I made the mistake of putting a fertilizer I had from my vegetable garden and then noticed it 90% nitrogen. Within days my leaves started to turn yellow. I flushed it with water but not a whole lot. I was afraid to over water them. Now they are still alive but have slowed to a crawl in growth. I used auto flowering white widow and the plant Im having trouble is loaded with buds. They are about 5 weeks old. What to do?
You did the right thing flushing right away. You need to poor about at least twice the volume of water as the volume of soil through the container slowly, allowing it to drain well before flushing again in about an hour.
You could think about getting something like Luster Leaf 1818, “4 in 1” Rapitest Mini Tester soil probe or a EC/TDS/PPM meter to be able to test your run off and make sure things aren’t too hot or overly fertilized.
Most soil growers recommend 3 times volume for flushing. Just sayin’