I went to market to buy Kale or (Romental Kale) and the man sold me curly. Will it turn into a flowering one? I'm going to eat them anyway if they don't. They are beautiful now, but I really wanted the ones that bloom with flowers of color.
Your curly kale will bloom, but there's no way for me to say what color they'll be.
I live in the Seattle area. I planted Russian Kale in early spring as part of an 'edible garden. ' It has grown well, and about 28 inches tall, with leaves that start about 12-14 inches up from a thick stalk. Should I just leave it through the winter or prune it in some way?
We would recommend that you not prune it now. Pruning now could cause it to send out new growth, which would make it more vulnerable to cold damage.
Our kale from last year appears to be going to seed, and it is early spring. What do we do, remove the flowers or cut them off?
Typically, once bolting occurs, there is little you can do for the plants. You can, however, cut the flowers to collect the seeds. For future reference, these articles may help: https://www.gardeningknowhow.com/edible/vegetables/vgen/what-is-bolting-what-it-means-when-a-plant-bolts.htm
https://www.gardeningknowhow.com/edible/vegetables/kale/growing-kale.htm
Can I keep winter cabbages if winter is over?
Yes, as long as you have conditions that it will grow in, you can continue to grow them.
When Kale has gone to seed, do you cut off the stalks or leave them?
Cut them. Unfortunately, once bolted the plant may not be any good. Here is more information: https://www.gardeningknowhow.com/edible/vegetables/vgen/what-is-bolting-what-it-means-when-a-plant-bolts.htm
When kale goes to seed, can I still eat the leaves?
If it is beginning to flower, then the plant is bolting and will not be any good for anything else except its greens. So, yes, you may still enjoy the leaves.
Here is more information on bolting: https://www.gardeningknowhow.com/edible/vegetables/vgen/what-is-bolting-what-it-means-when-a-plant-bolts.htm
I planted my kale around the end of September and it is just now starting to grow shoots. Can I somehow mulch it or something so that it will grow again next spring?
Yes, in milder regions kale can survive over winter. I am not sure how well it will do in your area but it is always worth a try, so go ahead and mulch the plants well. If you can possibly provide additional protection with row covers, that would likely be better.