Mums are pretty straight forward to grow, the hard part is the "management". There are varieties that flower starting in early august up to October. My biggest struggle is the timing of the mums to flower when people want to buy. I start selling them on labor day weekend and then go through Halloween. It seems that people like to buy them when there are some flowers blooming but a lot more that are about to pop. For growing, I use a drip irrigation system. They like well drained soil (which mine is basically sand), but they don't like to get too dry. I also fertilize through the drip, they like to be fed. About every other time I spray the pumpkins for fungus and bugs I will fun the sprayer by the mums. I am not sure if they need it or not. The deer will go into the mums but they don't eat any. They step on a few. The weed control is a little bit of work. The weeds can mishape the mum if they get too big. I need to do something different than manual control next year. In Michigan they should be planted Mid June to Mid July depending on the size you want. I pot them when they are ready to go to the side of the road.
I really enjoy growing them.
Barry