Growing cannabis in an old goat pen is a great idea!
How long was it a goat pen and how long since goats have been there? How much crap are we talking about here?
Goat manure is not considered “hot” the same way chicken or cow manure is and may be used right away, without composting. It also has ample amounts of macro/micro nutrients to sustain cannabis plants throughout their life cycle. There’s enough sulfur in their droppings that it shouldn’t need to be amended… especially if there were goats in that pen for a few years. Soil has natural buffers in it, so pH issues should not be a problem.
When I was growing up, we had a small family farm and raised many different types of animals for food… goats were one of them. We drank goats milk too… it’s much better than cows milk.
Anyway, when I was around 17/18 years old, we weren’t raising goats any longer, so I planted some brickweed bagseeds in a secluded corner of the goat pen and waited for them to germinate.
Once the seedlings emerged, all I had to do was water them, I never had to fertilize them or amend them with anything… just water and they grew into huge Christmas tree looking plants in no time. They averaged about 12’-13’ tall and just as wide.
The harvest was large and kept me in weed for close to a year. It looked, tasted and worked much better than the seeded brick I got the seeds from.
This will be an easy grow for you!