After it flowers and turns brown, should I just leave the bloom or cut it off?
You should deadhead the spent flowers to keep your plant producing more blossoms. Make sure you only trim the spent flowers and don't cut into the stem. New flowers form on the existing stem.
Should balloon flowers be cut back in the fall?
You can cut them back in fall after the stems die, or wait till spring. Both are fine. The plant can benefit from either having the old stems left on to protect the roots, or from the addition of a little mulch.
Planted Balloon Plant seeds in an organic seed starter after it was moistened. After I LIGHTLY COVERED THEM IN A PLASTIC BAG; SHOULD I MIST THEM AND IF SO HOW OFTEN?
You should keep the soil moist at all times until the seedlings pop up through the soil, then you can harden the seedlings off by removing the plastic bag for a portion of each day and watering less. If you leave the covering over them and keep them too moist they will get leggy a dampen off. This article may help:
how to grow
This article will help you.
Does pruning the seed pod after it flowers encourage more flowers to grow on the stem?
Yes, keeping the plant dead headed and from producing seeds will help encourage continued flowering.
I planted a balloon flower a month ago and it hasn't grown. It gets morning sun till around 2 pm. Why won't it grow?
Make sure the soil is moist to keep this plant happy.
Your plant looks healthy and is likely just settling it's roots.
I live in Michigan and want to prune my balloon flower for the winter. I will be leaving shortly for Florida and will be back late May. Is it too late to prune?
You can prune them at this time. Just be advised that these plants can tend to be hard to divide out, so as long as you aren't removing them from the soil they will be fine. This article will help: https://www.gardeningknowhow.com/ornamental/flowers/balloon-flower/growing-balloon-flowers.htm