Is Pre-harvest Flushing A Myth?

[GT21]

I tried it myself. Hahaha

 

[Douglas.C]

I tried it myself. Hahaha

Decent ash. :)

 

[GT21]

Decent ash. :)

Thanks ...Thats botanicare pro soil and dry koolbloom fed 7 times and tap water the rest

 

[MidwestToker]

The boiling point of a carbon atom is 4,000 c or 8,000 degrees F and increases with the length of the carbon chain. Lets see if you can get even a turbo torch close to those temps.

I find that I have more trouble with strains that have high Anthocyanin production or high Brix levels at harvest. So let examine it some.

Anthocyanin has a molecular structure of,
C15H11O+
Glucose
C6H12O6
Sucrose
C12H22O11
Cellulose
C6H10O5
Look at the ratios of the Carbon molecule of Anthocyanin compared to the basic plant material. We know another form of carbon reduction is from oxidation. So if we look at the conversion from Sucrose to Cellulose we see we used 6 oxygen molecules to reduce our carbon molecules by 6 also, with a single oxygen molecule in Anthocyanin you can see how there would be less Carbon reduction from oxidation.

 

[GT21]

The boiling point of a carbon atom is 4,000 c or 8,000 degrees F and increases with the length of the carbon chain. Lets see if you can get even a turbo torch close to those temps.

I find that I have more trouble with strains that have high Anthocyanin production or high Brix levels at harvest. So let examine it some.

Anthocyanin has a molecular structure of,
C15H11O+
Glucose
C6H12O6
Sucrose
C12H22O11
Cellulose
C6H10O5
Look at the ratios of the Carbon molecule of Anthocyanin compared to the basic plant material. We know another form of carbon reduction is from oxidation. So if we look at the conversion from Sucrose to Cellulose we see we used 6 oxygen molecules to reduce our carbon molecules by 6 also, with a single oxygen molecule in Anthocyanin you can see how there would be less Carbon reduction from oxidation.

This is good stuff!!! What about betacyanin? Its not a flavanoid but does produce color.. you say you have a trouble with high brix.. as in getting white ash?

 

[MidwestToker]

This is good stuff!!! What about betacyanin? Its not a flavanoid but does produce color.. you say you have a trouble with high brix.. as in getting white ash?

According to wiki they are not related but they both have a glucoside and require light for synthesis.

 

[Bannacis]

I personally grow organic and find no need to flush.........flush what ??? Lol
Do fruit and vegetable farmers flush their crops ? I don't flush my veggie garden and it tastes great! !

But Nature does flush...Bottomless pot...Fall cold rain rain rain rain...water runs off and drains away....What you call that? But I do agree with a True Living Organic grow...a flush ain't needed.

 

[1diesel1]

I flush religiously. Keeps my ladies clean. I prefer a bone meal flush through out veg and flower. Last 2 weeks of flower strait water flush.

 

[MidwestToker]

This plant was feed water only for the last month of it's life as an experiment. Still burned with a black ash even after a 3 month cure.

 

[Enforcer]

I tried it myself. Hahaha

Very cool idea. I never considered a before and after bowl pic. Here’s my contribution:

White Widow grown in coco and fed Remo nutes. I auto water multiple times a day. Once a week, a 20% runoff flush with Recharge, molasses, and kelp extract. The last 2 weeks before harvest fed only RO water and Epsom salt to an EC=0.6. This bowl was cashed after a 10 day dry and a week in the jar. Still a little harsh due to the short cure time. But the ash is pretty clean.

I couldn’t decide on with or without flash. So I just said fukit and did both. Behold the ash....

 

[gwheels]

The chart is interesting when it comes to running your vape. I used to run my bench vape at 200 to 205 C which is 392 to 400 F. I found that was the best comprimise for effect and smoke but it is activating benzene.

I use my hand helds at 170 or 180. 340 to 350 F. I think i will keep it there :D. Thanks for the chart.

 

[Glow]

Hey all just to play devils advocate a scientific study actually has demonstrated that flushing has no effect at all re reducing nutrient build up in the plant tissue. This stands to reason because from a plant science perspective removing stored nutrients by starving the plant pre harvest would not remove/reduce particularly immobile nutrients and if anything mobile nutrients such as N would head to the flowers where they are most needed which is sort of the opposite to the desired outcome people seek in flushing. Synopsis of this paper here Note: "Flushing was found to be ineffective in removing any significant amount of nutrient from the bud." Thoughts please??

 

[Enforcer]

I would contend that this “research” is subjective as it was done by a student for a Canadian collage thesis and is not a peer reviewed study. I have grown and smoked both flushed and unflushed cannabis. Flushing most definitely affects smoothness.

BTW, disregard what I said before about flushing with epsom salt. Makes the weed pretty harsh. Ah well, that’s how I learn. I have found plain water or a flushing agent works the best.

 

[Glow]

No the research is pretty solid in that tissue analysis was conducted on 3 crops. Lab work never lies. 3 separate crops were given different treatments. The first irrigation treatment was the ‘control’ which was the standard irrigation procedure used in the facility. This treatment has irrigation events every 2 to 3 days. The second irrigation treatment termed ‘mild-stress’ was an irrigation event applied every 2 days, and the third irrigation treatment termed ‘moderate-stress’ was an irrigation event applied every 3 days. Flushing occurred over the last two weeks of production when the nutrient solution was replaced with water (no nutrients) during routine irrigation events. Another flushing method was to apply an additional 10L of water without any fertilizer to the plant over two irrigation events at the start of the two-week period of water only irrigation.

What my thoughts are though is that more could be going on with flushing and things may occur at an organic level. Certainly though the idea that you can flush nutrients that have accumulated in the plant tissue flies in the face of all known plant science and all this study did was confirm what any plant scientist would already understand. The thing is, is the grow community caught up in a collective hysteria of myth or is something else going on beyond a futile attempt to flush nutrients from the plant tissue?

 

[Enforcer]

No the research is pretty solid in that tissue analysis was conducted on 3 crops. Lab work never lies. 3 separate crops were given different treatments. The first irrigation treatment was the ‘control’ which was the standard irrigation procedure used in the facility. This treatment has irrigation events every 2 to 3 days. The second irrigation treatment termed ‘mild-stress’ was an irrigation event applied every 2 days, and the third irrigation treatment termed ‘moderate-stress’ was an irrigation event applied every 3 days. Flushing occurred over the last two weeks of production when the nutrient solution was replaced with water (no nutrients) during routine irrigation events. Another flushing method was to apply an additional 10L of water without any fertilizer to the plant over two irrigation events at the start of the two-week period of water only irrigation.

What my thoughts are though is that more could be going on with flushing and things may occur at an organic level. Certainly though the idea that you can flush nutrients that have accumulated in the plant tissue flies in the face of all known plant science and all this study did was confirm what any plant scientist would already understand. The thing is, is the grow community caught up in a collective hysteria of myth or is something else going on beyond a futile attempt to flush nutrients from the plant tissue?

I don’t know about all that man. What I do know is I’ve personally done it both ways and flushing was better. Maybe it’s anecdotal, but it’s good enough for me.

 

[Glow]

The upside is that no yield or quality losses occur if you flush correctly for the last 14 days so at least growers save on inputs. It's an interesting one isn't it though? Scientifically the vote is in - as expected you can't flush nutrients from the plant tissue; that said, something else could be going on or the greatest myth of the grow culture is that flushing is a must.

 

[Enforcer]

I should add the disclaimer that I’m in coco and run multiple auto feeds per day. So when I say “flush” I mean I’m only running a leeching agent or plain RO water for the last 10 days or so. I think that 4 events per day may have a different effect than an event every 2 or 3 days.

 

[Enforcer]

The upside is that no yield or quality losses occur if you flush correctly for the last 14 days so at least growers save on inputs. It's an interesting one isn't it though? Scientifically the vote is in - as expected you can't flush nutrients from the plant tissue; that said, something else could be going on or the greatest myth of the grow culture is that flushing is a must.

Perhaps people are equating smoothness with the removal of nutrients. Those two may not be related at all. I’m just saying it was a more pleasant smoke with a good flush, that’s all.

 

[Glow]

I actually agree BTW. What I think might be occurring re flushing outcomes, occurs at an organic level and the measurement in the study may be flawed.

 

[Glow]

I should add the disclaimer that I’m in coco and run multiple auto feeds per day. So when I say “flush” I mean I’m only running a leeching agent or plain RO water for the last 10 days or so. I think that 4 events per day may have a different effect than an event every 2 or 3 days.

I agree. Good observation but again once nutrients are stored in the tissue they scientifically can't be removed through running water only for 10 days or so. The thing is that by the time you flush cell division is about nil so the plant doesn't require nutrients. It is feasible that by flushing during this period ensures the plant doesn't uptake and store more nutrients in the tissue reducing overall tissue nutrient accumulation in the harvested product (when compared to feeding throughout the entire crop cycle).