Here’s a question for my boys on the wreck. I’ve been loving doing a heavy flush on my plants lately I feel like it really gives them a cleaner taste with less of that back of the throat harshness for sure. Some strains more than others. But anyway question is how do you decide when to start?
My problem is when growing new strains especially crosses and mysteries I don’t know how long are going to take. Do you base it on trichomes turning or maybe when the pistils are changed a certain percentage to red. I’m just always worried I’m going to “miss out” on some growth or late in flower or if I start flushing too early.
Also I’m in coco so I honestly think k it’s even easier than soil growers or at least takes less time.
I'm of the opinion that it doesn't make enough of a difference to justify the loss in weight
and terp/resin production.
How do you flush soil? How do you account for plants in soil looking lush and green right
up until chop, with no sign of fading (senescence)? They are as nutrient laden as they can be.
Flushing is bro science that started in the hydro circles way back when imo. I say blast'em
until you chop them. Drying and curing is wayyy more important than flushing imo. Here's
from the web supporting this position:
Is Flushing Cannabis Before Harvest Necessary?
What “flushing” means:
Flushing typically means giving your plants only water (sometimes with enzymes or finishing agents) for the last 7–14 days before harvest. The belief is it removes excess nutrients and leads to smoother, better-tasting bud.
The Science:
- No credible peer-reviewed studies definitively prove that flushing improves taste, aroma, or cannabinoid content.
- Rx Green Technologies (a respected cannabis nutrient company) ran a blind test in 2020:
- They grew cannabis under controlled conditions, flushing for 0, 7, and 14 days.
- Result: No significant difference in taste, aroma, or smoothness based on chemical analysis or blind taste panels. In fact, the unflushed plants often scored higher in flavor and THC content.
Source: Rx Green Technologies Flushing Trial PDF
Bro Science Origins:
Flushing is rooted more in
hydroponic culture and the idea of “salt buildup,” which
can be a real issue in overfed or poorly managed systems. But in modern, dialed-in systems with proper EC control? Flushing is likely
unnecessary.
Bottom line: Flushing is mostly
bro science unless your system has been overloaded. A clean, properly fed plant doesn’t need to be starved at the end.
TL;DR Summary:
| Topic | Science-Backed? | Verdict |
|---|
| Flushing before harvest |  Mostly bro science | Not necessary in clean systems |
| Plants prefer organics | They can't tell | NPK is NPK at the root level |
You’re better off focusing on:
- Proper EC/pH control
- Finishing your plants strong
- Drying/curing correctly — this affects taste more than flushing ever will.
(organic)
