Neem oil after burr stage

[dmunkey]

Im trying to find more info on spraying neem oil for inspect control after the plants have already formed burrs.

I see many people making comments that they are afraid to use neem after burrs have formed but i cannot find any evidence or studies to suggest that there is actually a problem with doing this.

 

[nagmay]

I don't have data on late stage neem application, but understand people's concern. Since you don't wash the end product, any remaining residue would be transferred to your beer.

What pests are you fighting? For aphid control, I can't recommend ladybugs enough. They will set up shop and keep the hops aphid free for the rest of the season (and sometimes, the following year).

 

[dmunkey]

Pesticides will come with a PHI rating (Pre Harvest Interval) for each crop that its labeled for use on. From what I can see neem oil as a 0 day PHI, in theory you'd be able to use it up until the day you harvest, obviously that wouldnt be necessary.

 

[nagmay]

Just be cautious. Preharvest interval is often set for orchards (apples, oranges, etc), where the fruit will be washed post harvest.