Humidity, trichome volume and potency

[Rama777]

Yo! Seems like I’ve consistently seen claims that lowering the humidity down to between 30-40% rH increases the amount of trichome production.

Is that established fact in most cases? Does the isolated variable of trichome volume increase the potency of the flowers to a discernible degree?

Also if so, and of course this is strain dependent like most things, do trichomes typically continue to be produced on the buds in the final 3 weeks of flowering or are they essentially fixed by that point and simply maturing?

Or put more simply, any reason to double the energy consumption of my dehumidification to lower the humidity level in my tent at this stage for the sake of potency and yields?

 

[LoveGrowingIt]

any reason to double the energy consumption of my dehumidification to lower the humidity level in my tent at this stage for the sake of potency and yields?

I think not, but it's not a yes-or-no question. Looking at a VPD chart, the temperature would also have to be reduced to stay within a healthy VPD range at the lower RH. Temperatures in the high 60s to low 70s would be necessary. The lower temperature, however, would push the RH higher, causing the dehumidifier to work even harder. The plants would also need more water. So, several factors would need to change, but it would be difficult to know which factor(s) caused any changes.

This is an intriguing question. We mostly discuss higher RH and the avoidance of mold. I haven't seen much discussion about optimizing lower values. I have been setting my tents' RH to 53% during flowering. So, I could try lowering it to see if there's a difference. I only have seedlings now, though, so I'll have to keep this in mind when they're flowering.

 

[Rama777]

Thanks for the thoughts! As far as optimizing VPD, you are certainly correct. However, it seems to be that theory is that the alleged increase in trichome production is actually caused by the VPD stress.

But, I’ve decided not to mess with it regardless because it’s hard enough in my context to keep the humidity even down to 55%!

 

[LoveGrowingIt]

Thanks for the thoughts! As far as optimizing VPD, you are certainly correct. However, it seems to be that theory is that the alleged increase in trichome production is actually caused by the VPD stress.

I thought about the stress factor, but didn't complicate my first post with that discussion. I do believe stress can improve potency and have been doing some experimentation in that realm.

I recently saw a discussion in a Facebook group about stressing flowering plants by desiccation. The group didn't like the idea, but it relates to what you considered. It might be easier to dehydrate a plant by reducing its water than it would be by lowering the RH. I tried that recently. The yield was low, but the potency was excellent.

But, I’ve decided not to mess with it regardless because it’s hard enough in my context to keep the humidity even down to 55%!

There's that, too. My situation is the opposite. I use a humidifier to increase the RH. I think most growers say to keep it below 60% during flowering to avoid mold. I've never had mold, so 53% RH seems to be working for me.