While I use Promix BX, and water by hand,. When I use chemicals, I use Master Blend 4-18-38-15.55-0-0 Calcium Nitrate- Epsom Salts. I start off right of the bat, with Seedlings at about 10% of recommended full dose, and slowly, over the weeks, increase the amount I am giving them.
In Veg, I usually never go over 25%-30% of recommended feeding, unless they show signs of deficiency. Nothing is foolproof, and one should keep constant watch, and see how the plant(s) react to the feed/waterings. In a perfect situation, you should see some sort of growth, or reaction to feeding/watering, every time they are fed/watered. I feed, at every watering.
In flowering, I will increase dose of the Base Nutrients until about 40%-50% of recommended feeding, and in weeks 4-6, in an 8 weeks flowering strain, I will increase Epsom Salts by another 10% of Recommended dose. So Epsom Salts goes as high as 60% of recommended max dose, in weeks 4-6, and it is slowly increased to this number, by only several percentages per week, until week 6, the last week, it is getting the full 60%.
Then weeks 7-8, nutrients are cut by 25% in week 7, and another 25%, in week 8.
I do not use any different Flowering/Veg NPK ratio changes. Only increase PPM, of ALL Nutrients, until week 6, in an 8 Weeks Flowering strain. Make adjustments if Longer/Shorter.
It is true, too much Nitrogen, is not a good thing, and can cause delayed flowering, more leaf ect. Its all about ratio.
It makes ZERO sense, to cut out Nitrogen, when the plant, is going to grow, the most it ever has, produce more chemicals, and hormones than it ever has. You cannot ask a plant to do this, whilst cutting out Nitrogen. Nitrogen is responsible for every metabolic process, including cell division/mitosis. While Nitrogen, is not a Protein, it is a key component, of Protein. Nitrogen, is essential, for building the stricture, of Proteins, and is crucial for many metabolic functions of life.
Would you think a Bodybuilder, or any athlete trying to achieve maximum physical development, and stamina, would cut out Protein, in the most critical part of their training stage? When humans eat Protein, our bodies turn it into Nitrogen. Athletes try and maintain an Anabolic State, which means to Build Up. They try and maintain a Positive Nitrogen Balance. Anabolic State- The anthesis of trying to build muscle, is being Catabolic, which is what is happening, when plant leaves start turning yellow, from the bottom up. The plant, is cannibalizing itself, by using the leaves, as Nitrogen source.
Protein, is Greek for. Of First Importance. Of all the Macro Nutrients, Protein, is the most important, as was stated. It is responsible for every metabolic process. Nitrogen, is essential for building the structure, of proteins. Dont cut it out in flowering. Just correct the ratio.
For Long Flowering Sativas,- 12+ weeks. I would cut the 15.5-0-0 back by 50%, after 4 weeks of flowering, and in many varieties, dont require as many PPM, as modern hybrids. I always try and use the least amount of fertilizer, to keep them growing as fast as possible. I never try and force feed them.
After all that, and while I have mainly used chemicals. I find the Gaia Green 4-4-4, and the 2-8-4, so simple to use, it basically takes all the guess work out of trying to figure all the other stuff out.
Only thing to worry about is Water/Medium- PH.
Start out with 4-4-4 only. 2-3 TBLSP per Gallon Medium. 3 TBLSP is full dose. I use 3 TBLSP.
I also use AZOMITE-1 TBLSP per Gallon Medium.
After a month either replenish with more 4-4-4, or use half the amount of 4-4-4, and add the other half as 2-8-4, for flowering. Also add 1 TSP AZOMITE Per Gallon Soil.
If flowering, best to wait 1 week after combining 4-4-4 x 2-8-4, before cutting lights back. Then 3 WEEKS later, add more 4-4-4 x 2-8-4. If flowering longer than 70 days, use only 2-8-4 and 3 TBLSP gallon soil. No more 4-4-4. Use Azomite every 30 days. 1 TSP Gallon Soil.
