The University of California Agriculture and Natural Resources released a seed distance chart on Apr. 13, providing guidance on pollination, isolation distances, and seed-saving practices for various vegetables.
This information is important for gardeners and farmers who want to maintain the purity of their vegetable varieties and ensure successful seed saving. The chart details recommended isolation distances between different varieties to prevent unwanted cross-pollination, which can affect the quality and characteristics of saved seeds.
The guide includes specific recommendations for crops such as beans, soybeans, beets, chard, broccoli, kale, cauliflower, carrots, celery, corn, cucumbers, eggplants, leeks, onions, lettuce, melons, mustard greens, peas, peppers, radishes, spinach, squash or pumpkins and tomatoes. For each crop it lists whether they are self- or cross-pollinated; required isolation distances; average seed longevity; ease of saving seeds; whether direct seeding or transplanting is recommended; and additional notes about hybridization risks or special considerations. For example: “Crossing among brassica species is complex. Consult a good reference book.” The chart also clarifies that all self-pollinated vegetables are easy to save while some cross-pollinated ones require extra knowledge to maintain varietal integrity.
University of California Agriculture and Natural Resources secures funding through public contributions to support its programs according to the official website (source). The organization promotes sustainable practices designed to strengthen resilient ecosystems as well as economic vitality (source). It operates nine research and extension centers serving as laboratories that represent California’s diverse ecosystems (source), has gained recognition for linking research with community needs (source), manages Cooperative Extension services within the University of California system (source), conducts over 33, educational events annually while engaging more than 18, volunteers in its initiatives (source).
With this resource release aimed at supporting best gardening practices across communities in California and beyond—alongside ongoing education efforts—the University continues its role in connecting science-based agricultural knowledge with practical local applications.