What do the weeds look like when they are too young to flower
A quick internet search will reveal what you will want to look for! What I can do is point you to an article that will help you with their care:
Will they grow when the husk covering was removed?
You can remove any loose, old husks before planting.
When storing them for winter, it's advised to leave the husks, but that likely helps to keep the corms dry during storage.
I've left it till now because you are meant to leave the foliage till it turns brown.Mine are still green but covered with snow now..do I lift them now or wait a bit longer?
After this frost kills them off, completely, then you can dig them up. Here is an article that will help:
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/storing-gladiola-corms.htm
I planted my calla lilies and peacock glads last year and the plants were big and luscious but no flowers. What type of potting soil do I need?
Since you had that issue last year, I would go with a commercial mix that does not have fertilizer in it. All the big box brands have fertilizer in them, so you may have to go to a plant nursery to get a bag. Then you can control the amount of fertilizer, especially nitrogen, your plants are receiving. Here is how to take care of them:
https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/feeding-calla-lily-plants.htm
https://www.gardeningknowhow.com/ornamental/bulbs/calla-lily/make-calla-lily-bloom.htm
On the peacock orchid, if you grow them as annuals, you don't need fertilizer. If they overwinter or you bring them inside over winter, the next spring add some 5-10-10 slow release fertilizer as a side dressing.
https://www.gardeningknowhow.com/ornamental/bulbs/peacock-orchid/growing-peacock-orchids.htm
I started my glads indoors and they are about 18" tall. When I transplant them outside after all risk of frost in 4 weeks, how high can the soil line be? Can I bury them about 4 inches up the green blades?
You should plant them the same height they were indoors to avoid stem rot.
Glads have been removed from bed. Can they be treated w/fungus powder & be replaced next yr?u
Did they have powdery mildew or what type of fungus? Had the leaves died back? Glads are the type of plant that you need to let the leaves die back before digging them up. So, if they were dug up prematurely, I would just toss them.
If the leaves have died back and it was a foliar fungus, you can cut off the leaves for storage of the corms. Here is how:
https://www.gardeningknowhow.com/ornamental/bulbs/gladiola/storing-gladiola-corms.htm
My experience with bulbs has been if something cuts off the top of the stem, it doesn't grow back that season. However, if your gladiolus bulb was the large size that produces more than one stem, those stems should still come up.