.

https://atrium.lib.uoguelph.ca/xmlui/bitstream/handle/10214/12125/Stemeroff_Jonathan_201712_Msc_with_erratum.pdf


I’ve recently seen a discussion that was inspired by a study into cannabis production ( pdf linked above ).
One of the things the study investigated was the impact of flushing soil grown cannabis plants with nutrient free water two weeks prior to harvest to determine whether it had the intended effect of reducing nutrient concentrations in dried bud.

According to the study - “Flushing is currently standard common practice used by many cannabis producers. This involves irrigating the plants with nutrient free water for the last two weeks before harvest. The belief is that this method of irrigation will reduce the concentration of nutrients within the bud. This reduction is then believed to have impacts on the taste of the final product when consumed. Regardless of the anecdotal impacts on taste, there is little evidence that flushing the root zone during the final phase of production would result in a net export of nutrients from the maturing bud.”


So contrary to common practice the attached study suggests flushing has almost no impact on the amount of nutrients measured in the end product. The only benefit of flushing is that the grower can use water for the final two weeks with no effect on the final yield suggesting the only benefit to flushing is that the grower can save on nutrient cost during the final two weeks of the grow cycle.
I’m sure we all know someone who’s ruined a crop from over feeding but the Cannabis for this study was grown in a lab by people who really know what they are doing.


Until I read this study I was under the impression that flushing a crop is essential and to not flush is almost a sin but is it all in the dry and cure?
There’s no denying properly cured cannabis is a different beast to something that’s been flash dried and bagged within two weeks of harvest.
Is drying in a controlled environment and a proper cure where the real magic happens and the real break down of nutrients occurs (if it happens at all)?
Is flushing stoner science?
Does anyone know what the deal is with food crops and are these flushed before being sold to consumers?
Is it just cannabis farmers that flush crops?.


I would love to hear experiences and ideas around this, I think it’s a very interesting subject especially when presented with a study that goes against what is common practice.