was said before i dont read it all but i thought its good to say i also got some pictures of "real" and "fake" pm i ll post them when i find them.
Interesting anology. "Real", and "Fake" Powdery Mildew?
Well I did notice that a few things Ive done over the years to avoid this crap is probably just the most basic of things. In the winter I put a small space heater directly behind my large oscillating fan, and along with a "air Tiger" ozone generator. When temperatures increase outdoors I obviously remove the heater, just to keep a real even temperature. It seems this stuff mostly attacks in the winter, when temperatures in some grow rooms spike up and down, and the humidity then pulls PD right to your grow. Its best to have a slightly more than room temperature air being blown around along with the OZ gen. I dont know this has always worked for me. Even one year when I did get it, The warmth and keeping humidity low stopped it from ever growing, even though I did maybe 3-4 times see a very, very small growth on one plant. I quickly treated it with a bit of a sulfur spray just so the spores didnt go air born.
I believe keeping an eye along with treatments will at the very least save your grow
Well I did notice that a few things Ive done over the years to avoid this crap is probably just the most basic of things. In the winter I put a small space heater directly behind my large oscillating fan, and along with a "air Tiger" ozone generator. When temperatures increase outdoors I obviously remove the heater, just to keep a real even temperature. It seems this stuff mostly attacks in the winter, when temperatures in some grow rooms spike up and down, and the humidity then pulls PD right to your grow. Its best to have a slightly more than room temperature air being blown around along with the OZ gen. I dont know this has always worked for me. Even one year when I did get it, The warmth and keeping humidity low stopped it from ever growing, even though I did maybe 3-4 times see a very, very small growth on one plant. I quickly treated it with a bit of a sulfur spray just so the spores didnt go air born.
I believe keeping an eye along with treatments will at the very least save your grow
i dont know if it was mentioned here before, but grapeman is right and chimera is also right.
as i know there two specific kinds of pm which harms cannabis.
we call it "echter mehltau" and "falscher mehltau" dont know in english but its like "real pm" and "fake pm"
the deal is real pm is growing downside your leafes and it is in the plant its an infection like humans get virus or bacterial infection, and if you want to cure your plant you have to use chemics which were uptake from the plant and working inside to fight the fungus.
if not it will ever be present in any clone or what else again.
other side is what you mentioned its the fake pm which grows on upside of leafes. its like having a banana laying around thousends of spores are ever present theres no way to get rid of them, only in an area which we cant afford just for growing cannabis
air circulation not to big temperature changes (day/night) and a low humidity with a clean setup should do the job.
maybe this was said before i dont read it all but i thought its good to say i also got some pictures of "real" and "fake" pm i ll post them when i find them.
Hillbilly419
Member
Bump
I guess im a lttle late to the game, but their is a cheap, relatively safe product that kills pm on contact and prevents its return. If you see it today, spray it today and its gone tommorow - forever.
Liquid Copper is used for organic gardening and is a death sentence to Pm, botryitis, powdery mildew and about any other fungal/bacterial disease.
For the past 30 days, my temps have been running in the mid 90's straight with jsut over 11 inches of rain during the period. Todays forcast: 95 degrees W/ 3" of rain likely. If you hang clothes on the line they will turn green/fuzzy with mould - its on everything, everywhere. Keeping mould off of big plants is a tough job but LC knocks it out.
Liquid Copper is used for organic gardening and is a death sentence to Pm, botryitis, powdery mildew and about any other fungal/bacterial disease.
For the past 30 days, my temps have been running in the mid 90's straight with jsut over 11 inches of rain during the period. Todays forcast: 95 degrees W/ 3" of rain likely. If you hang clothes on the line they will turn green/fuzzy with mould - its on everything, everywhere. Keeping mould off of big plants is a tough job but LC knocks it out.
Smoking Nomad
Member
Having humidity at 60 to 80% will tend to create pm eventually. my experience has been to use the sulfer burner 2 times a week. I have had bud that was too long on the screens and have cleaned em up w/ this method
