Collecting seeds is the easiest way to get new and fresh plants for your garden. With just a few guidelines, one can easily supply themselves and friends with lots of goodies for the following year.
Collecting seeds that have been pollinated is best. This means nature has done the work for you - the wind, bees, and the insects have done the pollination. The opposite of this is hybridization where breeders decide parents and try to develop a plant with 'new and improved' characteristics. Open-pollination will create plants just like the original. However, every so often an unusual plant might occur.
It is important to let the seed mature on the plant. The embryo needs to continue developing. The seed will be either brown or black. Most often seeds mature about a month after the flower.
Start collecting seeds during the dry part of the day to mid afternoon. This is to prevent any possibility of molds. By your experience, you will learn the special habits of certain plants. Some collecting can be tricky. Some of the seeds stay nicely in their pods and some shoot around like rockets (like old fashion balsam). Seeds tend to mature at different rates on a plant so there will be several opportunities to collect.
One technique is to tie paper bags over potential seed heads. When the seeds are ready one can then cut the entire stem.
Seeds need to be sorted and separated. Spread the seeds on a paper plate and sift as if panning for gold. This will separate the extra shaft and will keep your seeds cleaner. This does not have to be perfect.
Seeds must be entirely dry for storage. Little packets of silica gel can be added to keep the containers dry once the seed has been deposited.
Storage of seeds can be in an envelope, a film canister, or even a jar. Be sure to label with enough information that you feel is needed for yourself and friends. Keep in a cool dry place.