November 7, 2015

1 - You can store seeds overwinter if you keep them cool and dry.

Q.

I have been saving seeds from my garden and wildflowers in my yard all summer. As I would collect them I put them in paper bags to dry. Do I need to plant the wildflowers now? Can I save them and plant them next spring? If I keep them until spring will they survive in the paper bags? Also, what is the best way to save the vegetable seeds until next spring?

A.

Some wildflowers can be planted now. Wildflower seeds that mature in the summer naturally fall to the ground in the late summer and autumn. Some of these wildflower seeds germinate in the autumn soon after dropping from the parent plant, especially if the autumn is moist. These plants are biennials that require two growing seasons before flowering. The winter is an interval between the autumn growing season and the spring / summer flowering season. Cold temperature during the winter cause metabolic changes in the overwintering plants to induce flowering in the spring. This is not true for all wildflowers, but even those that are not biennial plants produce seeds that fall to the ground in the autumn and then germinate in the spring. If you plant them now, you will be following the natural process.

However, there are hazards that the seeds must survive during the winter. If the seed do not germinate in the autumn they are subject to predation by birds and rodents during the winter. They may also rot if they stay too moist. This is the natural process, many do not survive, but some do survive until the next spring. If you want to try to save some of the seeds indoors, you should store then under dry, cool conditions. The paper bag is usually adequate for storage through the winter. The cool conditions can be met by keeping them in an unheated room, in a garage or storage shed. While they remain dry, brief freezing in a storage shed should not damage native seeds.

These same storage conditions should be sufficient for your vegetable seeds. Dry, cool storage will maximize their ability to germinate well next spring.

If there is a possibility that rodents (mice, squirrels, and other such scavengers) could get into your seed in your storage location, you may want to store the seeds in closed jars after the seeds have completely dried. Some people store the seeds in jars with desiccant materials insure dry conditions. You can purchase such desiccants or make your own by drying rice on a cookie sheet in the oven at about 200 degrees for a few hours. After the rice has cooled, place it in the bottom of the jar, then cover the rice with a layer of paper towels to separate it from the seeds. Or just put the seeds into coin envelopes which are then placed into the jars. If the seeds are well dried in the air they may not need the desiccant. (Do not heat the seeds in the oven or microwave oven to dry them).

In the spring your stored seeds should be ready for planting.


Marisa Y. Thompson, PhD, is the Extension Horticulture Specialist, in the Department of Extension Plant Sciences at the New Mexico State University Los Lunas Agricultural Science Center, email: desertblooms@nmsu.edu, office: 505-865-7340, ext. 113.

Links:

For more gardening information, visit the NMSU Extension Horticulture page at Desert Blooms.

Send gardening questions to Southwest Yard and Garden - Attn: Dr. Marisa Thompson at desertblooms@nmsu.edu, or at the Desert Blooms Facebook page.

Please copy your County Extension Agent and indicate your county of residence when you submit your question!