Free Plants By Mail (freeplantsbymail.org) was started by local growers as a way to use the surplus plants from nurseries and also as a way to support The Nature Conservancy. Free Plants By Mail offers a new free plant each month. This month they are offering Agave "Century Plant". It takes 100 years for this agave plant to bloom! Although the plant itself is free, you do have to pay a small shipping and handling fee of $6.95.
This organization also has over 100 plants available for sale on their site. 100% of the proceeds from the sale will go to The Nature Conservancy.