San Francisco gardeners know: April is a prime month for planting peas, beets and lettuces.
A group of activists and gardeners wants you to plant seeds that come from local vegetables as well.
Visit the Potrero branch of the San Francisco Public Library and you'll spot a display with rows of little yellow envelopes: the San Francisco Seed Library. Created in 2011, the exchange offers free seeds for the taking, many of them ideal for planting right now. Most come from donations and volunteers' gardens, so it's fitting that the library is housed in the sunniest, most garden-friendly swath of town.
The trade-off? Come harvesttime, the organizers hope you return good seeds from the plants you grow to keep the library's collection expanding. Their mission is for participants to collectively discover the vegetable, legume and grain varieties that will flourish in our quirky climate.
Harvesting seeds to return to the fledgeling seed library is not as straightforward as it looks, however. If you want to learn more, the Berkeley-based Bay Area Seed Interchange Library is offering a seed-saving class on Saturday, April 13. And urban-agriculture activist Antonio Roman-Alcalá will be teaching several classes at the Potrero library in June. (Check the branch's online event listings in a month or so for times.)