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Flushing & Leaching & Final Bud Swell

KidGrow420

On Vacation
re: Flushing & Leaching & Final Bud Swell

If you feed the plant what it needs exactly, then yes there is no need to flush. But with all the crap that people try to push onto us at stores these days (chems) yes there is a need to flush.. That being said, I am also done with this thread.
 

VladimirPutin

New Member
re: Flushing & Leaching & Final Bud Swell

If you feed the plant what it needs exactly, then yes there is no need to flush. But with all the crap that people try to push onto us at stores these days (chems) yes there is a need to flush.. That being said, I am also done with this thread.
The most valid anecdotal statement so far was about stopping nutes to reduce workload on the plant from converting chemical nutes at the roots into drawing on leaves which is easier for the plant therefore letting her focus more on calyx stacking and trichrome production.

If only this thread was not so "biblical" I think it could have been a great one.

Vlad
 

Weaselcracker

Nug of the Year: 2016 - Member of the Month: Sept 2015, Nov 2016 - Nug of the Month: Oct 2016 - Plant of the Month: May 2016
re: Flushing & Leaching & Final Bud Swell

experience is no substitute for actual knowledge
But ScienceGrow, you don't have either- last I checked your plants looked burnt to a crisp, and you're talking to people who have both, so why come on so strong? What is going to get you growing some nice plants? Experience? You might have some valid points but nobody will listen when someone is so argumentative. It defeats the purpose. It's all backwards and sounds exactly like a mirror of what you claim to be preaching against. Only reason I was hanging around this thread was to learn something new and so far it is just a bunch of silly arguing. Let's get on with the science
 

ScienceGrow

New Member
re: Flushing & Leaching & Final Bud Swell

I'll post my results in fall. If anyone else is interested in finding this out sooner, please feel free to do it yourself. More data points are always good.

I still recommend we get such data from the companies slinging Flush aides. They don't even bother giving numbers on how much better a flush is with their product vs. plain water.

Or they have tested, and didn't like the results, so didn't publish them. (I find this likely.)
 

Sandieladygro

New Member
re: Flushing & Leaching & Final Bud Swell

Hi im a first time grower and my 2 plants are 6 weeks into flower, i have loliepopped them and i think they are coming on great the buds are swelling well and they smell great, i am defo going to try your technique, can you advice if i should be giving them nutrients every day at this stage or still twice a week as i have been doing the past 6 weeks, the leaves on my plants are turning yellow and the tips are dry and i have brown spots on some leaves.
my tempature in tent is 30 and 42 humidity with light on at night its 45 humidiry and 21 temp, oh i feed them 500ml of water a day before i put light off.

Any advice would be greatfully appreciated
 

UntoldBadman

New Member
re: Flushing & Leaching & Final Bud Swell

I personally flush the last 2 weeks with treacle water only and defoliate a bit too it makes some bloody sweet tasting buds! Nice and frosty too :)

Just my 2 cents
 
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ChrisOaty

New Member
re: Flushing & Leaching & Final Bud Swell

Any updates? I'm very interested in this data as I have a science background and am a skeptic by nature. I'm compiling a lot of research to start my very first plant.
 

ShiggityFlip

Member of the Month: Jan 2016, Aug 2017 - Nug of the Month: June 2017 - Photo of the Month: Sept 2016
re: Flushing & Leaching & Final Bud Swell

I continue to not flush with water. In fact using doc buds kit there is no flushing at all. Check out doc buds kit instructions in my sig. it will take you to one of docs threads. Then find one of docs posts with links in his signature. You can post in any of his threads if you decide to get a kit. Each kit will take you from seedling to harvest for 5-6 plants. The soil takes a month to "cook" but it is a super easy and workable method that makes the best most flavorful buds I have grown in 2+ decades. I am a solid believer. New growers regularly pull out fire with Docs kit. Watering nutrient takes about 1 minute to mix and there is no pH meter. You rarely see deficiencies and doc is always there on his thread to answer any questions. He follows up promptly when any problems arrive with SOLID advice. Just look at his plants, or heck look at the top grow in my sig. It's my 3rd run with the kit.
 

Unregistered6

New Member
re: Flushing & Leaching & Final Bud Swell

Flushing/Leaching

I can understand how flushing/leaching would affect quality, but I don't think it is because unused "nutes" are being removed from anything in and of itself. What I believe is going on is that depriving the plant of (say) N forces it to start breaking down chlorophyll, and it is actually the chlorophyll or some other molecule(s) the plant can treat like that (construct and breakdown as needed) which impart the "chem" taste. Pure hypothesis, based on observation that I only notice what others call a chem taste with homegrown grade weed (fast-dried and uncured), and it is always lessened if I'm able to get even a bit of a proper cure on my buds.

So, if you've been feeding to get a nice strong, healthy plant, you've probably got a nice green plant and it will have a chem taste because that is what all the chlorophyll the plant produced tastes like. If you flush you get rid of nutrients in the growing medium, and the plant starts breaking down excess chlorophyll - they seem to like producing lots of chlorophyll when lots of N is available, and since they seem to do just as well with less N it seems reasonable to assume that some is excess - which results in less chem taste. Growers who do not overfeed don't need to flush because the plant is already wishing it had more N and is breaking down chlorophyll to get it (fan leaves turn yellow, and flowers a paler green), resulting in less chlorophyll taste.

Final Bud Swell

Hmm, which is the "final bud swell"? The last expansion phase before the bud(s) reached peak THC levels, or the one that happens if you let them go too far. IME buds go through phases where they first lengthen then fill out, and if the plant is left unharvested too long the buds will get fat, not with new growth, but because the existing seed bracts and small leaves in the buds get thicker. This later case appears to be accompanied by an increase in resin production - well, I see resin glands rupturing all over the buds yet up until that point I don't notice ruptures on the so-old-they-self-cured flowers you find at the base of a mature bud, so I don't think it is simply an age thing.


About the whole curing process, and what the tobacco guys say...

I gotta agree with them. What works for me is taking down the whole plant, stripping off any fan leaves immediately (because I don't want the possibility of them sucking water out of the main stem), then hanging the plant in a cardboard box. Ideally I would like to hang it in a RH controlled environment and keep the buds alive until they have broken down all the chlorophyll and turned a nice gold-to-brown, then slowly drop the humidity down to 5%. I have managed to get the slow drying part working fairly well, but only managed to keep them alive to the yellow-with-some-gold stage.

If you get it right, you can hold a bud by the stem and with a toothpick, starting at the base, flick off individual flowers one at a time. I'm thinking this happens when the drying is slow enough that the abscission layer that allows a seed to drop off forms, because it doesn't happen if I dry too fast.

oops, almost forgot...
Hi, I'm Unregistered6 and I'm so new around here that this is my first post in any Cannabis related forum, been growing since '79 though.

Take care,
 

James123

New Member
re: Flushing & Leaching & Final Bud Swell

I keep it simple. I listen to the plant and the plant tells me where it wants to be fed at. As long as you have your NPK ratios correct for the specific week it's in, then all you do is adjust the ppm of your mix while maintaining your ideal NPK ratios.

What you do is listen to the run off reading of the ec or ppm. For example, if you feed at 1000 ppm and the runoff comes back at 850. Your plants are happily drinking. If it comes out greater than 1000 then your plants are spitting.

If you go week by week and listen to your plant after every feed then you know when you need to flush and feed it with higher or lower ppm for that specific NPK ratio for its current weekly stage. It's that simple and my experience has shown me to feed high ppm initially and start to bring them down by week 5 slightly lowering the ppm over the last 4 weeks for my nine week og kush plant I work with. At the end of the harvest my leaves are yellow and they really pack weight last 2 weeks. I figure if my plant is still showing & spitting white hairs by week 7 then In the last 2 weeks they will really blossom. When I first started growing 16 years ago my plants would lose over 50% of their white hairs by week 7 & then I reslized I had over fed them and they stunted. And the evidence soon became obvious after listening to them after every feed. This is how I dialed in my OG cut I have and the reason why it sits as top shelf at all dispensaries. Cause I learned exactly how to feed it by using this technique.

You can do this with any strain and get the best looking, tasting and smelling weed that your genetics allow.
 

Weaselcracker

Nug of the Year: 2016 - Member of the Month: Sept 2015, Nov 2016 - Nug of the Month: Oct 2016 - Plant of the Month: May 2016
re: Flushing & Leaching & Final Bud Swell

What medium are you growing in, James? And I'd think you must need to have a very consistent technique and timing for measuring the runoff- given that the water you are adding to the pot to cause the runoff is obviously going to affect the ppm. (?)
 

James123

New Member
re: Flushing & Leaching & Final Bud Swell

What medium are you growing in, James? And I'd think you must need to have a very consistent technique and timing for measuring the runoff- given that the water you are adding to the pot to cause the runoff is obviously going to affect the ppm. (?)
6" Hugo blocks. Using 6-9 per light on average depending on veg time.

As far as the water i am using RO water but it can also be done with tap if your city water has low ppm. I just factor in that ppm but the important thing is not how high or low the ppm is. It's the change in runoff ppm that matters. If the change is decreasing your plant is happily drinking but if the change is increasing ppm then your plant is rejecting nutrient and trying to balance itself out. So this tells me when I need to flush. I don't flush once a week like these schedules tell you to. I tend to flush twice a week on average because that is what my strain tells me it wants. But this all
Depends on the strain and the change in ppm run off. This allows you to really dial in your nutes for maximum results. Most weight, best Taste and smell, best high your strain genetics permit.
 

James123

New Member
re: Flushing & Leaching & Final Bud Swell

Overall I would like to add some final thoughts to help you all out dial in your plants. There is no 1 formula fits all approach. Take all the advice on feed schedules you read from books and magazines with a grain of sand. I can even tell you that my same formula may not work the same in a different location using the same exact strain. There are a tons of variables that effect the way the plant uptakes and responds to nutrients. Things like the humidity, temperature, macro climate, sealed or not sealed room, co2 or no co2 and finally how much light you give a plant. You have to adjust for when you are using 600/750/1000 watt systems as well.

The important thing is that you figure out the essential nutrients and their correct ratios for the week you are in with your plant. This is where you adjust the ratios between NPK. I've gotten my biggest yields on OG kush (2.5 lbs per light on 1000 watt on digital ballast / 3.15 lbs per light on Gavita Pro 1000) by literally flushing the last 3 weeks and barely feeding them anything because they were spitting. Other times I've had to feed more to get similar results.

So how do you do it. For example make a mix say its at 1000 ppm. You give your plants enough water to see a few seconds of runoff coming from the rockwool at bottom to make sure you gave them a solid watering. Collect that runoff and then take ppm measurement. It should normally come back between 900-980 if plant is drinking fine. If it comes back like at 700-800 then your initial nutrient strength (ppm) is too low and you should increase the ppm of your solution next time. To save nutrients I recirculate a fresh mix for 3 days then either flush or repeat mix and process. For example day 1, I start at 1000 ppm, comes back at 900, Day 2 I feed at 900 and comes back at 840, day 3 I feed at 840 and comes back at 780. I repeat mix again at 1000.

In a bad case scenario when your plants are rejecting the nutrient. Say I feed at 1000 and then it comes back at 1120. I know I have to flush to bring them down. If the next day after flush I feed at 1000 again and they come back at 1050. Then I know my previous day flush was not good enough. Sometimes you need to flush 2-3 days to get them back on feeding mode. A sign to look for is pre mature withering white hairs. Your plants should still be spitting and having over 80% of white hairs in week 7 to continue growing. If you have over 50% brown hairs then your plant is most likely trying to finish off at this point and you will not get that explosive last 2 week monster bud growth.

The key is to listen to the change of ppm runoff in your plants. This will ensure you are optimally feeding them so they can produce their best results that their genetics allow. All the scientific stuff discussed in this thread is great. But comes with ambiguity and complications, especially if you are not an expert. My technique works for newbies and dummies.
 

ShiggityFlip

Member of the Month: Jan 2016, Aug 2017 - Nug of the Month: June 2017 - Photo of the Month: Sept 2016
re: Flushing & Leaching & Final Bud Swell

some very useful tips for non living soil growers James. here's some rep for you. I agree every plant is different. That is a useful method. Makes you wish they had a runoff meter that could tell you % of each nutrient.

welcome to the forum and here are some reps to get you going because u are already jumping in and helping!
 

pleaddafith

New Member
re: Flushing & Leaching & Final Bud Swell

Thank you for the information I'm just about to apply this theory. I just flushed my plant a four days back

Sent from my LG-H831 using 420 Magazine Mobile App
 

safeman

Well-Known Member
re: Flushing & Leaching & Final Bud Swell

do you do 6/18 in last 2 weeks along with flush? also have heard about "cutting the plant =- many outdoor cultivator do this
 

Slowpuffer

Well-Known Member
re: Flushing & Leaching & Final Bud Swell

Correct me if I'm wrong as I've done no research into this subject, but wouldn't one major difference between Tobacco and Cannabis farming be that for Tobacco they are harvesting leaves, and with Cannabis we're harvesting unfertilized flowers?

I can't think of another crop that is similar to Cannabis. I can think of many leaf, fruit and vegetable crops but no other unfertilized flower crops.

Is there any analog we can look to?
Catnip !!
 
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