Flushing to prevent nutrient lockout

Hey all quick question

I've seen people casually mentioned flushing with neutral pH water before switching to flowering. In my previous grows I think I suffered from nutrient lockout during the flowering periods because I always gave my plants nutrients, never gave it any normal water. On my current grow I've been consistently increasing the nutrient dosage throughout my plants life, ppm is over 1100 after I mix all my nutrients now.
But I'm about to switch to 12/12 in a few days and I'm wondering how much water I should flush each plant with? I don't want to over-do it and stress the plants with overwatering.
I'm growing in 5 gallon buckets with plenty of drainage holes. Medium is a soil/perlite/peat moss blend but it retains a lot of water. I feed each plant 1 gallon of water currently, would 2 gallons of plain neutral water be enough to flush each of the plants? Or should I just do one gallon for each plant? I read someone say to properly flush a plant you should feed it twice the amount of your growing medium... So in my case that would be 10 gallons. I feel like that would really stress the plants. Any ideas?

That is the norm (twice the amount of your pot size) and it should be fine tho it does stress them a bit and packs the medium but if your concerned of over feeding give it a go. Next grow you could stop the feed and just give them straight PH'd water a week or two before flower so they use up some excess nutes in the soil same goes for harvest.
Cheers!

Thanks. I'm gonna flood each plant with 10 gallons and see how they react. After reading the thread about my line of nutrients (nectar of the gods) I realize I should be flushing pretty frequently...

DoubleX5150 said:

Thanks. I'm gonna flood each plant with 10 gallons and see how they react. After reading the thread about my line of nutrients (nectar of the gods) I realize I should be flushing pretty frequently...

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Nuts. They need a transition feed and after that bloom feeds.

I wouldn't flush it unless it was sick or had a problem, doesn't matter if I'm changing it to flower or not. Why would you want to do that, you're just setting a healthy plant back?

Beachwalker said:

I wouldn't flush it unless it was sick or had a problem, doesn't matter if I'm changing it to flower or not. Why would you want to do that, you're just setting a healthy plant back?

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Too many guys just starting like to screw with stuff. I mean why mess with a plant when it’s good I’ll never understand this concept lol.

1100 ppm is way too much fertilizer especially if fed every watering. I use a max of 600ppm (1.2ec) usually lower for plants that produce even 6oz indoors under 600w hps.

And the only time i leach my pots with extra water is if there is nutrient related leaf stress. 20% runoff each watering usually is enough to clear excess.

Beachwalker said:

I wouldn't flush it unless it was sick or had a problem, doesn't matter if I'm changing it to flower or not. Why would you want to do that, you're just setting a healthy plant back?

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Because based on my last grow, I think I had a nitrogen lockout. I was feeding non-stop and never gave it pure water. My yield suffered and I ended up with light fluffy buds.

MichiganMedGrower said:

1100 ppm is way too much fertilizer especially if fed every watering. I use a max of 600ppm (1.2ec) usually lower for plants that produce even 6oz indoors under 600w hps.

And the only time i leach my pots with extra water is if there is nutrient related leaf stress. 20% runoff each watering usually is enough to clear excess.

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Why do you think 1110 ppm is too high? Keep in mind this is the reading of my nutrients+water, and when checking the run off it goes down to 200-250ppm, so I know the plants are absorbing them.

But this is not last grow, it's this grow and my point is you don't want to flush a healthy plant because of your last grow ?? I don't mean this in a bad way but I don't get your logic but whatever you decide good luck!

And btw the proper way to flush is 3x the volume of the pot, not 2

DoubleX5150 said:

Because based on my last grow, I think I had a nitrogen lockout. I was feeding non-stop and never gave it pure water. My yield suffered and I ended up with light fluffy buds.

Why do you think 1110 ppm is too high? Keep in mind this is the reading of my nutrients+water, and when checking the run off it goes down to 200-250ppm, so I know the plants are absorbing them.

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You only know your medium is absorbing them. And salts attract salts.

However,

The plants will take up as much as you give them. Whether they burn or not is more strain and environment dependent.

Your description of fluffy buds may be simply from overfeeding.

This plant is pretty big and has been fed max 1.0ec (500ppm) Tapered up from a light dose fed every time since the soil in the final pot was depleted of nutrients.

Now she is being tapered down as she ripens and needs less.

I have found lighter doses each feeding produces best results.

DoubleX5150 said:

Because based on my last grow, I think I had a nitrogen lockout. I was feeding non-stop and never gave it pure water. My yield suffered and I ended up with light fluffy buds.

Why do you think 1110 ppm is too high? Keep in mind this is the reading of my nutrients+water, and when checking the run off it goes down to 200-250ppm, so I know the plants are absorbing them.

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So you think your plant is sucking 800ppm from the nutrient solution during watering? Man those babies must be thirsty!

Soil runoff measurement is next to useless and I would never draw any conclusions from it...that is if I measured it, which I don't.
JD

JohnDee said:

So you think your plant is sucking 800ppm from the nutrient solution during watering? Man those babies must be thirsty!

Soil runoff measurement is next to useless and I would never draw any conclusions from it...that is if I measured it, which I don't.
JD

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Measuring runoff in potting soil may not be accurate like in hydro but it does show trends if done regularly.

Oddly i have noticed that when the runoff is much lower than the input the medium is likely accumulating rather than releasing excess nutrients amd minerals. With my well water, although pretty soft, this usualy meams calcium and iron are going to start clogging roots.

MichiganMedGrower said:

Measuring runoff in potting soil may not be accurate like in hydro but it does show trends if done regularly.

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I can see where this might be useful. So the exact number is less significant then the rise or fall of the readings.

Very occasionally I've seen coco growers report a dramatic drop in runoff compared to input water. I figured it may have been CEC related and the coco was binding nutrient elements as they pass through. Just a theory...and not at all sure if that theory could be applied to soil.
JD

MichiganMedGrower said:

Measuring runoff in potting soil may not be accurate like in hydro but it does show trends if done regularly.

Oddly i have noticed that when the runoff is much lower than the input the medium is likely accumulating rather than releasing excess nutrients amd minerals. With my well water, although pretty soft, this usualy meams calcium and iron are going to start clogging roots.

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So in this case, would flushing be beneficial? Assuming my nutrients are just getting stuck in the medium, which is likely considering I screwed up the proportions of my soil, I needed more perlite because the drainage isn't as smooth as I'd like it to me. But the nutrient buildup is what I was concerned about. I'm worried that once I flip to flowering my buds wont get big because of the massive amounts of N and P that I've been feeding.

DoubleX5150 said:

So in this case, would flushing be beneficial? Assuming my nutrients are just getting stuck in the medium, which is likely considering I screwed up the proportions of my soil, I needed more perlite because the drainage isn't as smooth as I'd like it to me. But the nutrient buildup is what I was concerned about. I'm worried that once I flip to flowering my buds wont get big because of the massive amounts of N and P that I've been feeding.

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Are the plants stressed from the nutrients? Maybe water only until you see more nutes needed?

Where plant numbers allow, I float and dip my coco coir pots or bags in a bucket, just larger.
If pots are hot, it would have a dilute strength feed in. I measure the water after dipping, and if it doesn't go up too much in ppm I just top it up and dip the next larger plant's pot.

MichiganMedGrower said:

Measuring runoff in potting soil may not be accurate like in hydro but it does show trends if done regularly.

Oddly i have noticed that when the runoff is much lower than the input the medium is likely accumulating rather than releasing excess nutrients amd minerals. With my well water, although pretty soft, this usualy meams calcium and iron are going to start clogging roots.

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Welcome Back!

Can you expand on the situation when your runoff was lower than the input.
I have never experience it testing my runoff in soil.
Was the soil fresh or in use for a while?
What where the ppms going in and coming out?
Is it something new to you or has this happened often?

I'm curious because I use runoff as a tool to monitor build up in my soil that has been re amended for several years.

Update: I flushed each plant with 3 gallons of neutral water and the run off came out pretty clean.
Also built my first scrog net and set it up. Switching to 12/12 by next friday, just waiting for some flowering nutes to get delivered to my boys at the grow store.

ya thats odd that run off is lower.

DoubleX5150 said:

Update: I flushed each plant with 3 gallons of neutral water and the run off came out pretty clean.
Also built my first scrog net and set it up. Switching to 12/12 by next friday, just waiting for some flowering nutes to get delivered to my boys at the grow store.

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Lol you just couldn’t help but run a bunch of water through them.