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Landmarks Spotlight: Native Seed Farm

PictureThe Native Seed Farm in bloom

Throughout the year, Irvine Ranch Conservancy works diligently to produce native seed that supports habitat restoration efforts across the Irvine Ranch Natural Landmarks. Since 2009, Irvine Ranch Conservancy’s Native Seed Farm has played a key role in these efforts by providing a reliable source of local native seed, while also creating unique opportunities for the community to connect with the land.
The seed production cycle starts with hand collection of a small batch of native seeds from the wildlands. Those seeds are the source material for the large plots of native plant species that are maintained on the farm. Seed production is a year-round effort. Since native plants are adapted to our Southern California climate, they grow in the cool, moist winters and bloom in the warm spring and summer sunshine. To align with this natural timing, annual wildflower seeds are sown on the farm in November and germinate with the winter rains. Perennial species are grown in the nursery over the summer, and seedlings are planted into farm plots in December and January. 

When the spring season arrives, there is an abundance of blooming wildflowers ready to be pollinated. These flowers eventually develop into fruits loaded with seed. Each native species flowers and produces seed within a certain time frame. The exact timing can vary with weather conditions, resulting in a harvest season that can last from early spring to late winter, with an average of 10 species being harvested at any given time. Each year, staff and volunteers harvest roughly 1,000 pounds of seed from these plots, which becomes available for current and future restoration projects.
But the seed harvest is only one part of the production cycle. There is still plenty of work to do once the seed has been collected from the plant. According to Irvine Ranch Conservancy Programs Director Matthew Garrambone, once seeds are harvested, they are dried onsite at the farm for 2-3 weeks. “After the initial drying period, seeds are stored at ambient conditions for an additional three months to allow for after-ripening, which is important for breaking seed dormancy,” explains Garrambone. Once the seeds have been after-ripened, each seed “lot” needs to be processed (cleaned), where the target seed is removed from the non-target material. This can take many steps and often involves specialized equipment. Once the seed lot has been cleaned, it is weighed and lab-tested for quality. This information gets added to the Conservancy’s digital inventory, while the seed itself is moved to a refrigerated shipping container to be stored in cool, dry conditions that help maintain seed quality over time.  
Every October, seed is removed from the inventory and blended together to create a custom seed mix for each of the Conservancy’s restoration projects. These seed mixes are spread throughout the project area in November, where they wait in the soil for the winter rains that promote their germination and establishment. The resulting seedlings will be defended from weeds by restoration staff and volunteers. With a little luck, and a lot of hard work, these seedlings will eventually become part of a functioning ecosystem, providing food and shelter for local wildlife. One example of this is the Bee Flat restoration project, which has helped revitalize large sections of Limestone Canyon.
Volunteer at the Native Seed Farm throughout any season to experience first-hand the process of harvesting seeds! Sign up to volunteer with It’s Harvest Time! Collect Wildflower Seeds at the Native Seed Farm on Wednesdays and Saturdays from 8:30 a.m. to 12 p.m. No experience is required, and tools and training are provided on-site by highly trained Conservancy staff and volunteers. To learn more about the Native Seed Farm and other stewardship activities and opportunities, visit