Flushing Cannabis Plants Is a Bad Practice Based On Flawed Science

I would like to question the practicality of flushing for the last week. Actually, I am openly challenging the entire notion of it (hehe, just for a bit of fun) but seriously now… it’s in dire need of revisiting.

I will list some points that not only challenge the absurd impracticality and illogicality of this myth, but point out how the pseudoscience behind it is fundamentally flawed (as is all pseudoscience) and can be countered by what is known about basic plant biology.

1. Robbing plants of essential nutrients at any stage of their life cycle is NOT beneficial for growth. I challenge anyone to provide a single peer reviewed paper from a reputable journal that provides evidence suggesting otherwise.

2. If this was practical, wouldn’t you expect all big agricultural hydroponic growers adopt the same practice?

3. Plants take minerals into their tissues, from their roots via the trachery elements; i.e. xylem. Once these minerals are in the plant, they are there to stay, the plant does not expel them, unless it’s through senescence-driven abscission of leaf petioles. From the trachery elements nutrients are translocated into the phloem – the plant’s ‘blood supply’ – after being integrated into various biomolecules, or are used for various metabolic functions. Where is the logic in thinking the plant ‘uses’ these up in that last week of flushing, in order to avoid smoking them? All the N P K Fe Mg Ca etc. is still there.

4. For arguments sake say we counter the last point by suggesting these minerals in their ‘raw form’ will taste ‘hasher’ or ‘nastier’ in the form of

pyrolytic breakdown products (formed when weed is burned) than artifacts of larger biomolecules of which these minerals/macro nutrients are now a part of, for example phosphorylated PO43-. Even if this was the case it still doesn’t correlate with the myth, as the transports steam in the treachery elements is measured in minutes not a week. i.e. a PO43- molecule does not wait around in these vessels for a week before subsequent translocation and modification.

5. If there was any truth to this myth, then plants grown in soil would always taste worse than plants grown in hydro. Why? Because obviously soil is not an inert medium you can flush for a week. And a plant CANNOT distinguish between a PO43- molecule that comes from soil from that of a PO43- molecule that comes from hydro solution (which also debunks another myth, but we’ll leave that one).

6. Are there studies that have conducted double blind trials to investigate if flushed weed tastes any ‘sweeter’ than unflushed weed. Again, need peer reviewed papers. And doesn’t have to be weed, can be strawberries or any other type of fruit.

7. What is the proposed mechanism to support this myth, and how is it consistent with fundamental plant biology.

8. How does starving the plant of food in the last week increase thc production in the trichome? Papers?

9. Given, under certain conditions stressed plants upregulate certain defence compounds, but they will almost certainly produce less inflorescence weight per watt of light. Growth is always retarded under stress – not promoted. Nutrient starvation is a form of stress. Looking for peer reviewed papers that suggest otherwise.

Those of you set in your ways, each to their own and best of luck to you. Those who are willing to change their views in light of new evidence, or lack thereof, be ready for increased yields by feeding those hungry ladies right up until the second you chop.

  • What do you think? Let’s start a debate – Leave a comment below.
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  1. Yep your right! that one down, only 999 more cannabis myths to go.
    Siskiyou Sam

  2. Nitrogen is a mobile element, and it can exist in a number of forms – free nitrate, free ammonium, alkaloid, amino acid, and protein. Reducing nitrogen levels to the roots at the end of the cycle will result in a reduction in the various amounts of these compounds in the leaf and bud, and clearly that could affect the aroma, flavor, and burn. For Cannabis, we may not have a detailed scientific understanding of the changes, but it doesn’t mean they don’t happen.

    One crop that is somewhat analogous is tobacco. It is a common practice there to fertilize heavily during the first part of the life cycle to assist plant growth and alkaloid synthesis, but to have rather low nitrogen levels in the last weeks – it is clear that higher nitrogen levels at the end result in a different cured product, one that is considered inferior.

    “Given, under certain conditions stressed plants upregulate certain defence compounds, but they will almost certainly produce less inflorescence weight per watt of light.” — That is apparently logical, except that the primary defense compound for cannabis flowers are the cannabinoids! Once the flower tissue is formed, it is desirable to have the plant puts lots of resources into trichome formation; the flower bud itself is not the ultimate product, rather, it is the resin on the inflorescence that people really want.