It's when you water out excess nutrients, salt build ups, etc. OR when you are done flowering you feed your plants just straight water to clear out all the fertilizers (about a week or two at flower's end) you have been giving them so that the herb is smoother and the flavor comes out more. Some people use natural sugars to flush the plant out like molasses and there was somebody on here that mentioned using apple juice concentrate. It removes the flavor of the fertilizer when flowering is almost finished. You may need to flush if your plants are over fertilized during growth or flowering stages if you notice the effects of over fertilization.
Essentially flushing removes all the fertilizers and salt.
Be careful not to overwater, and send the plant into a lockup, this is the most critical time of flowering but you probably have a bad plant anyway if you don't know what flushing is.
Molasses can be used throughout flowering as a flavor/aroma enhancer.
Check out Sweet Leaf from Advanced Nutrients.
Same with apple juice.
ok here is what you do 10 days before harvest water with 4x the soil amount so 5 gal of dirt =20 gal water.Dont worry about lockup and all that garbage.You will be fine 1 time flush with 4x the amount of soil.
How about instead of giving bad tips, give good ones.
Like, buy a moisture meter if you don't know what your schedule is.
Or, KEEP THE SOIL SOMEWHAT MOIST, BUT NOT WET.
Nutrient uptake depends on the amount of moisture and air in the growing medium, if it's too wet or too dry the plant locks up. So, if you "dump" a buttload of water on your plant, the flushing won't happen because the plant isn't going to soak up any of the moisture.
The best tip is wait for the soil to dry before watering again.
If you can't figure this out, BUY A MOISTURE METER.
20% no way, unless it's the only nutrient you're feeding it!
Maybe like 1%, if you're lucky.
I had the same question when I did my first grow. everybody kept saying carefull not to over water. that just confuses a beginner cause they are worried about too much water. When you are flushing what you are doing is overwatering hense the word "Flushing" so dont worry about overwatering just let the soil dry out before watering it again. When I flush I use about 5 gallons of water per plant and they show no signs of shock. so just pour the whole 5 gallons in the pots as fast as your soil can saok it up and let it drain out the bottom. then if you want to use mollasses or something just add it to the water (1-2 tbsp per gallon of water) for the rest of your waterings. Hope this helps
the whole point is so it wont take up more nutes from the soil and it uses what it has in the rest of the plant. You dont have to be such an asshole, and you should really look up the definition of flushing before you go running you mouth.