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.