My sixth grow this year.
Organic fertilizers....
I use wheat flour, oat meal flour,
coffee grounds, ash from campfire.
You can use wheat flour, oat meal flour with some
added water in a container for fermentation for good bacteria.
Add some in the water when watering your plants.
Cost...
Already smoked everything :D and got loads of seeds. Already have new plants growing. Might post some new pictures for this year when they are bigger. Stay tuned.
Had a fungus gnat infestation last year on my grow. "big infestation" Plants were in flowering. I did use neem oil while my plants were growing but couldn't completely exterminate them. They came back, had to use panty ho"s on each plant to trap the gnats then drown them. Used LOTS OF CINNAMON...