Pre harvest intervals

Good evening,

I have been doing a lot of research lately on IPM, and today more specifically on the control of botrytis. Im a new england grower and the last 4 weeks of the season are typically cold and wet, people say the biggest pot thief here is bud rot. I've been looking at practices in the wine industry and have come across a few fungicides specifically engineered for this pathogen. Vanguard (cyprodinil), Scala (pyrimethanil) , and Elevate (Fenhexamid) are at the top of the list, lets focus on Vanguard for point of discussion.

I read the EPA papers on it and it's not known to cause cancer or any other serious side effects. The label of the product says the pre harvest interval is about 7 days for most crops, 2 days for one, and then 72 days for a certain other. Without specifically focusing on Vangaurd, what causes the vast differences in PHI across different crops. And what is the safest way to apply these guidelines to cannabis?

These days I'm trying to focus on bringing main stream horticultural practices and products into my garden. The products have a much better price and are generally better quality than marijuana targeted products. It just becomes difficult for us as growers because information that would be easy to find for a tomato grower is information we have to extrapolate and put an educated guess on.

Grapes are for eating... consumption via the gut...
Most cannabis is smoked.

If those chems are ok for eating then they'd be considered ok for edibles.
However, what are the byproducts of those chems when combusted?

Example... Eagle 20... can be used on grapes but not tobacco.

If your the only one using what you grow, do whatever suits you but, if others are consumong your product, it would be in your best interest to research every chem you are considering, very carefully.

PHI variances are from a number of factors. Mobility of the chemical, concentration, crop skin texture (re: apples or cantaloupe), response to surface washing, etc.

These numbers are useless for cannabis, as the structure of the plant is somewhat unique, as is the consumption. What other product grown is smoked, vaped, eaten, applied topically, etc, ?

When researching new products, PHI is not a safety ruler. Some think they can double or triple recommendations but this is erroneous thinking. The products created by breakdown can be more toxic/persistent than their parent compounds in some instances.

Exercise extreme prudence and caution.

Agreee, I'm not trying to cut corners whatsoever as this is for mmj patients. If it's not safe then it's not happening. On the same token, fungus in buds is also incredibly toxic and sometimes it doesn't present as full blown bud rot. Have you ever broken up a seemingly good nugget to find white or brown mycelium, because I've seen it. I will be sulfur burning until week 4 or so but once buds start stacking there's not much of anything that will get inside to the stem where the infection starts, hence I'm looking for a systemic that isnt dangerous (maybe that's a unicorn that doesn't exist). Greencure is decent but it burns the shit out of pistols and doesn't penetrate. I will keep looking and report back, perhaps somebody else knows of something.