Is horse compost ok to start Marijauna plants in? I just came across ALOTTTTTTTT of it lol.....my friend that does landscaping has like PILES of it and he does not use it anymore because he stopped doing gardens and shit he said as long as I shovel it I can have it.

So my questions are, he said the flowers and asparagus he started in it grew faster and stronger then in Miracle Grow or any other Potting Soil....is this the same with marijuana?

Does it have enough nutrients to feed the plants through the cycle?
How deep does my Outdoor hole need to be?
I dug each one about 1 foot deep and started to hit clay....