I bought a bag of shallots at the store. If I plant these, will they grow?
As long as they have not been irradiated, yes, they should grow. Here is more information on growing shallots: https://www.gardeningknowhow.com/edible/vegetables/shallot/tips-for-growing-shallots.htm
I'm a small balcony gardener and my shallots are about 3 weeks old. What do they look like underneath the soil? How big a pot and how many shallots can I expect from each plant?
Shallots adapt well to growing in containers as long as they are well-drained. You'll have to water and feed them a little more--the way you do any container plant. As a rule of thumb, for the smaller more shallow-rooted plants, like shallots, use a minimum container depth of 12", and for the larger varieties 18"-24" deep.
I can't find shallots anywhere to plant in the garden. Can I use shallots from the grocery store?
You can. They will be more expensive this way, but if you can't find them from a seed company, there is no reason you can't do this.
I planted garlic and shallots last fall and I checked one of each of them and they have beautiful tops but no bases! That shallots look like scallions and the garlic has no head at all. The shallots are starting to flower and some of the tops are browning and falling over, so it seems like they would be ready by now. Is it possible that they just aren't done yet or did I do something wrong?
It sounds as if they may have bolted. Here is more information: https://www.gardeningknowhow.com/edible/vegetables/vgen/what-is-bolting-what-it-means-when-a-plant-bolts.htm
My shallots are already going to seed. A thick stem with a large seed flower is shooting out of the plant. Should I let it flower or cut it off to have the best results? In years past, I have always cut it off when they appear. Also, should I be planting them in the fall instead of spring?
Your plants have bolted. These articles should help:
I know that the scapes on garlic need to be cut in order for the bulb to grow. Is that true of the shallot 'flowers'? I don't know whether to leave them or cut them.
Shallot flowers are round like an onion, but they don’t get that distinctive scape appearance. Grow shallots as you would onions. During the growing season, some of the leaves may be cut at the ground level and used as green onions. Plants that are not heavily cut will proceed to form many bulbs attached together forming a clump. Shallot bulbs often develop on top of the ground.
Here is an article that you may find helpful: https://www.gardeningknowhow.com/edible/vegetables/shallot/tips-for-growing-shallots.htm
If I buy a few shallots at the store and plant them, will they grow? Or do I need to start them as seeds?
This article will help: https://www.gardeningknowhow.com/edible/vegetables/shallot/tips-for-growing-shallots.htm