To FLush or Not to Flush, that is the question

Being exposed to growing as many years as I have, flushing has only recently become a topic of investigation. Many of us have many different opinions whether or not to flush. We base our opinions on experience. That comes from time tested practices that allow / provide us with the knowledge to make an assumption based on certain criteria. If the criteria is different, than so are our opinions.
Having grown organically in the 60’s…(all we did was throw seeds into the dirt and water with a garden hose), to synthetic supplements (one of today’s methods), organics, living soils, hydro and alternate substrates to hydro (soil, coco, peat, clay, rockwool, etc). If you feed a plant in a blank substrate, you could grow them in any material (suitable please…not really anything). But when we grow, and most HOME GROWERS use some kind of soil (as the majority), the debate continued to Flush or NOT to flush. Finally, last year, a study was released…here is the link:

My opinion…I used to flush when I grew hydro as I used all synthetics and believed I could taste an aftertaste of my end product, hence, clear water flushes. Wanting to get my product to market ASAP, it also help in reducing the chlorophyll content so I got my product on the street SOONER…When you smoke a LOT, it is hard to really taste any difference in our stash. It is like being exposed to a particular odor,we become desensitized to something we are constantly exposed to. I WAS able to get my product out at least 2/3 weeks earlier as CURING time was greatly reduced. Effects…no difference, smell, strength, flavor…no difference.
Now, as a home grower and growing in soil, using organics, I find no need to flush. If anything, it robs my substrate of quality nutrients that I pain painstakingly try to add to my soil so I can compost and reuse it. After all, I do not throw away my garden soil every year…I compost (worms, leaves, roots, veg scraps), add top dressing and that is it.
Take it with a grain of salt but IMHO…no need to flush


I have never really flushed.

I will discontinue feeding with nutes for the last 2 weeks or so, watering as usual, but not flooding the soil to the point of major runoff.

I’ve always had good results this way.


Yea I agree I don’t generally “flush” like normal growers unless using anything outside organics. For hydro I totally gave a flush week to help get some of that excess synthetic stuff out but that was just to help rid what I gave the prior week. Other than that with organics in soil I just give water and molasses the last two weeks and let my soil kind of get “less hot” as my plants use the feed up. I generally give one heavy compost feed about two weeks before I feel chop will be so they have food for that time. Just water if they need it with molasses after that.

What’s already been developed can’t be rid, but I will say flushing does help a grower utilize all their nutrients to the fullest if they don’t compost. I don’t have space to do composting at the moment but when I can I’ll be re using my soil. So generally to get my fall fade I’ll flush a few gallons through but not enough to rid the soil of everything and kind of force the plant to use what’s inside of the fan leaves. But I always make sure to give an adjusted feeding without specific nutes to get that fall fade late term. So I guess I flush a special way haha @organigrower0624 told me about 2 nutrients I always feed with along with molasses and that’s terpinator and aphrodite’s extraction. They’ve made a massive difference in my grows.


I don’t have a lot to say indoor. What Mike and Kronic says makes sense.

There is no way to flush outdoor. My indoor grows are usually experiments so not usually flushed. The goal for plants in my garden is to get its roots in the raised beds yr2 or yr3. Yr 1 is always in small pots for selection. Traits and sex. Only so much room in the raised beds.

Sorry, that file is too big (maximum size is 4096kb). Why not upload your large file to a cloud sharing service, then paste the link? :point_left: Never Done that

In hydro I will use just water about a week before harvest. I don’t do it to flush but because the plant doesn’t need the nutes, and the water can help in fade for color. I think it was high times… They did a blind survey of flushed vs not flushed flower, and the volunteers said there was no difference in taste. Also I’ve tried both and don’t notice a difference in taste, but sometimes it can get the plants into fade/fall colors which imho is aesthetically nice if not flavor.

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Depends on the medium and nutrients you are using… if you use a certain type of soil…, there is no need to flush. Now if your blasting it with synthetic nutes I’d suggest flushing my friend… happy growing…:sunglasses:

image Scientists say no difference I’m gonna believe the research