Bonny,
Wintersowing can begin on the Winter soltice, a couple of weeks before or after it. There are no hard and fast rules. It can be adjusted according to your gardening zone or the micro-climate where you dwell.
Trading is prolific in the Fall, because a lot of gardeners have harvested fresh seed. Yes, it is a fun, economical, and easy way to get a large variety of plants. A lot cheaper than buying from a garden center, plus you will grow varieties & cultivars that the nurseries won't even carry! They cater to the mass market and usually carry items that will sell quickly and at the highest profit.
You won't need to sow every seed in the packet, unless you have a lot of acreage. We all tend to sow a bit "heavy handed". The key is to sow ONLY what you need....GOOD LUCK! If you sow too much, you can always trade your plants, give them to relatives, neighbors or friends. You'll always be able to make someone else's day a bit brighter with a lovely gift that will continue to grow.
Yes, you can save seeds from year to year....if stored properly. There are lots of different containers for saving seeds & everyone has their special way of doing so. I store mine in a large rectangular Tupperware type container, which can be burped to release the excess air. I divide my box with 4x6 cards into categories, such as annuals, herbs, perennials, veggies, vines and shrubs/trees. Also, the little packets of dessicant that come in new handbags & shoes are great to put in your container. They help to absorb excess moisture/humidity.
