As you know our weather is all wacky with no set seasons. I didn't even have mine finished before frost last year. I had to cover them a few times so I wouldn't have to bring inside. Last year I had some start flowering in mid August and a few in September. Generally it's day length unless your in thicker wooded areas. The ammonia trick is something I learned when I lived up north but have yet to have to do it here as my property is fenced in. I would assume they will react the same way to it though. Just make sure it's far enough away to not get run into yur grow with flowing rain water.