When to flush?

Flush it the last 2 weeks before harvest. You can also micro dose molasses in the water you will be using to flush because it can potentially encourage beneficial microbes for healthier soil and more efficient nutrient intake. The genetics will be whatever its supposed to be in the end so just don't try to rush the process.

Hi they look like they need at least another 4 weeks yet also I'd check for seeds looks pollinated

It depends on what you want really. If you want trichomes mostly amber wait to flush until you see amber on the sugar leaves. If you want mostly cloudy start flushing when you see that they are grown, what I mean by grown is tall and defined with the mushroomy head on the top but all clear. Hope that makes sense good luck

Just switch to plain water when the flowers have 90-95% brown pistils and harvest when they have have 95-98% brown pistils, this will put you in the 10-30% amber trichomes zone and is the easiest method for determining harvest. Besides, no one I know can accurately determine 17% or 11% or 23% amber trichomes! Also, not all plants get ambe trichomes anyway. No need to drown your plants either, just give normal amounts of plain water at normal watering schedules, there is no need to flood anything or do a toilet impersonation, just with-hold nutrients for the final 7-10 days before harvest, this is all that is required. Flushing with gallons and gallons of water does not make cleaner buds, but it does cause hyper hydrated buds, which can lead to problems when drying, like bud rot. Flushing should really be re-named "nutrient witholding period". After growing for some time, you will get to the stage of experience where you will "just know" when it is harvest time. Try not to feel any pressure into getting everything 100% perfectly right, experience is a teacher, mainly as to not do the same errors again and not so much as to what is the "right" thing to do, but what not to do! Hope this helps, Organoman.

i'm a big fan of the courtesy flush. So, shortly after pinching a loaf. 4 weeks in, so you got forever and a day left to read up on this from many sources. as long as you aren't bombing it with ferts + hot soil or a hydro/soilles equivalent context with an extremely high EC for no reason, there is no reason to flush. Flushing's supposed benefits are not backed up by credible research - never were. When they analyze buds with or without flush, there are no more additional minerals or buildup in the buds nor any concentration differences than normal variance. Blind taste tests also fail to resolve any difference. in fact one such study showed a statistically significant preference (i.e. discernable from normal volatility) to the unflushed buds, but it was a very small difference. These are claims made by those that support flushing... These things are objectively untrue. If there are other reasons, this at least should make you question the integrity of any other claims. cells that make up buds do not store things in bulk like adipose tissue in animals. Their function involves sexual reproduction and not storage facilities for the plant. maybe, if it's overcooked? might be a good idea to flush? There may be some context in which it is beneficial, but such a thing needs to be proven before being confident about it Flushing is a tool for when things are going very very wrong in your medium. It should always be a last-ditch effort or at least very far down the list of reactions to a problem. if ratio of nutes or pH are way off, flushing is a great tool to reset the medium to insignificant levels before properly fertilizing in correct ratios and concentrations at a given pH range. (some adjustments needed relative to groing methods... e.g. hydro doesn't need a flush at all.. just a rez change will accomplish same thing.) it almost always costs you somethng if flushed with just-water... plant will grow more slowly than otherwise would have for a time, ceteris paribus. The benefit must outwieght this loss. If you just don't want to mix ferts, you can let the plant pull the 'fat' from the leaves. This involves more work from the plant, almost certainly, so likely a slightly slower metabolic rate than more readily available nutes from roots.. but, the consequences are going to be insignificant that last week or so. I usually don't bother the last 2-3 irrigatons, but only because i am lazy. i don't believe it does anything special, and if anything costs an insignifant % of yield. (*only if my rez empty, too) Soapbox time! -- you can skip this. Think about a plant growing outside in fertile soil that grows amazing plants... the best outdoor in the world, wherever it may be... Those buds come out fine with no flush, and there's no reasonable way to flush the earth... no reasonable person is wasting tens of thousands of gallons of fwater on a field in an effort to leech out most or all the nutrients, therefore ruining the land for at least the near future, BWAHAH. holy shit the erosion it'd cause.. be the dust bowl all over again and caused by similar reasons - clinging to outdated farming techniques when the knowledge exists to do better. The dust bowl was caused by the pure ignorance of farmers refusing to change with new and better knowledge. They prefered "what daddy did," and that's not very sophisticated, is it? when something is proven to be untrue, egos often get in the way of facts. The onus is on the ones claiming something to be true to prove it, which never happened in the first place - big red flag! So far, the research does not support these reasons (mineral concentration in buds and taste) for flushing before harvest. and yes, we absolutely can determine the molecular makeup and relative proportions of samples from a plant with existing technology. Some people seem to think this is the 1800s at times. Comparing it to a control group would illuminate the nonsense that flushing-before-harvest is, assuming sufficient sample sizes used. Heck, it won't be long until we can crispr method exact terpene profiles and excellent thc production... you want red flowers? sure why tf not? no different than breeding to get specific traits by working backward from expected ratios phenotypes based on number of alleles invovled etc.. but a hell of a lot faster! Can always design them to be sterile to protect wild populations and gene pool as whole. Frankenstein weed... can't wait. DNA is just 1's and 0's (before contradicting, go look how it is "unzipped" and read.. 1's and 0's in a finite number of combinations... not special in any way, ever, whether cripr'd or bred, same outcome... a rose is a rose... it ain't magic. :P)

Got to agree with @grey_wolf here, each plant will have its own time when its ready. Autos can vary a lot depending if they get shocked. So trichomes are a great indicator. As for flushing. If you want to do it. 5 days before u plan on chopping in hydro is good. I myself do not flush, but my growing style and medium holds onto way to much water to do it right. In hydro its a useful tool is salts build up and cause some lockouts even before harvest, some people do it when switching from grow to flower. Best Of Luck!

@Ganjawiththewind Okay so you really want to be monitoring the trichomes for ripeness see https://www.alchimiaweb.com/blogen/harvest-marijuana-plants-trichome-ripeness/ get yourself a jewellers loupe they are fairly cheap on amazon or ebay etc generally I think two weeks is overkill for any flushing keep the feeds up until one week before you intend to chop then just use plain water and on the harvest day itself... chop the plant straight after a dark period . ie lights off Happy harvesting mate