none of the ingredients supply nutrients in any appreciable amount. Generally speaking when growing in containers you are dependent upon added fertilizers. I add Nutricote Controlled Release Fertilizer at a rate of 1# Nitrogen/cuyd medium and then irrigate with a water soluble fertilizer at a concentration of between 50-100 ppm nitrogen depending on species.

+1

I use Dyna Grow - Foliage Pro, because it has all the macro and micro nutrients.

This is very confusing to me as I'm a new user of gritty mix. Can you please explain how you apply it? Thank you

The controlled release fertilizer is in the form of resin pellets. These get mixed into the container medium. The water soluble just gets dissolved into the irrigation water.

Gardengal48 - I've prepared gritty mix ingredients. Should I add the osmocote now after soaking the pine fines in water? Then fertilize monthly? Thanks

I forget what Al's recipe calls for as I tend to do it by rote now, but I just add a scant handful or so (depends on the container size) to the backfill soil after seating the plant in the container. I don't mix it into the whole potting mix as most of my containers are quite large and there is no need to fertilize soil below where the plant roots are seated. Or you can just topdress with the CRF after planting. I do it both ways :-)