How to tell when to flush

[toddtony]

I am currently in the middle of week 5 of flowering this is my first grow and I don’t have strain information because I’m growing from random seeds guessing by the leaf and stem structure I’m guessing it’s a sativa dominant hybrid

Wondering how to tell when to flush/stop feeding from what I’ve seen you should start 2 weeks before harvest I imagine this plant will be done week 8 or 9​

 

[marcus611a]

I never flush and everything's always came out all right and I feed all the way up to the end

 

[Azimuth]

Depends on why you think you need to flush I suppose. If it's included in your nute line you just follow their directions.

You can't flush nutrients out of the bud material, but you can flush the soil to reset it if the salts have built up and you're concerned about lockouts.

 

[SmokingWings]

Wondering how to tell when to flush.....

What are you growing in? Is it a natural soil, or a type of coco mix, or something else? Most importantly what are you using when fertilizing?

What Azimuth mentions below is one of the more important things to consider....

You can't flush nutrients out of the bud material, but you can flush the soil to reset it if the salts have built up and you're concerned about lockouts.

 

[zigzagman1960]

@toddtony I agree with everything posted. There’s also the confusing rule of flushing in the ‘last 2 weeks of flower’. No noob is going to get it right. I’m going to stir the pot—If you feed your plants properly all the way to the end—When the buds are swollen as big as there going to get and all the pistils have died back BUT the leaves are DARK green—you can stop feeding TO SAVE MONEY—there’s plenty nutes in those DARK green leaves for a week or two. This won’t improve your buds unless it forces you to wait till they are ripe then wait 2 more weeks—oh and that would be the time to peak at your trichomes to see what they look like after the bud shows full ripeness. As far as flushing to remove nutes from the buds—it don’t work that way

 

[KeithLemon]

Loaded question but is flushing really necessary. I never did flush last year but it was my first plant and I did not even know how to flush. I do not think everyone does it, but I will consider it this year. Must be some benefit or no one would do it.

 

[Roy Growin]

I taper off the feed and finally give plain water but that's not really 'flushing', more that the plant doesn't need much/any nutrients that late in flower so I don't provide any
Most synthetic nutrients and additives charts advise to use plain water for the last week - makes sense to me

 

[Sueet]

It all has to do with what nutrients you are using.

If you are using a system where they have the different elements together in a bottle and chelated with salt, that salt piles up in your medium as the plant removes the nutrients, so a flush can be very helpful. Most nutes that use this type of system include at least one flush in their schedule.

It also has a lot to do with exactly what you mean by flushing, as @zigzagman1960 pointed out a plant that has been well fed throughout flower can probably make the last couple weeks on what is in her leaves alone ... is it necessary? Idk, different question, personal choice I'd say on that one.

eta: I personally rather keep them fed til the end, I like to think they've got a great life for all except that very last day. But if you don't anthropomorphize your plants and would rather save a bit of money, that works too.