To Rinse Or Not To Rinse

[brbud]

Just some observations.

2 paths

in nature the plant uses the nutes up in the soil it is planted. By the time the plant is mature the nutes are remoived and the rain is in essence flushing the roots.

in a grow where nutes are added regularly the nutes would need to be flushed because you are continuing to add.

Flush or not, it is my belief that Nature flushes hers.....naturally

[jacklash69]

I started flushing my kali mist three days ago, and again this morning. today starts her tenth week in bloom, and she has a completely different smell than she did 3 days ago, thats for sure. much sweeter smelling

 

check her out:

 

sorry, im quite proud of her

Sorry? For what? She's a beautiful girlie

[tricloud]

Define "flush." Some people think it is watering to the point of extreme runoff, some like me don't do that and just give straight water to the plant at its' normal level. Since I stopped using chemical ferts a long time ago I've never had anything but fine-burning and tasting bud.

 

Yes, some people get leaching and flushing confused.

[Grow Thread]

when i use the term "final flush" i refer to the removal of nutrients. whether this be just watering with regular/clean/straight water for the last couple weeks, or watering until you actually see water run out the bottom of your pots(leaching), or removing the nutrient and water mixture from your hydro system and using clean water only for the last 10-14 days or so....... either way, we are depriving the plant of essential nutrients and forcing it to feed off of itself. We are also filtering all the nute/water that has been stored in the leaves/stems and replacing it with cleaner water............. as the soil vs. hydro thing, this is simply a debate that there is no "correct" answer to. we all have different palates. what "tastes" good to one person may taste like poop to another. one strain might need to be flushed longer than another. one could easily argue that the size of a plant should determine how long it should flush for?? bigger plant = more nutewater inside to replace with clean. many people who grow in soil time it so that their last 2-3 waterings are clean water....... and they have not changed their feed plan at all..... ask them and they don't flush they are, they just dont call it that.

 

 

growing in soil, most growers adopt a feed, water, water, feed program. in hydroponics we do not have this benefit. we are in full-on nute water and in feed mode all day everyday as far as the water goes. for this reason, we do "mini-flushes" of 24-48 hours throughout the cycle to remove any salt deposits/bad stuff that has built up. this "flush" is just dumping everything and using just plain water for a day or two, and then resuming with normal water/nutes again. so in this sense, there is a difference (for technical grammar purposes) between a "flush" and a "final flush".

 

at any rate, im with tricloud on the slow dry. obviously i grow in hydro. my roots are fully submerged in water until the moment i hack the plant down. it is no doubt 100% saturated when hung. i prefer to strip large fan leaves and then hang entire plants when possible...... if not, as big of branches as space allows. this ensures an even longer dry. after 4-5 days line drying, i may have some super dense BIG buds that need to be chopped into smaller pieces and paper bag dried for a few days before jarring. the plant WILL break down during curing. thats why we do it but the less there is to break down, the better off you are in my opinion.

[BDR]

I urge every grower out there that ?'s

"flushing" to do a side by side comparison.. Grow two of the same strain.. Use the same feeding schedules except continue the feeding regiment on one and only use ph balaced water on the other for the last two weeks of bloom.. In every instance there will be a drastic difference between the two.. Taste, Smell,and Smokablity differences will be noticed.. Anyone that would ? flushing either does not mind those type of meds or is a inexperienced grower.. Allowing a plant to use up those essential nutrients and sugars that have been stored is part of the plants life cycle.. Seeing spent leaves at the end of bloom is a sure sign that a plant is using it's stored energy.. No matter the type of feeding organic or not, Dirt or hydro always flush at least the last 2 weeks and 3+ weeks for those long 12-14 week finishers.. Peace, Love, and Big Buds

[avgjoe]

This is what i have been reading over on Mr Nice forums

These are 2 questions for Nevil,founder of the Seed Bank,and father of all modern breeders

 

Quote:

1, How long did you used to flush for when you was growing in rockwool back in the day?

 

2, Did you use a flushing agent or did you just use pH'd water?

 

 

I never flushed. It wasn't practical. With up to 10 rooms, you couldn't run different watering programs. I used to run veg and flower hydro systems, but I couldn't notice any difference if I did veg with flowering formula, so I dropped it.

 

What you are trying to achieve with flushing is the elimination of plant sugars in the dried product. These affect the taste negatively. If you chop the plant at the base, and slowly dry the whole plant, it will take at least a couple of days to fully die. In this period the plant uses the remaining sugars.

 

If conditions were humid, I'd remove the fan leaves, but I preferred not to. If the plant is hung upside down, the leaves dry around the bud offering natural protection. When you smoke it, it's still in pristine condition. I just hate it when people manicure wet and smear the resin around and then force dry it. That's just disrespecting the plant. I like to manicure as I'm preparing my joint. It's the natural way.

 

N.

[AbsoluteRoyal]

good information avgjoe!, thank you for sharing

[avgjoe]

here's the link to the page

http://www.mrnice.nl/forum/showthread.php?t=4308&page=34

post#336

[MI Compassion]

http://www.stonerforums.com/lounge/growfaq/1712.html

 

A critical look at preharvest flushing

 

Pre harvest flushing is a controversial topic. Flushing is supposed to improve taste of the final bud by either giving only pure water, clearing solutions or extensive flushing for the last 7-14 days of flowering. While many growers claim a positive effect, others deny any positive influence or even suggest reduced yield and quality.

 

The theory of pre harvest flushing is to remove nutrients from the grow medium/root zone. A lack of nutrients creates a deficiency, forcing the plant to translocate and use up its internal nutrient compounds.

 

Nutrient fundamentals and uptake:

 

The nutrient uptake process is explained in this faq.

 

A good read about plant nutrition can be found here.

 

Until recently it was common thought that all nutrients are absorbed by plant roots as ions of mineral elements. However in newer studies more and more evidence emerged that additionally plant roots are capable of taking up complex organic molecules like amino acids directly thus bypassing the mineralization process.

 

The major nutrient uptake processes are:

 

1) Active transport mechanism into root hairs (the plant has to put energy in it, ATP driven) which is selective to some degree. This is one way the plant (being immobile) can adjust to the environment.

 

2) Passive transport (diffusion) through symplast to endodermis.

 

http://www.biol.sc.edu/courses/bio102/f99-3637.html

 

http://www.hort.wisc.edu/cran/Publications/2001 Proceedings/min_nutr.pdf

 

The claim only ‘chemical’ ferted plants need to be flushed should be taken with a grain of salt. Organic and synthetic ferted plants take up mineral ions alike, probably to a different degree though. Many influences play key roles in the taste and flavor of the final bud, like the nutrition balance and strength throughout the entire life cycle of the plant, the drying and curing process and other environmental conditions.

 

3) Active transport mechanism of organic molecules into root hairs via endocytosis.

 

http://acd.ucar.edu/~eholland/encyc6.html

 

Here is a simplified overview of nutrient functions:

 

Nitrogen is needed to build chlorophyll, amino acids, and proteins. Phosphorus is necessary for photosynthesis and other growth processes. Potassium is utilized to form sugar and starch and to activate enzymes. Magnesium also plays a role in activating enzymes and is part of chlorophyll. Calcium is used during cell growth and division and is part of the cell wall. Sulfur is part of amino acids and proteins.

 

Plants also require trace elements, which include boron, chlorine, copper, iron, manganese, sodium, zinc, molybdenum, nickel, cobalt, and silicon.

 

Copper, iron, and manganese are used in photosynthesis. Molybdenum, nickel, and cobalt are necessary for the movement of nitrogen in the plant. Boron is important for reproduction, while chlorine stimulates root growth and development. Sodium benefits the movement of water within the plant and zinc is neeeded for enzymes and used in auxins (organic plant hormones). Finally, silicon helps to build tough cell walls for better heat and drought tolerance.

 

http://www.sidwell.edu

 

You can get an idea from this how closely all the essential elements are involved in the many metabolic processes within the plant, often relying on each other.

 

Nutrient movement and mobility inside the plant:

 

Besides endocytosis, there are two major pathways inside the plant, the xylem and the phloem. When water and minerals are absorbed by plant roots, these substances must be transported up to the plant's stems and leaves for photosynthesis and further metabolic processes. This upward transport happens in the xylem. While the xylem is able to transport organic compounds, the phloem is much more adapted to do so.

 

The organic compounds thus originating in the leaves have to be moved throughout the plant, upwards and downwards, to where they are needed. This transport happens in the phloem. Compounds that are moving through the phloem are mostly:

Sugars as sugary saps, organic nitrogen compounds (amino acids and amides, ureides and legumes), hormones and proteins.

 

http://www.sirinet.net

 

Not all nutrient compounds are moveable within the plant.

 

1) N, P, K, Mg and S are considered mobile: they can move up and down the plant in both xylem and phloem.

Deficiency appears on old leaves first.

 

2) Ca, Fe, Zn, Mo, B, Cu, Mn are considered immobile: they only move up the plant in the xylem.

Deficiency appears on new leaves first.

 

http://generalhorticulture.tamu.edu

 

Storage organelles:

 

Salts and organic metabolites can be stored in storage organelles. The most important storage organelle is the vacuole, which can contribute up to 90% of the cell volume. The majority of compounds found in the vacuole are sugars, polysaccharides, organic acids and proteins though.

 

http://jeb.biologists.org.pdf

 

Translocation:

 

Now that the basics are explained, we can take a look at the translocation process. It should be already clear that only mobile elements can be translocated through the phloem. Immobile elements cant be translocated and are not more available to the plant for further metabolic processes and new plant growth.

 

Since flushing (in theory) induces a nutrient deficiency in the rootzone, the translocation process aids in the plants survival. Translocation is transportation of assimilates through the phloem from source (a net exporter of assimilate) to sink (a net importer of assimilate). Sources are mostly mature fan leaves and sinks are mostly apical meristems, lateral meristem, fruit, seed and developing leaves etc.

 

You can see this by the yellowing and later dying of the mature fan leaves from the second day on after flushing started. Developing leaves, bud leaves and calyxes don’t serve as sources, they are sinks. Changes in those plant parts are due to the deficient immobile elements which start to indicate on new growth first.

 

Unfortunately, several metabolic processes are unable to take place anymore since other elements needed are no longer available (the immobile ones). This includes processes where nitrogen and phosphorus, which have likely the most impact on taste, are involved.

 

For example nitrogen: usually plants use nitrogen to form plant proteins. Enzyme systems rapidly reduce nitrate-N (NO3-) to compounds that are used to build amino-nitrogen which is the basis for amino acids. Amino acids are building blocks for proteins, most of them are plant enzymes responsible for all the chemical changes important for plant growth.

 

Sulfur and calcium among others have major roles in production and activating of proteins, thereby decreasing nitrate within the plant. Excess nitrate within the plant may result from unbalanced nutrition rather than an excess of nitrogen.

 

http://muextension.missouri.edu

 

Summary:

 

Preharvest flushing puts the plant(s) under serious stress. The plant has to deal with nutrient deficiencies in a very important part of its cycle. Strong changes in the amount of dissolved substances in the root-zone stress the roots, possibly to the point of direct physical damage to them. Many immobile elements are no more available for further metabolic processes. We are loosing the fan leaves and damage will show likely on new growth as well.

 

The grower should react in an educated way to the plant needs. Excessive, deficient or unbalanced levels should be avoided regardless the nutrient source. Nutrient levels should be gradually adjusted to the lesser needs in later flowering. Stress factors should be limited as far as possible. If that is accomplished throughout the entire life cycle, there shouldn’t be any excessive nutrient compounds in the plants tissue. It doesn’t sound likely to the author that you can correct growing errors (significant lower mobile nutrient compound levels) with preharvest flushing.

 

Drying and curing (when done right) on the other hand have proved (In many studies) to have a major impact on taste and flavour, by breaking down chlorophylls and converting starches into sugars. Most attributes blamed on unflushed buds may be the result of unbalanced nutrition and/or overfert and unproper drying/curing.

[DLD420]

For the most part I agree with you, but I fear we part ways on this one. First, understand I am not suggesting that anyone not flush. I was only saying that common knowledge holds it to be a little less mandatory than when using chem ferts.That is one of the benefits I hear people giving for growing organic.Who knows, I never flushed the old apple tree and the apples never tasted like my pee of the dogs. To answer your question, no I wouldn't drink my ferts, but i wouldn't eat a lot of the bunny muffin fish eat, no interest in the diet of a deer. When the plant takes up guano it doesn't magikally become full of petrified bat turds.Seems that line of thought is a wee bit off.

can't stoplaffin petrified bat turds lmao

[Sativasfied]

Flush the salts.

Evaporate the water.

Keep the sugars.

 

 

[MI Compassion]

Flush the salts.

Evaporate the water.

Keep the sugars.

 

Why would someone want to do this?

[Sativasfied]

Why would someone want to do this?

 

Why would someone want to flush salts?

 

or

 

Why would someone want to evaporate the water?

 

or

 

Why would someone want to keep sugars?

 

I will quote what you posted

 

Drying and curing (when done right) on the other hand have proved (In many studies) to have a major impact on taste and flavour, by breaking down chlorophylls and converting starches into sugars.

[MI Compassion]

Why would someone want to flush salts?

 

or

 

Why would someone want to evaporate the water?

 

or

 

Why would someone want to keep sugars?

 

I will quote what you posted

I guess I don't understand what you meant by "keep the sugars"...

 

The way your post was worded I took it as you where saying you flush the medium to remove salt deposits, collect the runoff, and evaporate it to save the sugars for some other use, which I don't see the point in doing.

 

Do you mean keep the sugars in the plant so they can fully break down into starches?

[Sativasfied]

I guess I don't understand what you meant by "keep the sugars"...

 

The way your post was worded I took it as you where saying you flush the medium to remove salt deposits, collect the runoff, and evaporate it to save the sugars for some other use, which I don't see the point in doing.

 

Do you mean keep the sugars in the plant so they can fully break down into starches?

 

Nope. Flush to rinse the deposited salts out, Dry to evaporate the water in the plant, Cure to break down chlorophyll and convert the starches into sugars. Sugar is sweet right?

[MI Compassion]

Nope. Flush to rinse the deposited salts out, Dry to evaporate the water in the plant, Cure to break down chlorophyll and convert the starches into sugars. Sugar is sweet right?

I meant to say starches break down into sugars, not the other way around, I am out of it today. Meds must be working good tonight, lol

[PadroPadro]

Flushing...listen to Nike and BG...just DO IT.

[MI Compassion]

Flushing...listen to Nike and BG...just DO IT.

 

I happen to disagree, I have found properly dried and cured meds to be equally good whether they where flushed or not, and flusing your plant in late flower is very stressful to the plant and can negatively effect the potency and final yield. Did you read my post on page one of this thread? If so you should and research the information presented in my post.

 

Also check out this thread here:

http://www.420magazine.com/forums/how-grow-marijuana/71685-critical-look-preharvest-flushing.html

 

The only circumstance I can see where pre-harvest flushing would be beneficial is in the case of inexperienced growers who do not properly slow dry their cannabis over a 1-2 week period of time, or who do properly cure their dried cannabis for an additional 1-2 weeks MINIMUM. If the drying and curing process is done correctly the finished product will be more potent, have a much smoother and pleasant taste, and be far less harsh... and it makes no difference whatsoever if the plants where flushed prior to harvesting or not.

 

Flushing can be important in some situations to flush excess salts built up in the medium if your plant starts showing signs of nutrient lockout, but in any other circumstance it actually stresses the plant unnecessarily.

[MI Compassion]

Also, proper trimming of excess leaves will do much more for the taste in the final product than any amount of pre-harvest flushing will do, as much of the bad taste is created by chlorophyll that's in the leaves. Though the longer you cure your cannabis for the less of a factor this is as the chlorophyll breaks down during the curing process (which is why the leaves lose their green color the longer they are cured).

[Grow Thread]

flusing your plant in late flower is very stressful to the plant and can negatively effect the potency and final yield.

 

wrong

and the debate continues.

 

in general, cannabis will not pack on weight in the last days of life. period. by this time, the plant KNOWS its life is nearly over and may produce more trichomes on the already formed buds in an attempt to catch a pollen spore. afterall............ nobody can argue that the #1 goal of a female cannabis plant is to keep the lineage going..... and it can grow more trics quicker than more buds in those final days.... so it does.

 

if you get any added weight in the final week of floweing, it will normally be a squirly tail here or there and not worth it......... even in pristine conditions. the last week or 2 is not for weight gain. science. fact.

 

and, you are wrong, but correct in assuming that flushing may/may not stress the plant. if it does....... as stated, it will stress the plant into growing more trichs to possibly........... hopefully catch one male spore........ no chance of a plant turning hermie and producing seeds in 10 days time just can't happen. seeds take longer to produce. and the buds are already grown.... so you cant deplete yield.

[MI Compassion]

wrong

and the debate continues.

 

in general, cannabis will not pack on weight in the last days of life. period. by this time, the plant KNOWS its life is nearly over and may produce more trichomes on the already formed buds in an attempt to catch a pollen spore. afterall............ nobody can argue that the #1 goal of a female cannabis plant is to keep the lineage going..... and it can grow more trics quicker than more buds in those final days.... so it does.

 

if you get any added weight in the final week of floweing, it will normally be a squirly tail here or there and not worth it......... even in pristine conditions. the last week or 2 is not for weight gain. science. fact.

 

and, you are wrong, but correct in assuming that flushing may/may not stress the plant. if it does....... as stated, it will stress the plant into growing more trichs to possibly........... hopefully catch one male spore........ no chance of a plant turning hermie and producing seeds in 10 days time just can't happen. seeds take longer to produce. and the buds are already grown.... so you cant deplete yield.

 

Perhaps I should have said that I have heard it argued that flushing can decrease yield or effect potency, as I have never seen proof of either claim myself. However I have personally ran many side by side comparisons and experimented with starting flushing at different times as well as not flushing. What I found is after proper drying and curing myself nor none of my patients could tell any difference whatsoever between the flushed and not flushed plants, and the plants that where not flushed where much more healthy looking at harvest time, and not just color wise.

 

Though I don't see any problem with pre-harvest flushing, as the end result once properly dried and cured is indistinguishable it's also something I would consider very optional unless you plan on distributing meds before they are properly dried and cured - which I really hope no one that considers themselves a caregiver would ever do to any patient.

[Grow Thread]

Perhaps I should have said that I have heard it argued that flushing can decrease yield or effect potency, as I have never seen proof of either claim myself. However I have personally ran many side by side comparisons and experimented with starting flushing at different times as well as not flushing. What I found is after proper drying and curing myself nor none of my patients could tell any difference whatsoever between the flushed and not flushed plants, and the plants that where not flushed where much more healthy looking at harvest time, and not just color wise.

 

Though I don't see any problem with pre-harvest flushing, as the end result once properly dried and cured is indistinguishable it's also something I would consider very optional unless you plan on distributing meds before they are properly dried and cured - which I really hope no one that considers themselves a caregiver would ever do to any patient.

ok, you seem more than intelligent? (have to have fun right? ) i mean that in a good way.

 

 

so you would then agree that the less starches/sugars/chlorophyll in the harvested plant that need to be broken down during curing, the faster a plant reaches "that point" of the cure process that the grower desires??

 

no?

 

and flushing reduces that amount.

[MI Compassion]

ok, you seem more than intelligent? (have to have fun right? ) i mean that in a good way.

 

 

so you would then agree that the less starches/sugars/chlorophyll in the harvested plant that need to be broken down during curing, the faster a plant reaches "that point" of the cure process that the grower desires??

 

no?

 

and flushing reduces that amount.

 

Yes, that is definitely correct in theory and you would think it could help things along a bit. However I have learned with working with cannabis over the years that it's just not one of those things you want to try and hurry if you want to get the best possible results. This is the reason why I dry plants whole, in a cool dark 40-50% humidty room with very little airflow (other than a 300cfm exhaust and passive intake to prevent mold). It takes 10-14 days to dry in this manner, and takes longer to manicure the buds, but the end result is a plant that is much more evenly dried. My goal is create an environment where it takes as long as possible for the plant to dry as I find that trichome production and maturation continues during the drying phase as the plant processes continue for a number of days. If your focus is on speed or production then flushing could very well cut a couple days off of the amount of time it takes to have a harvest ready for sale, but my preference is to let the natural processes to occur.

 

My theory is that mother nature knows best... how do you flush a 14 foot tall bush that's growing in the ground outside?

 

After a couple weeks of curing there will be no distinguishable difference in the final product, and this should be the absolute minimum that you should cure your product anyways to ensure all the sugars and starches are broken down so your medicine reaches it's most potent, especially when growing cannabis of high enough quality to be considered "medicinal" (I mean real medicinal, not the low quality mids that most caregivers try to pass off as medicinal)

 

But to each their own, I always say the BEST method is what works best for the grower.

[Danxy]

From my experience and knowledge, most people overfeed their plants with nutrients and supplements and additives. This is why a flush is needed, especially withy chelated (read chemical) fertilizers. If you were to run low ppms of nutrients you may not notice a difference in flavor,or cure; however why would you not want the cleanest medicinal product possible???? I know of several growers who put organics mixed directly into their soil and those that err on the side of more is better have products that do not have the taste and purity in their product as others who use less and flush. I personally feel that alot of people do not flush because of the greed factor, they feel that if they feed till the end they will get more yield. I will sacrifice yield anyday for quality, but hey this is all just my humble opinion based in personal experience and taste. I can tell a fox farm users product anyday flush or not as it seems to leave a particular taste, as does a molasses or a sweet product users product. The best cannabis in my humble opinion is not overfed and proper flushed at the end. If you want a superior tasting product with an untouchable taste flush them girleys out.

[GanjaWarrior]

yes it is a good idea to let a plant dry out b4 harvest.... excess water in the plant when it dies.... tends to lead to mold