Marigolds are cheery, bright orange and yellow spots in the landscape. Taller varieties do well as a backdrop for other plants in a flower bed, and shorter varieties are perfect for planting along a sidewalk or border. Mix either size in a hanging container to add contrast and interest. Although purchasing marigold starts from a greenhouse or nursery is the easiest way to get started, gathering seeds from existing marigolds can be very rewarding.
Leave a few marigold blooms on the plants until they wilt, dry up and turn brown. When the bloom dries, you'll be able to see the swollen pod at the base of the bloom.
Hold the flower with one hand and pull it away from the seed pod. The seeds will be at the end of the pod that was attached to the bloom, and will easily come apart from the pod. The seeds will be long and skinny. One end will be grayish-black and the other end will be golden-colored. If the seed is green, it isn't ready to be harvested.
Open the pods and let the marigold seeds drop onto a paper plate. Leave them on the paper plate for several days, until they're completely dry. Don't worry about removing the chaff, which is the end that will come away from the seed.
Put the marigold seeds in a sealed container and put the container in the freezer until spring. Label the container, including the date and location where you gathered the seeds.