All you need to know about how to feed in Coco


Well-Known Member
Hi 420 !

As much as possible, I like to spend my time on here helping out new coco/hydro growers.

I started out like those guys and someone spoon fed me untill I was a big boy and could handle reading a number on a stick.

I'm finding myself spending my limited time here on the wrong things though and I've finally worked out how to work my "Sig"

So here is the first of a few threads that I'll add to my Sig In order to allow me to spend my time here more productively.....

This is a tried and tested, 100% full proof way to hand feed plants in coco.
Just follow a few simple rules and all will go perfectly.

13 words is all you need to know.

Feed quarter strength nutes at the right ph as often as you can.

That's it in a nutshell. 13 words.

This sounds a bit crazy but here's why that's all you need to know....
Wouldn't be science if I didn't back it up with some techno jargon and numbers now would it :)

Coco is effectively just an empty sponge.
It doesn't do anything.
Just provides something for your roots to grow in.
Coco doesn't buffer ph levels or breakdown solids into nutrient form like soil does.
It's just an empty sponge.
It abides by the same rules as DWC, NFT, ebb&flo and every other hydro method.

There are brands of coco that come preloaded with nutrients but I can't recomend strongly enough to avoid them.

For best results you really want to be watering this stuff as much as possible.
Having anything in slow release form is a bad idea because the more you water, the stronger it will get.

Due to the volume of water going through it you're also best to use around 30% perilite mixed in with the coco.
By doing this you will increase the drainage capabilities of the media.
That means you're increasing the amount of oxygen available to the roots.
And that my friends means your plants can't drown!

Let's just clarify that one too.
There is no such thing as giving too much water to a cannabis plant.
Otherwise DWC wouldn't exist would It??

The problems people get from feeding high volumes come from a lack of oxygen. Nothing else.
There are various reasons behind it but the actual problem is the lack of O2.

In a 70/30 coco/perilite mix, you can feed as much as you want and it will just run right through it, bringing more and more oxygen to the roots every time you try to drown them.

This is also why we only need to feed quarter strength nutes.
The extra oxygen from the Increased watering rates and awesome aeration of the media means the nutrients are more readily available for the plant to absorb them.

(Tbc tomorrow. Night time now. )
Now quarter strength is a pretty vague sounding term but you generally find that the full strength recommended by most nute companies is 1600-2000ppm. So by going quarter strength, even without a ppm meter it's safe to say you should be around 350-500ppm or 0.7-1.0 If your meter reads In ec aswell.

It's a pretty magical number range. Should be just on the line where it doesnt fry a seedling but can also fully power a plant that gets to about 5oz.

If you do have a ppm pen then 200ppm for the first 2 weeks.
Then 300 for 2-3 weeks.
when the bottoms start going yellow up it to 450ppm.

These numbers are not including your tap water and if you're using ro water you'll need to add on some extra for calmag.

Keep Shit Simple Too!
None of this 14 different bottles for the grow. It's a load of useless, confusing, snake oil.
Lots of things are obviously beneficial if they're used correctly but worry about fine tuning once you can grow a basic run.

All you need for seedlings is a tiny amount of veg nutes. That's it.
If that's all you give them they'll be happy as Larry.
All you need for the first few weeks is a tiny amount of veg nutes and if you want to you can just get a 1 part veg nute and nothing else other than a 1 part bloom nute, a PK booster and a bottle of calmag+ just In case.
That will do you a perfect grow no worries.

There are additives and things we can add to boost the plant in whichever way we need to.

For the roots, if you use a root boost of some sort they will grow better.
Some people use beneficial bacterial products like hydroguard.
Others like myself prefer to use bottled root boost and a product like sm-90 to kill all bacteria which helps the roots stay healthy that way .

Liquid scillica is probably the most useful extra in my opinion that you can give to a plant in veg.
Can't rate it highly enough.
Use it at 30-50ppm and it turns your plants to rubber. Makes them much more flexible, much stronger, helps them deal with environmental stress and the skin grows thicker so certain bugs can have a hard time causing as much damage.

It basically reinforces the cell walls as the plant grows. A bit like pouring water into a box of marbles. It fills in all the gaps in the structure.
It's really alkaline and it burns your skin though so be careful with it. Also, I haven't tried it but it probably reacts quite badly with the ph down liquid you'll need to adjust the ph back once you add it.
I'll cover ph in a bit though.

Bed time for me again. I'll get this done though. :)
What kind of yields do you et with your methods?
I'm growing in 10L fabric pots mostly mate. Get an average of 3 - 4oz per plant based on 6 plants sharing a 660w hps.
If your plan is to grow less plants but bigger then you just add on 50% nutes every time the bottoms go yellow.

See how I said" 200ppm-300ppm-450ppm for those with a ppm meter."
It's 50% rise every time if the bottom leaves yellow.
That pretty much garuntees you can't ever get any tox problems.
That in turn mean your ph will stay in range for as long as it possibly can.

If the mids still lose colour and go blotchy or rusty they need extra calmag.
Tops go yellow it's iron def. For which you need iether a bottle of 'Micro' or do what I do and by calmag+ which has iron too. That's all I use it for, my nutes have enough calmag already.

That's about the limit of how big you can go on 450ppm / ec 0.9.
Blue dream'matic from fastbuds. Sure that was the biggest one that time at bang on 4oz.
3 of them and 3 brooklynne sunrise autos that time. Wouldn't grow the b/s again though. Total cabbage.
The blue dream though is probably my favourite stone in 15 years :)
Your plants look great! I grow in coco and yield over a pound per plant under 600 watts of COB led. I feed what the nutrient manufacture recommends ( Canna Nutes A&B with some silicon and PK boost near the end of flower ) once a day with 20% runoff
Yeah my pounders need around full strength too. Profile pic was smashing 1400ppm no problem.
Not many people do that though.
Especially people that are searching for how to feed lol so didnt think it worth while to include that sort of detail.
It's generally assumed that most people will be doing 4-6 plants per meter. 3-5oz sort of vibe so i just went for that.
I'll be doing 2 show off plants at some point shortly though so it'll all be included in my soon to be
"How to pull a 1lb auto" thread.
Can't wait to get that one fired up.
This is a great thread. Growing in coco is really easy, canna A &B + calmag is all you need. I am on my 8th grow & have never owned a ppm meter. Just flood them till I see runoff. If I see any problems I flush them with ph water & then feed them again.
Thanks buddy. Yeah it really is a doddle in coco. Too many people try to over complicate it and the truth is you just feed week and often and you don't need to known the rest cos it doesn't go wrong.

I only figured the ppm thing out as I learned to grow in a reservoir. When I grow in just coco I don't bother with the ppm pen. I know close enough what it is anyway.

I've used the canna nutes years ago on my first run. Was growing for a mate and just done what he said and never googled anything. Only gave it a&b though. No calmag.
I'm using growth technology now and they're awesome so far. This is the first run with just them though so we'll see how they turn out.
This pic is from my current grow. After I flipped them I decided to try what you suggested, I was not going to increase nute strength until it started pulling food from the leaf to show me it wanted more. I just figured it was better to let the plant tell me what it wants vs a chart telling me what it needs. It did not slow them down any up top.

This pic is from my current grow. After I flipped them I decided to try what you suggested, I was not going to increase nute strength until it started pulling food from the leaf to show me it wanted more. I just figured it was better to let the plant tell me what it wants vs a chart telling me what it needs. It did not slow them down any up top.

Thanks for sharing buddy:)
It's the easiest way to do things imo. The bottom leaves all come off one way or another anyway so might as well get some use out of them. As long as you're paying attention it'll never cause any damage. It's always easier to add something in than it is to take it back out if it's too much :)
Had perfect timing there too Mr Sherlock.
That's what happens when the bottoms go yellow.
I mentioned another deficit that can happen in late veg.
Tops going yellow which is iron def that I use calmag+ to fix. Well its day 2 of 12/12 and bang on time. Iron def. Not to worry though thats just my cue start using the calmag+(ca,mg,fe&n) at quarter strength and it'll go away in a day or 2 :)

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