Powdery mildew ruining my life... Someone save me!

AimAim

AimAim

Well-Known Member
Powdery Mildew is "ruining your life" ?

Srsly?

I wish my life ruinations had been so simple.
 
M

MedicatedGrow

Active Member
Credits to MJ..

Introduction:
Powdery mildew is a common fungal disease that can seriously damage indoor and outdoor crops. Powdery mildew can rapidly infect crops in both vegetative and flowering stages, coating leaves, stems and buds in fungus.

Powdery mildew typically thrives in cool, damp, shaded and poorly ventilated areas. Airborne spores brought into the grow room land on leaf surfaces and will germinate given favorable conditions. High night humidity levels often trigger the growth of mildew spores. Powdery mildew can attack indoor crops year round.

Powdery mildew is almost impossible to stop in late flowering, so early detection and control is essential. Perpetual harvest, dense scrog/sog systems, and damp basement grows are particularly vulnerable to powdery mildew. Note: strains vary in their susceptibility.

This FAQ focuses on indoor prevention and treatment options. Please read Bongaloid’s Powdery Mildew FAQ for more information.

Identification, Symptoms and damage:
Early signs of powdery mildew include white powder/fuzzy patches on leaves (usually low in the canopy) and a fuzzy white coating on lower stems. Note: powdery mildew can be wiped off the leaves for a quick visual check.

These fuzzy mycelium patches produce airborne spores that rapidly attack adjacent plants; mildew will eventually coat leaves and entire plants, reducing photosynthesis, plant vigor and bud quality.

Plants on the edge of a garden, in corners and under stress are attacked first; infection usually starts in the lower canopy where conditions are optimal. As infection progresses, mildew will spread to the top of the plants and finally attack the buds.

Infected buds may appear normal; but are internally dusted with white powder (which cannot be removed by drying), and have a stale, musty/moldy smell when dry. Smoking or trimming infected buds can cause sickness and lung infections, and is not recommended. Infected leaves should be discarded. Lower buds are the most susceptible.

Powdery mildew is difficult to 100% eradicate; control requires prevention, early detection, and pro-active measures.

Preventive gardening:
Preventative gardening techniques can be effective in defending against powdery mildew.

Maintain healthy plants. Stressed plants are often attacked first, so it is important to monitor and remove unhealthy plants.

Detection. Inspect corners, edge and lower portions of the garden frequently. Remove infected leaves, or move infected plants out of the main garden.

Dont water plants at night. Reduce or stop watering before the lights have gone out to help evaporate and reduce room humidity (thnx dutchmaster).

Reduce plant density. Spread plants apart to improve air circulation. Don’t place plants directly against walls or into corners, typically areas of poor air circulation. Pull plants 6”-1’ away from walls or reflective surfaces, and blow air to these areas.

Pruning. Remove the lowest leaves as the plants mature and prune the bottom 1/3 of the plant during veg to increase airflow inside the lower canopy. Remove all unnecessary growth. Put an oscillating fan down low to blow through this pruned area.

Foliar feeding. Foliar feeding can sometimes cause excessive nighttime humidity levels. Discontinue if mildew appears.

Harvest early if mildew is a problem.

Environmental control:
Improving growroom conditions is an excellent way to passively prevent and minimize damage by powdery mildew.

Monitor humidity levels. A quality humidity gauge should be used to monitor day and night r.h levels. Avoid prolonged high humidity levels: 50-60% r.h is ideal. Humidity must be kept below 70% during the night; levels over 80% will guarantee infection within 48 hrs.

Ventilation. Constant air movement inhibits mildew, and lowers humidity. Use oscillating fans on all sides of a garden to circulate the air. Ventilate air out of the grow room periodically during the night cycle to reduce humidity from irrigation and transpiration.

Note: Once mildew is established, oscillating fans may actually spread spores throughout the garden. Stop fans, treat infected areas, and then resume airflow.

Heat night air. Warm air holds more moisture than colder air. Heat helps dry the air and lower humidity during the night cycle. Heat the room at night and exhaust the room periodically to remove this warm/moist air.

Dehumidifier.Very effective in preventing mildew from spreading. Set controls for 40-60% and let run during night cycle.

Hepa filter. Filter the intake with a Hepa filter to eliminate spores from entering room. Inspect and change filter frequently.

Ionizer / Ozone generators. Leak some output to kill airborne pathogens and spores.

* Sulphur burner. These devices vaporize (not burn) elemental sulphur, coat the room with a fine film of sulphur, inhibiting PM spores from germinating. Also inhibits insects to some degree.

Run for 12 hours initially (at night, exhaust blower off, circ fans on), then 1-4 hrs/night thereafter. Some discontinue when buds begin to form, other let it run up to the last week. Very effective prevention.

Chemical control:
Note: Chemical information sourced from maximumyield.com and cannibisculture.com

Chemical control should be considered a last resort. Chemicals should be sprayed only in veg or early flower to prevent absorption into the buds and burning bud hairs. Chemicals may have to be applied repeatedly to be effective, and may take a few days for noticeable results. Use a surfactant to help adhere chemical to leaf surface. Some chemicals are more harmful than others; follow label directions and observe precautions.

Always spot spray first. Spraying individual leaves can be an option.
Note: many chemicals will leave a residue that appears similar to powdery mildew!

* Alkaline water:
Alkaline water can affect powdery mildew, as mildew cannot grow in basic conditions. Mist plants generously with water at 8.0+ pH frequently; discontinue when buds begin to mature to prevent budrot.

[Editor's note: this does work and is effective in late flower. Alkaline water does not seem to affect buds or bud hairs. The effect is temporary, but drastically slows mildew grow and spread. Reapply every 4-5 days.]

Baking soda: Sodium Bicarbonate
"Sodium collapses the powdery mildew cell wall". Baking soda leaves an alkaline residue on the leaves, which should be washed off with water before more is applied.
Foliar spray: 15ml / gallon

Potassium Bicarbonate:
"Collapses and desiccates the mildew hyphae. Very safe, very effective contact fungicide". Kaligreen and Armicarb100.

Garden sulphur:
A common non-toxic spray, sulfur interferes with mildew cellular respiration. Spray young plants weekly before hairs form (or spray lower leaves only), then discontinue. Do not wash off. Note: dried sulphur spray looks similar to mildew. For best results, prune plants in veg/early flower, then spray lower stems and foliage. Warning: can give a sulphur taste if sprayed directly onto buds!

Foliar spray:
15-20ml sulphur powder/Liter water. Keep well mixed when spraying.
Note: will not wash off buds. Re-application may be necessary.

Neem Oil:
Protects and kills mildew by inhibiting respiration; also protects against mites and may improve plant vigor. Results are noticeable in a couple of days.

Pro-silica: (Soluble Silicon)
”… increases resistance to pathogens by accumulating in…(leaf and root) cells of plants, providing a barrier against penetration by invading fungi such as powdery mildew and Pythium. Foliar applications leave deposits of silicon…on the leaf surface that promote effective physical barriers to…infection.” Pro-silica is alkaline.

Foliar spray: 1 part in 5

SM90:
A natural plant extract in a vegetable oil base.

Foliar spray: 10ml/liter

Copper Sulphate:
"Copper ions inactivate some fungal enzyme systems, killing the mycellium."
Effective one-shot application, but production may be discontinued.

Benomyl: Apply in veg only.

Malatox:
by the chronic:
…”This is a wonder cure. Mildew completely vanishes for up to 7 weeks! Make sure you spray before the first week of flowering.”
Foliar spray: 2.5ml per liter of water.

Biological controls:

Unpasterized milk:
Note: must be fresh, not store bought (which is pasturized). Diltute 10 parts water to 1 part milk. Works, although the milk may smell.

AQ10:
A biofungicide. Ampelomyces quisqualis is a fungus that "parasites the powdery mildew organism. It offers control over a long period of time." Effective only in initial stages of infection.

Plant Shield:
Plant Shield is a foliar spray (General Hydroponics), which kills many types of leaf and root fungus. Trichoderma harzianum strain T-22. Safe to use. Takes 2-10 days.

Serenade:
"The fermentation product of a bacterium, bacillus subtillis, that inhibits cell growth of fungi and bacteria. It is effective and easy to spray or use as a dip". Contact fungicide.
Click to expand...
 
J

jayboss1

Well-Known Member
get some neem oil .spray your plants in future when in veg ,least a couple of times ,warm water night time .
I had it ,pissed me off bad time ,never had it since preventing with neem-oil .but once you sorted that shitty PM you will probably get hit with mould sooner or later .
good advice stop both ........dehumidifier keep that humidity down 45%-50% no higher .? 24-7 on constant .
keep temps warm at night when lights out . get a portable radiator -small -fan heater -put on when lights out ,keep it warm, my room at night touching- 70f -HM-45% .
 
B

BCOGYODA

Well-Known Member
Neem will help as a bit of a preventative because it puts a coating on the leaves and PM doesn't attach itself to it very easily. BUT neem will not get rid of the PM you already have.

The absolute best product on the market to 100% get rid of PM is NOVA (myclobutanil) It is NOT organic but it is a commercial fungicide. You should read up on it before you decide to use it. Best to use it early in the plants cycle and before you have flowers forming so you aren't smoking the stuff in your flowers.

Read up on it here: http://www.dowagro.com/ca/prod/nova.htm
and here: http://www.agf.gov.bc.ca/pesticides/nova-label.pdf
 
B

budleydoright

Well-Known Member
Never tried Nova but Eagle 20 was all that I could get to work. Ran 2 cycles with it and changed strains. It is systemic so once a strain has it, it's over. I also understand close proximity to a halide lamp helps control it.
 
O

onemooretime

Member
The mildew has invested in the insulation in the walls of the shed.

The best solution is to tent inside e shed and put an air filter over the air intake.
 
not4n

not4n

Well-Known Member
wash the walls and everything with a diluted bleach solution. Thin your plants out a bit, lollipopping is good too. Also, a dehumidifier, since youre working in a shed you can probably hook a hose up to the drainage pipe on it and drain it right outside, no need to dump the water. Give your plants a good rinse in some clean water, running water from a hose or heavy spray from a spray bottle is best...just using a bucket of water to dunk is no good cause the bucket of water is contaminated with tons of spores after you dunk and wash the first plant. now let them dry and really warm the shed up (25C-32C). Now take a metal garbage can or something fire resistant and place it in the middle of your grow, close all dampers and shut off all outake and intake fans. Now this is where it gets weird....everyone knows where to get those fireworks called "screamers". They just make a loud high pitched 'scream' for about 8-10 seconds, youre going to want a few of them and maybe a few more depending on the size of your room, now light them all up and put in garbage can...it is probably best if youre out of the room at this point. let them screamers scream and let the smoke hotbox your grow room for 30 minutes or so...maybe have a little fan in there to blow the sulphur smoke around. but if you did a good cleanup of the walls and plants, and then try to do this, it should buy you enough time to harvest and shut it down till your problem is resolved/cleaned and you can keep rollin on.
 
jason1976

jason1976

Well-Known Member
sativa indica pits said:
http://www.using-hydrogen-peroxide.com/peroxide-garden.html

http://hubpages.com/hub/Hydrogen-Peroxide-for-Plants found this for another member, maybe it will help, make a soulition and spray on the leaves, good luck.
Click to expand...
tried to give props on this but it says I cant give you any more rep today...lol took the thought right out of my head. also ill add lowes or homedepot sell the hanging type moisture ridders...uhmm cant think of the name right now but it wicks moisture from the air. reasonably cheap too. damp rid. that's what its called.
 
CouchlockOR

CouchlockOR

Active Member
I had powdery mildew for like a year or so and this is how I got rid of it.
1. Make your own clones
2. Don't go into your grow room after visiting another or outside working in your yard.
3. Clean your grow areas with a 10% bleach after every harvest or transfer to another grow room.
4. Keep proper environmental factors in check. 50-60% in veg and 30% and below in flower. Leaves must flutter all the time. Spores that can't stay on the plant fall off.
5. Keep the day/night temp difference to 10 degree F or less. This helps eliminate the dew point thus reducing humidity. Right after lights turn on or off is the most common time this can happen.
6. Raise the pH of the plant surfaces. This can be done with many things but what I have found to be extremely effective is GreenCure (potassium bicarbonate) and organic while in veg. Sulfur burners can be tricky to use and can ruin a flowering crop. Another good one is OxiDate. It is hydrogen dioxide. Like hydrogen peroxide but with a different ion. It is one of the only chemicals safe to spray on flowers. As it oxidizes the organic matter (powdery mildew and it's damage) the hydrogen dioxide turns into oxygen and water leaving no harmful residue. You can literially dunk fresh harvested buds into a solution of OxiDate and be completely safe.
7. last resort use a locally systemic option like eagle 20. When a local systemic is used the chemical stays in it's relative location and doesn't move about the plant. That means that when you use a local systemic in veg the chemicals are not transferred to the flowers when switched to flowering. However if sprayed while in flower then the crop is tainted.
8. Remove badly infected plants. Find PM resistant strains.
 
not4n

not4n

Well-Known Member
like i said earlier...burn a couple 'screamer' fireworks in there...you might just be surprised.
 
Dr. Who

Dr. Who

Well-Known Member
Yeah, sulfur works,,,but your leaving a coating of sulfur on EVERYTHING! Including your plants (it shows up in testing)! GROSS! I don't care for putting ANY "oil" on my plants either, more gross. That's an opinion, formed from the cinnamon/thyme/rosemary STINKY (and told taste) of some "weed" brought into my dispensary (before our state outlawed them) to attempt to sell me by a (and I use the term loosely) grower! I sent him packing after a polite explanation of why "no way".

Stay as "natural" as you can!

Horse hair tea!
 
C

caddy1988

New Member
Dr. Who said:
Yeah, sulfur works,,,but your leaving a coating of sulfur on EVERYTHING! Including your plants (it shows up in testing)! GROSS! I don't care for putting ANY "oil" on my plants either, more gross. That's an opinion, formed from the cinnamon/thyme/rosemary STINKY (and told taste) of some "weed" brought into my dispensary (before our state outlawed them) to attempt to sell me by a (and I use the term loosely) grower! I sent him packing after a polite explanation of why "no way".

Stay as "natural" as you can!

Horse hair tea!
Click to expand...


is it horse tail tea????
 
midnitetoak

midnitetoak

Active Member
You think adding a dehumidifier would help? I grow in a basement that can get very moldy after several days of rain but running a dehumidifier 24/7 mitigates this. I still end up with moldy buds from jarring them too early but mold issues in the grow room are no longer an issue good luck
 
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