I’ve had bud rot issues in the past but, only on monster colas. So I purposefully topped and trained the hell out of these plants, hoping for more, but smaller colas. Lots of fans, RH mid 40’s after three weeks of flower, and I’m down to 72F this last week of flower. Problem is colas aren’t any smaller. 80 tops the size of 1 liter bottles. Plucked half a cola out today due to rot. So with bigger colas is it impossible to prevent rot? Is it more about minimizing it? Thanks for any comments or help!
It’s naturally present in the air and very opportunistic. It just grabs a hold every chance it gets. Denser colas have a micro climate with higher humidity so they are more susceptible to getting infected. Is your humidistat at canopy level, just curious. Look into breeders like duke diamond that give you a rating how susceptible they are to things like bud rot and powdery mildew.
Botrytis cinerea can be dealt with but not easily. Those multiple million-dollar wineries deal with it too. They use products that are safe up to the day of harvest. That would be a great place to look into products to use. If you are indoors then adding a 2 micron filter to your fresh air source can trap the spores. Another proven prevention is to use a UVC light with a wavelength of between 200 to 400 nanometers for 30 minutes before the night cycle can destroy the B. Ciperea. I do not know the intensity level of the UVC needed but that should be again a good base to find out by research. Since this is a reoccurring problem I would look into growing strains that are more resistant.
JMS Stylet Oil prevents botrytis – actively growing plus spores. Also cures pm too spores and all. https://www.stylet-oil.com/ Check out the label for what all it cures. Within an hour of lights on it turns into water too so it is kind of a wonder cure imho. It’s about $32/gallon too. I like to spray it on day 1 and I don’t need to respray, but your deal may be different.
Keep the stomata open by staying in the VPD and I’ve also noticed if you let the plant go past its chop time its stops drinking as much and the pots stay wet and those plants would typically get budrot in the larger colas. Dont let the pots stay wet. When they slow down the drunking dont water in as much or as often. Hope this helps.
I have been trialing rotblock (https://www.rotblock.co/) in my current grow. Live in the tropics with humidity around 65%-90%, so bud-rot is an ongoing issue for me. cant comment on the effectiveness yet as still in week 6 of bloom, but the user trials in another forums seems promising to reduce bud-rot.
Sounds like some great advice in the previous comments. I had some bud rot a few weeks back, so I know that heart broke feeling when you notice it. I moved 2 of my fans to under the canopy instead of circulating above, haven’t had a problem since. If you already have good circulation under the canopy than I think something like JustCoolin was saying about where you are measuring the RH levels, you might need to do a complete grow room clean up, especially if you are continually having this issue. If you have an air intake for your room than you might want to think about an air filter for that, just to be sure your introducing clean air. Good luck bro.
Dang! Thanks for all the excellent info. I’ll look up the products, add more fans, and try to grow a healthier plant overall.
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Probiotic foliar sprays might be another option to check out. I know some outdoor growers do a lacto foliar or even a kombucha foliar in early flower as a preventive.
There’s other bio-based fungicide options too… check out this stuff:
https://www.arbico-organics.com/product/Regalia-biofungicide-Reynoutria-sachalinensis/natural-organic-plant-disease-control
Thanks Soup!