How much you add, depends on How Many Gallons of Soil/Medium.
This is what I would do.
Late flower phase, sativa plants: if you have a sativa plant chances are they may need an additional weeks of growing time so you could do a light top dress 2tbsp of 100% Power Bloom 2-8-4 per gallon of medium eg. 10tbsp of 100% Power Bloom 2-8-4 for a 5 gallon container
-harvest-
I vary the very first step slightly.
I use
Promix BX, as my medium, and I supplement right off the bat with
Gaia Green 4-4-4 at a rate of 2 LEVEL TSP in an 18oz Solo Cup, and 1/2 TSP of Azomite.
Epsom Salts at 1 TSP Gallon-Reverse Osmosis water. Use every watering.
I think I may have copied this and saved it, from this site, but cant remember. But it is a very good guide.
Sprout phase, ~1 week: NO nutrients are being added to the growing medium. Earth worm castings & cotyledons provide more than enough nutrition for the first 2 weeks of a seeds life
-transplant to 1gallon-
Early veg phase, 4 weeks: amend 3tbsp of 100% All Purpose 4-4-4 per gallon of medium eg. 3tbsp of 4-4-4 for a 1gallon container
Late veg phase if needed, 4 weeks: top dress 3tbsp of 100% All Purpose 4-4-4 per gallon of medium eg. 3tbsp of 4-4-4 for a 1 gallon container
-transplant to 5gallon-
Early flower phase, 1 week before flipping lights: amend 3tbsp of 50% All Purpose 4-4-4 and 50% Power Bloom 2-8-4 per gallon of medium eg. 8tbsp of 4-4-4 and 8tbsp of 2-8-4 for a 5gallon container
Mid flower phase, week 3 or 4 of flower: top dress 3tbsp of 25% All Purpose 4-4-4 and 75% Power Bloom 2-8-4 per gallon of medium eg. 4tbsp of 4-4-4 and 12tbsp of 2-8-4 for a 5 gallon container
Late flower phase, sativa plants: if you have a sativa plant chances are they may need an additional weeks of growing time so you could do a light top dress 2tbsp of 100% Power Bloom 2-8-4 per gallon of medium eg. 10tbsp of 100% Power Bloom 2-8-4 for a 5gallon container
-harvest-
