To flush or not to flush.......

[jmansweed]

One controversial aspect of Marijuana growth is "flushing". In regards to this discussion I think we need to clearly define what exactly it is we're talking about. Flushing for our purposes typically implies using an unusually large amount of pH balanced water to essentially leach salt and/or nutrients from our medium, and hence our plant. Simply feeding your plant pH balanced water is not quite the same thing - allowing for excessive run-off, prior to harvest, is the real purpose. Many of us flush. Why? Obviously, because we like the results - cleaner smoke, a more natural flavor and healthier product are just some of our reasons - or excuses. What we need to do to is to develop a better understanding of what exactly the "flush" is accomplishing and really how healthy for the plant and our selves it may be. In researching this, one conclusion after the next led me to believe in it's irrelevance and then again, it's importance.

First I looked into how many regular crops are "flushed" prior to harvest. The practice is really not adhered to. I primarily looked into Tobacco crops as that plant also, will be smoked. Very little information showed up, in fact most commercial farmers will apply only the nutrients and water needed, never any extra - it's a matter of economics. Excessive run-off in those conditions means food is washing away. It should have been more obvious to me initially, that tobacco companies are absolutely not worried abut removing excessive any thing from they're product. I did find and interesting comparative study however, and will link the post at the end. In any case, It's important to understand what things we are trying to remove from the our plant. Most of us agree that primarily slowing photosynthesis, and hence eliminating chlorophyll will make our smoke taste smoother. This is where things get confusing however, or I should say they become clear.

Lets consider some general science to the plant we are growing, and then discuss our influences over it. Marijuana is an Annual, this means in it's natural environment it will grow to maturity and if pollinated, will drop seed in a single season. Next season, it's seed will guarantee reproduction. Outdoors this process occurs year after year given environmental conditions are typical. We all see this occur under the sun, season after season and typically never really consider why and how this can have influence over our indoor Marijuana crop. All Annuals experience an internal process triggered from what most believe to be primarily light cycle, called Senescence. An Annual plant will begin to concentrate it's efforts into producing fruits and/or seed to insure future generations. This process is typically hormonally induced and begins when the light cycle begins to diminish. Eventually, under conditions related to senescence, the plant will slow photosynthesis on it's own and naturally draw nutrients from fan leaves to relocate energy into reproduction. So consider that out doors, under natural light deprivation, Annual plants will essentially "flush" themselves, basically to death, all to develop healthy seed. It is a natural and predictable process. I had some very interesting conversation regarding this subject and was given a basic example of how plants choose they're time to go, regardless if we flush or not - under some conditions. If we had some heavily amended soil outdoors in our garden. We could easily grow multiple types of veggies and plants including Marijuana in the same garden, in the same soil. Even with the different nutrient demands of the various plants they all thrive given the right food is in the soil. This is a perfect example of a plant choosing which and what nutrients it absorbs and when it absorbs them. This happens because the plant is reacting with the soil microbiology. Microbes like bacteria and fungi build relationships with plants and essentially trade nutrients for carb rich substances and various fluids assisting in microbial growth. It's known as a symbiotic relationship, one relies on the other. So if an Annual plant, interacting with soil life, chooses it's own uptake gathered conditions are correct, how much influence can we really have? The answer is easy, we have no influence in some conditions. Using some grow methods however, we have all the influence. Remember, adhering to strictly a plants natural and proven method of finishing it's life cycle is important to understand, however, Marijuana itself has no intention of being smoked. Adding this unnatural process of flushing may result in a product more friendly to our purpose. We don't wait for apples to fall on the ground, we pick and eat them before the plant has given them to us. Many agricultural crops, grown under the strictest organic conditions are altered in the natural process to better provide us with product. Product that at times is tastier, more nutritious and generally healthier with human intervention.

Microbial life binds to organic matter. Under organic conditions - real bio-dynamic organics where all organic matter is added to soil prior to growing a plant, and microbial life is our priority. Flushing seems irrelevant. I said it. Irrelevant. We are relying on microbial interaction and our feedings consist of typically water only in the first place. In fact, rich, organic soil will filter your water - run-off will literally be cleaner than the water added. I've flushed enormous amounts of water through organic soil, and indeed, I washed away soil life and plants showed stress. But stress was exactly it. I was now eliminated the plants known form of absorption. Yes this resulted in yellowing leaves, and the results indeed mimic senescence but what was I really accomplishing. I was forcing the plant to look to itself for food before her time, and really starving her to maturity rather than allowing her to naturally mature under normal conditions. The eventual results hypothetically should be the same. I starve the plant through excessive watering, or the plant starves itself through Senescence. With that theory in mind under strict organic conditions, in my opinion it is always wise to let the plant follow it's natural cycle when ever possible. Indoors, in controlled environments, when we switch our light cycle to 12/12 senescence essentially is triggered to begin. We do have some control however, seeding for example, is usually avoided. A plant will prolong growth when pollination does not occur. We can add growth hormones, things like sea weed and algae based additives which contain numerous growth hormones such as cytotoxins and gibberellins. Both contribute to extended growth and delayed Senescence. Many tricks of the trade can lead to larger yields and at times and extended harvest times. It is a soil food web that feeds our plants, a symbiotic environment that naturally harmonizes. Destroying the harmony, disrupting the balance can indeed induce stress and typical deficiencies, but regardless of what we add or take away, under organic conditions, the plant and it's relationship with microbial life dictate when maturity has arrived and when she is ready for harvest - not a flood of water. It should be noted that there can be exceptions to the above, such as smaller pots for example.

 

[jmansweed]

How about soiless mediums under organic conditions, ie. Bio-organic. The majority of my grows are Bio-organic. I mix very little nutrients into my medium, and rely on weekly soluble, organic teas to feed my substrate. Feeding the substrate is important here as well as the above mentioned methods. Mediums like peat, pear-lite, coco, rock-wool and many variations of this style of grow still can maintain flourishing numbers of microbial life. The symbiotic relationship applies under these circumstances as well. However, remember microbial life actively binds itself to organic matter - plant roots included. How applicable would a flush be here? There is not nearly the same density of organic matter as most Bio-dynamic grows. The mediums included here are indeed more sensitive to flushing. My plants will react more quickly, yellowing faster and maturing quickly. Microbial life here has less matter to bind to, and although healthy root systems are intact we are more able to wash some of this life away. Plants can absorb nutrients in a multitude of ways. For this discussions purpose, lets consider the symbiotic relationship with microbial life as one and the plants ability to absorb nutrients directly (as in chelated nutrients) as another. Both are effective ways a plant will feed. One way however, allows us more influence in regards to flushing. Plants will rely more upon microbial life in soil and more on it's own means of absorption in hydro type environments. We still can and do use microbial interaction in hydroponic conditions but typically applied nutrients are plant ready. Bio-organics is a blend of hydroponics and soil in many ways, including nutrient absorption. Plants actively use both methods of absorption. Flushing does have it's place here, but timing is everything. Remember Senescence will occur displaying signals of maturity and plants will begin to essentially eat themselves. Under Bio-Organic methods, I find flushing when the beginning of visual Senescence symptoms occur will greatly assist in producing cleaner smoke. Why? It's easier to dilute the available nutrients under these conditions. The substrate becomes less nutrient rich as we flush, microbial life is easier to literally wash away and the plants food source becomes more limited. Although this again can be viewed as stressing the plant, realize Senescence is eliminated nutrients at this point also, we simply are helping it along and indeed have the ability to, as our mediums provide less included organic matter to which microbial life would bind. I've directly compared this scenario - using peat based Pro-mix and results for me are the same time and again. Plants use they're supplies up more slowly relying on Senescence alone. They simply take longer to reach the stage and level of maturity I'm looking for. I actually find weight is temporarily increased with a flush. The buds swell, although after drying, production was almost identical as the unflushed plant. I see results flushing under Bio-organic conditions and make it a regular practice. Smoke is smoother and the buds take on a more mature, swollen look in my case. For the record, the unflushed plant received little nutrients the last feedings, which turned out to be only one extra. Non the less, I recommend flushing under these conditions - at the right time - to help the plant draw nutrients from herself and eliminate chlorophyll more efficiently.

In my experiences with Airoponics, DWC, Hydroton ebb and flo tables, and the more extreme forms of hydroponics that utilize loose, unstructured mediums flushing also has benefits. Although microbes can indeed live on root sytems and in reservoirs, the frequent flow of water makes it difficult for microbial life to bind to these mediums. Typically, under these conditions there is also a general lack of bio-mass. Lacking in bio-mass contributes to a lack of symbiotic life. Algae and bacteria can form "mats" and clog flow but that does not imply a thriving rhizosphere, visual populations of build up is not the same as a balanced, prolific environment. This general style of grow responds well to a flush. When growing organically or chemically nutrients can be washed away, and again timing is everything.

In almost any scenario, growing Marijuana with chemical and synthetic based nutrients flushing has it's benefit. Most of us agree on this. Nutrient salts will build in many mediums and in plant tissue, specifically when plants are confined to a small area and leached frequently with salt based nutrients. I don't use chemical fertilizers and these days even avoid chemical blends, however, I've tested them many times and with solid results. In every instance when I would feed instead of flush in late flowering plants would remain deep green and retain excessive amounts of chlorophyll creating harsh smoke, as I usually put it - head ache weed. Any one who has bought a bag of Beasters (Canadian commercial herb), knows how quality slides with chemical fertilization programs that have no regard for a flush. Many chem based fertilizer programs can increase flowering time and weight with minor application changes. Nutrients do have a role in senescence and we can prolong the symptoms with proper or improper feedings, depending on our goals. The results of flushing are most apparent when using this method of nutrient application. Chemicals and synthetic salts will and do leach from the substrate rapidly. This is made clear by our ability to quickly improve or flush pH issues out mid cycle if necessary. Chems simply respond clearly to a flush. Even blended programs promote flushing. I believe as one example, Advanced Nutrients sells flushing additives that assist in salt removal. There is simply no denying that if you grow under theses conditions flushing is well practiced for good reason.

Which method will lead to healthier smoke has yet to be scientifically tested. Perhaps the effective flush we can give chemically fed plants draws more harm-full substances from the plant than not flushing an organic one. We have to consider the smoke. What happens to these nutrients when we burn them and what levels of items in the plant lead to harsh smoke or even worse, unhealthy Marijuana. We all generally agree eliminated chlorophyll is a goal in flushing, (even the plant will try to do this on her own) but what other items do we want out of our plant at harvest time. I've heard people say weed will crackle when burned with excessive nutrients, specifically Nitrogen. I'm more prone to believing the herb may just be a little more moist than anticipated. Like wet wood. Others claim they can taste the chemicals - which I too have been guilty of. I've read that excessive amounts of Phosphorus can be harm-full when smoked, and even more so magnesium. Marijuana smoke also has high ammonium and alcohol numbers. It should be noted that THC burns at lower temperatures than the actual plant matter. If you want to truly eliminate many things from your smoke, Vaporizing your herb will probably be more efficient than actually flushing the plant prior to harvest. The point is to ultimately create healthier and smoother smoke. The color and carbon residues of smoke more dictate what may be left in our herb, and without scientific analysis we all are simply speculating here. The only real proof we have is results and our preferences. There is science to the flush that cannot be ignored, but the majority of us practice the technique. Its time however, that we all take a clear look at what it is doing for our smoke and when its applicable. Flushing is system and style dependant. I believe too many growers rule out flushing or adhere religiously to it with-out stopping to think about it's effectiveness and what we are trying to accomplish.

Sources : Urban Gardener - The Indoor Gardener - Maximum Yield - Susheng Gan : Senescence Processes in Plants - Charles Manning Child : Senescence and Rejuvenesence - http://www.erowid.org/plants/cannabis/cannabis_info3.shtml - My years of experience

 

[BBFan]

Interesting post jmansweed. Thank you for taking the time to put it up. Obviously you have done some homework here.

I have done side by side comparisons of flush vs. no-flush. I couldn't tell the difference, and no one I smoked with could tell the difference. This was done under a double blind.

The problem I can't get beyond is the fact that when people flush- it's usually late in flower. The goal as I understand it, is to get that "nute" taste out of the finished product. But this has to be based on the premise that the plant can metabolize the nutrients into bio-mass that we end up smoking; and that we can alter the molecular makeup that everything up to this point of flush has created. To me, that is beyond all scientific reason.

Essentially, flushing is predicated on the assumption that the plant will change it's molecular make-up, and become this new, altered version of itself that, although throughout it's life it has been fed these nutrients, now those nutrients are no longer there.

Imagine a tomato. Like a bud, it is almost fully formed 2 weeks before harvest- it packs on some additional weight- it ripens, but on a molecular level (apart from senescence which occurs in all fruits and vegetables at harvest) it is still the same fruit. Under the flushing premise- we can alter the taste of the tomato in these last 2 weeks by changing what we feed it. To me, that just doesn't make sense.

Flushing for excess salt build up is a different discussion and I have done this to correct a nutrient problem, and advocate doing so. However, flushing to impact flavor just goes beyond logic.

Just my opinion.

Again, thank you for the interesting read.

 

[jmansweed]

BB, I understand your point entirely, lets talk about your tomato example. My step dad is a avid tomato farmer. When he eliminates water late in feeding, the tomato's actually test better. If there is excessive rain, or he waters late in the season, the tomato's swell and become more dilute in flavor. Granted it's the opposite in regards to flushing but still apllies. It's a solid example of plants changing prior to harvest. Same fruit - but different internal fluid content.

The same thing, in only some scenerios can occur in regards to flushing Marijuana. In your taste tests, was the plant fed organically? Flushing will not change the molecular make up of a plant - it will help exhuast resourses, and hence force the plant to look to itself using the remaining stored nutreints - eliminating chlorophyll and nutreint content.

I will admit BB, I've done some tests on a few freinds myself and many people have no idea if a plant has been flushed or not. Non the less, thanks for reading - I appreciate the input....

 

[Mutt]

I'm organic pot grower and don't see any point in flushing myself.

 

[legalize_freedom]

I flush because it's the way I learned to do it. I do it mid way through to wash away any veg nutes laying in the soil, and then I do it 2 weeks and 1 week prior to harvest. For the same reason, to make sure there is nothing in the soil, and force the plants to use whatever resources it has stored in it. This is how I was taught more than anything though. I know we all have different tastes in this, and I can respect that. I would never try to convert anyone to my way of thinking on it, nor would I suddenly decide I don't need to do this anymore...it works well and I won't change it.

As far as taste tests, I have had people comment on my same strain one time that my dates were off, and I had to harvest without a flush. The people who smoked it said it was different...had a strange taste. These people don't even know that I grow it, so they definately don't have any details of the grow. I also noticed with this batch that the ash that was produced was not the soft grey ash, that crumbled easily. It was more of a black ash that held itself together.

Is it better or not...I dunno...I know I will continue to flush, just like you guys that don't do it won't start.

Thanks again Jman for takeing the time! Interesting read!

 

[BBFan]

BB, I understand your point entirely, lets talk about your tomato example. My step dad is a avid tomato farmer. When he eliminates water late in feeding, the tomato's actually test better. If there is excessive rain, or he waters late in the season, the tomato's swell and become more dilute in flavor. Granted it's the opposite in regards to flushing but still apllies. It's a solid example of plants changing prior to harvest. Same fruit - but different internal fluid content.

The same thing, in only some scenerios can occur in regards to flushing Marijuana. In your taste tests, was the plant fed organically? Flushing will not change the molecular make up of a plant - it will help exhuast resourses, and hence force the plant to look to itself using the remaining stored nutreints - eliminating chlorophyll and nutreint content.

I will admit BB, I've done some tests on a few freinds myself and many people have no idea if a plant has been flushed or not. Non the less, thanks for reading - I appreciate the input....

Hi JMan!

Interesting perspective on the tomato. I've never noticed that in veggie growing, but I never didn't notice it either . Makes sense though. But I still don't see how it changes the flesh of the fruit that's been growing for weeks simply by not feeding it for 2 weeks. I guess I don't get how the plant uptakes a nutrient and does not use it to create or perform some process- and that the nutrient is still there in it's original state and has not been immediately metabolized during uptake. You would think by now someone would have come up with a way to add flavors to tobacco or even other fruits by now by adding it to the feeding schedule.

As far as nutes go, I used Humboldt Nutrients Natural line (supposed to be organic- and a line you didn't review in your nute post by the way- again thanks for that post too!) in Happy Frog soil amended with Mexican and Jamaican bat guano. So yes, I'm using organic products- but for me it's more about the microbial activity in the soil than it is about the taste in the final product.

I've let some plants run way past their finish time before taking the final harvest. Before my recent harvest, my last batch was a sativa strain and I let some of it go an extra couple weeks to see how it affected the high. And even though I kept feeding them, they still started to yellow and die on the major vegetative growth (as is typical during late flower). But the buds and new growth stayed green- so I'm thinking photosynthesis was still going on on some level. So chlorophyll was still present in the buds.

I think this is one of those topics that have fiercely divided camps. I usually avoid getting too involved in posts where this topic is discussed for that reason. But your approach and perspective is always thought provoking and interesting. Thank you again for the effort you put into this. I always enjoy reading your posts and seeing your perspective.

 

[legalize_freedom]

BB, just out of curiosity, what did your trichs look like after letting them go for an extra 2 weeks? Did they turn black, or did the plant keep producing new ones with the new growth? I'm just curious because I've never let one go past say 80% amber. Was the buzz/taste the same?

I don't think that 1 single flush 10 days out is going to take out all of the chlorophyll...I still have some buds producing new growth at times at the very top. But if say the new growth is way slower than the rate of trichs turning amber, then I usually chop. But then I don't have a whole lot of firsthand indoor experience either, other than keeping mothers and clones, and vegging plants....most of my experience is outdoor. This current grow is only my 4th time flowering indoors. I've been lucky in that I have had several friends that were not afraid to show me thier set-ups.

 

[pcduck]

I grow in Dwc and have had plants snap off(broken stalk) and not be able to flush. Many people myself included could not tell the difference in taste or ash color or nothing.

My $0.02 on the tomato and watering. The tomato still tastes like a tomato just not as such a strong flavor when watered continuously. The tomato has a lot of water in its fruit, mj does not when consumed.

 

[BBFan]

BB, just out of curiosity, what did your trichs look like after letting them go for an extra 2 weeks? Did they turn black, or did the plant keep producing new ones with the new growth? I'm just curious because I've never let one go past say 80% amber. Was the buzz/taste the same?

Hey LF!

You get that camera yet?

The thing about that sativa grow- it was a real up buzz- I mean really up. One of the people I share with told me the first time he smoked it he had to clean his kitchen! Couldn't sit down.

So I thought I'd let some of it go, see if I could get some couch lock (or closer to it) from some of the plant. I thought maybe I was harvesting it too early. I let it go maybe another 3 weeks. It stopped packing on any significant weight (looked awful too)- but it never really changed as far as trich color and buzz- really never got any amber. It was just as uppy (is that a word?) as the batches harvested weeks earlier. I've heard sativas have opening and closing harvest windows, but I'm really not sure what that means. Maybe it could go longer, I don't know. I'm getting ready to start another batch of the same strain, so I'll play with it some more.

 

[legalize_freedom]

She bought a camera on sat. I'm not allowed to touch it until she has read the manual....lol...she knows me, I'd just start messing with it, and read the parts I needed to read (not cover to cover) to accomplish the job. So it will be a few days probably before I can post any pics of my girls. She got a Nikon coolpix S570...seems like a nice camera, but I haven't got to play with it yet.

Duck I agree with you on the taste. The time I had to chop without the flush, no one complained that it was bad or anything...they just didn't believe it was the same product...they said it tasted different. I personally didn't notice any differnce, that is why it surprised me when a few of them comented on it...wanted to know if it was really the same stuff. Like I said the only real reason I can honestly give for flushing in my case, is that it is habit, and the way that I learned.

 

[jmansweed]

Hey guys, want to give you my thoughts about some feed back here.

BB - Consider that a plant is a structure. In that structure are many things all with value in regards to growing. Not all plants, but MJ specifically has large storage capacity on a cellular level. Meaning Cannabis can and does store unused nutreints and water for reserves. It does not utilize everything she absorbs immedeatly. In a flush we are depleting the researves and forcing the plant to look to herself for food requirements. The structure remains the same - the internal fluid content changes - just like the tomato.

We don't smoke the Tomato, and regardless of what we taste in smoking MJ, whats actually in it is what is important. Although taste can't be ignored I'm willing to bet none of us can take a hit a recognize high phosphorus content for example. As I mentioned all we can do is use our preferences - without scientific research - claiming smoother tasting smoke does not indicate healthier smoke. See my point? My dog can drink coolant because it tasted good, and then it killed him.

In regards to your long flowering Sativa. Senescence is prolonged in sativa varieties. A freind of mine grows 125 day Sour D in NY. He says it could go even longer if he based maturity on his trichs. Although trich's can be a signal of maturity the entire plant needs anylization.

Lets discuss trichs for a second. When the amber color happens, it is because the trichs are oxydizing. They are basically rusting. As a trich matures oxygen reacts with thc and basically changes the cannabinoid. You guy's know this obviously, made clear by your attempt at allowing things to go beyond the typical harvest date. IMO this does change the high in my experiences. In fact I frequently look to trich color to determine how a plant will most likely effect me. In much the same way you described. Couch lock for the more amber colored herb.

Legalize, I always appreciate your input. Lets consider your habit here - of flushing. Your freinds who smoke noticed a difference in your herb when flushing was not included. For good or ill - but there was a difference. This should in some sence verify it's value. Flushing will lower mineral and nutreint content. Try a ten day flush, at any stage of growth, literally any stage and the plant will respond. Typically with yellowing leaves as the first symtom - resembling Mg def. Granted we are inducing def. but non the less we can see how a confined plant reacts to flushing.

Thank you all for reading - nothing teaches us more than healthy discussion imo.

 

[Mutt]

As one grower friend of mine put it...
Organics (specifically L.O.) is like a buffet table of food, have it all in there and let the plant pic and choose as the microbes will take care of it for you.
Where Chem is more "intravenously" force fed to the plant...here ya go..eat it.

In a flush we are depleting the researves and forcing the plant to look to herself for food requirements. The structure remains the same - the internal fluid content changes - just like the tomato.

I think this is true for liquid ferts. I think a flush is a good thing all around for the plant. I HAD to do it when i used chems in soil. Salt build-ups, outa wack PH, and just over all plant health demanded it.

But in L.O. Flushing is destroying the micro life that makes L.O. method of growing work, thus self defeating the entire process of what the grower is trying to achieve. L.O. PH is rarely an issue, mainly becuase the soils PH is swinging like crazy (and in this type of enviro theres a root coating around the roots that protect them...i'd have to look up the name again...only occurs in true organics), the only time i've had PH issues is when i screwed up the PH of the water going in i try to keep it around 7.. Even with a high N-P hot soil in L.O. the plant only took what it needed no more no less even in a rich N soil base leaves yellowed like they should towards the end...The plant knows what it wants and when. So flushing is self-defeating IMO. Your killing the lil buggies that make it all work.

Just my take on it all. as far as Hydro I have no clue.

 

[jmansweed]

Mutt - I should have clarified and I suppose that was the point of the thread in the first place, your dead right. Flushing is irrelavent under strict organic conditions - I agree.

I should have been more specific. thanks

 

[BBFan]

Great thread guys! Thanks. Very interesting information.

So the consensus here is that in organics, flushing is not necessary or perhaps even detrimental?

This has long been a discussion in the medical world regarding the benefits of vitamins (in tablet form) versus acquiring vitamins through healthy diet. There are a lot of opinions from some respectable sources, but no clear cut proof that definitively identifies which is ultimately better.

I say that because, IMO, nitrogen is nitrogen, as far as a plant is concerned. Won't it still utilize it regardless of how it got there, organically or chemically?

In my flush / no flush comparison- I couldn't tell the difference (visually) between the plants and which was depleting it's internal stores and which was still uptaking.

Thank you all again for the very interesting information and perspectives.

 

[legalize_freedom]

with my case I'm not allowing the nitrogen to be there anymore. I flush those veg nutes from my soil a week before I start 12/12. Forcing the plant to get any (N) from whatever it has stored, and whatever was not flushed from the soil. After this flush the amount of (n) that I'm allowing the plant is minimal. Not saying my way is better by any means. Like I said before this is the way I was taught to do things, and 90% of my indoor education came from a freind that grows hydro.

I agree on the TLO...I have been reading alot about that lately, and I agree with you on that to MUTT from what I have read, a flush would be hurting what you've been trying too hard to build up. I'm really wanting to try to do true living organics, I'm just not set up for it finacially at the moment. But I'm hoping in the next 2 grows I'll be able to start. I never flushed when I was guerilla growing...Imean I'm ot about to carry 10 gallons 10 miles to try to flush a few plants...lol...and that was some of the best I have grown back then.

I run FF they try to say that they are a synthetic/organic or some crap like that...but anyone with a half brain knows that they are feeding chemicals...those soluble packs are straight off the periodic chart...lol. IMO they require a flush.

Jman I really appriciate your posts, they are an asset to the site, I only wish there were 2 or 3 of you to keep it comeing more frequently! It's refreshing to be on the learning end of things on here instead of always saying things like don't cut off your leaves, or check your pH. Thank you sincerely for your contribution! Please, Please keep it coming!

 

[Mutt]

What observations and jmansweed flushing ideaology is. Organic liquid foerts, to Chem ferts, and throw in soil mixes to coco growing and hydro...every medium will have its own end resuults...but all to a common end...good bud
I LOVE this thread, it puts sooo many variables into consideration that one can only learn from it.
I agree LF keep it going and record everyones experience and there method of growing
mad props jman

 

[ledtester]

Hey J, thanks for all the hard work
I grow WW with Dutch Nutrient Formula and have tried both and my headaches tell me to flush. Now I do find that even 3 or 4 days will do rather then weeks. Flushing with flood and drain I`m sure is quite different then soil though too. The thing is no one else has complained so it might not be a plant thing but an individual one.

 

[jmansweed]

Hey Ledtester - thanks for the bump.......

Recently I started playing around w/ hydro again. Ebb and Flo, Rockwool cubes w/ Hydroton. Although I primarily grow organic, the system is still more responsive to a flush. Meaning a week of running fresh, clean water dtw seems to flush things thoroughly.

I find the more Hydro your methods are - the more effective a flush is ( in terms of time at least).

Thanks.....................Jman

 

[viper]

Flushing: pros and cons

Much time and thought has been put into the feeding needs of each part of marijuana's life cycle, yet for some reason the final stages of resin development always seem to be ignored. But the vegetative period of plant growth is only setting the platform for us to produce the trichomes that we are after.

Flushing in particular seems to be something that is over-emphasized by many of today's growers. Many growers "flush" their plants with straight water or clearing agents during the final weeks before harvest in an effort to improve taste and smokeability. The theory is that this forces the plant to use up stored nutrients that may affect these qualities. Although this is certainly true to some extent, what many are forgetting is that not all nutrients can be moved within the plant.


Nitrogen, which is the main factor in poor-tasting bud, can be moved within the plant. If not present in the root zone a plant will take it from the older leaves to support newer growth. Calcium, however, is a nutrient that cannot be moved within the plant, if it is not present in the root zone it is not available for growth. Little research has been done on nutritional requirements of cannabis during the final stages of flowering, but it seems likely that calcium is vital as it is crucial in cell division. A calcium deficiency at later stages could therefore adversely affect trichome production.

This is not as serious of a concern for soil-based growers, as lime or other calcium sources which are mixed into the soil likely will provide sufficient nutrition even while flushing with pure water. But hydroponic growers using very pure water sources with little naturally occurring calcium could have problems. Flushing is certainly a valid technique, but is easily overdone and is not a quick fix for overfeeding earlier in the flower stage.

Some studies have shown that high potassium levels have a negative influence on THC production,4 which would correlate to the general belief that while hemp crops uptake more potassium than phosphorous, the reverse seems to be true for drug and seed cannabis crops.2 A study on how to minimize THC levels in hemp crops showed that THC levels in newer leaf growth decreased as nitrogen levels were increased.5 As no THC measurement was taken from floral clusters we can only speculate that the same would likely hold true in buds. This would also explain the good results that most growers have flushing their plants, as nitrogen is the nutrient most easily flushed from the soil.