Tom Clothier has a number of seed germination databases on a wide range of plant types: annuals, biennials, perennials, shrubs, and even a dedicated Penstemon germination database! He also has several articles, and an index for Norm Deno’s works.

Alplains is run by Alan Bradshaw in Colorado. In addition to providing a great seed catalogue containing many western natives, his site is also a great resource for germination requirements of many plants.