When it comes to mixing nutrients should I go off PPM or manufacturers label?

Tap4942

Member
I'm currently in veg with plants ranging from week 4 to week 8. I've tried feeding full strength, half strength and at 800 ppm. I'm growing in coco.

I feed once a day at lights on but in the past I fed when the pot felt light and I feel like I had better success that way.

What is the correct way to feed? Should I feed once a day? Should I feed based on ppm or label?

Nutrients:
Advanced nutrients 3 part ph perfect micro, grow & bloom
Botanicare Silica Blast
Botanicare Cal-mag
Humboldts Secrets plant Enzymes
 
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amneziaHaze

Well-Known Member
i use different nutes but i can tell you i had in my life plants that grew with 1600 ppm and plants that grew with 800 ppm anything over would cause a burn
 

coreywebster

Well-Known Member
I'm currently in veg with plants ranging from week 4 to week 8. I've tried feeding full strength, half strength and at 800 ppm.

I feed once a day at lights on but in the past I fed when the pot felt light and I feel like I had better success that way.

What is the correct way to feed? Should I feed once a day? Should I feed based on ppm or label?

Nutrients:
Advanced nutrients 3 part ph perfect micro, grow & bloom
Botanicare Silica Blast
Botanicare Cal-mag
Humboldts Secrets plant Enzymes
What medium?
 

Tap4942

Member
i use different nutes but i can tell you i had in my life plants that grew with 1600 ppm and plants that grew with 800 ppm anything over would cause a burn
Wow that's sad to hear. I gave them half strenght and I'm hoping that will be good for everyday watering.
 

coreywebster

Well-Known Member
Coco Coir
Feed them at least once a day in veg and more in flower, don't let them dry out , give 10-20% run off and stick to about 75% of recommended nutrients dose according to their chart and you'll be good.

If you've been letting them dry out then flush them with a weak nutrient solution PHd to 5.8 -6.2 , to make sure there no built up salts
 

ec121

Well-Known Member
I'm currently in veg with plants ranging from week 4 to week 8. I've tried feeding full strength, half strength and at 800 ppm. I'm growing in coco.

I feed once a day at lights on but in the past I fed when the pot felt light and I feel like I had better success that way.

What is the correct way to feed? Should I feed once a day? Should I feed based on ppm or label?

Nutrients:
Advanced nutrients 3 part ph perfect micro, grow & bloom
Botanicare Silica Blast
Botanicare Cal-mag
Humboldts Secrets plant Enzymes

You always want to get the NER (Nutrient Element Ratio) correct. That comes from the manufacturer, so if they say something like:

5ml part A
10ml part B
5ml part C

as a recommended dose, then that ratio is 1/2/1 of parts A/B/C. That is what you want to keep consistent. If the crop you're growing takes a higher EC, then perhaps 7.5ml/15ml/7.5ml would suffice, but the ratio is still 1/2/1.

Or maybe 2.5/5/2.5 - that would still be a 1/2/1 ratio. Keeping the NER correct keeps the nutrients in balance.

PPM is just a calculation of EC, but the problem is there are 3 PPM scales: 500, 640, 700. That means that 1.0 EC will show as either 500PPM, 640PPM, or 700PPM depending on which pen you're using so simply saying PPM without disclosing which scale your pen converts EC to will lead to people making guesses or asking questions.

As for EC, depending on the nutrient line you're using, the recommendations could be too strong. For example, cannabis cultivators have used General Hydroponics for decades, but General Hydroponics is a general nutrient line for ALL crops.

This means that their suggestions of how many tsp's or ml's to give are not going to be specific to cannabis. For example, the EC for tomatoes, cucumbers, and eggplant can be as high as 5.0, and that would fry a cannabis plant right quick.

Because of this, cannabis growers have suggested 1/4 dose or 1/2 dose because General Hydroponics is not basing their doses off of cannabis; they are giving a general dose that works for a variety of crops, but the NER works for all crops.

So, all of that is to say to always go by EC or PPM when configuring your dose. That will also help when you're discussing feeds during a grow as everyone will know what 1.2 EC is but not know what the label dose of the bottle with a cartoon graphic on it means.
 

calvin.m16

Well-Known Member
There are many variables to how much fertilizer to feed. Vegetation time (how big plants are), Environment, pot size/hydro, watering frequency, strain/pheno differences. If your growing multiple strains or even different phenos of the same strain you will have to find the balance that keeps all the plants happy. If your growing 1 strain you can really fine tune things.

I always start at half what the manufacturer recommends, then adjust from there. In veg I try avoiding any tip burn but in flower I will very slowly increase the feed until I see tip burn then back it off 10-15% until no more tip burn. Plants will also require more/less fertilizer at different stages of growth. For example late flower the plant doesn't need a high EC because the plant is basically just ripening at that point.

p.s there are brands like Athena Ag that recommend 3.0 EC start to finish in veg and bloom. The problem I have with this, is I go through an assload of salts hitting these numbers. It's a lot of filler or something, I don't understand how that's possible. I run Maxigro at 1 EC in veg and MaxiBloom on average at 1.6 EC in flower. All my starting water is ~10 PPM Reverse osmosis. I never see deficiencies and I never use calmag or any other additives in coco coir.

The biggest misconception about fertilizer is that more will result in bigger growth and more yield. The truth is having a balanced feed that isn't too much or too little will get you the numbers your looking for. The feed chart is only a basic reference point, it should be used but find a nutrient/fertilizer you like using and dial it in over time for your specific conditions.

Other things I've unscientifically disproven in my basement is a specific pheno grown in super soil with tons of organic bullshit will taste and smoke the exact same as the same plant grown in inert coco with synthetic base nutrients. The additives and magic miracle supplements are all pretty much bullshit. Sure mycorrhizae can be beneficial but why the fuck do I need a microbe/fungi to help my roots take up chelated plant-available elements? I think synganic is retarded but I digress. I Just hope I save someone money from buying other products like I once did.
 
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marzig

Member
I use both EC and ppm scale 700. I use ppm to calculate how much nutrient to add when topping off my DWC buckets. The plants I'm growing now prefer an EC between 1.0 to 1.2.
 
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