Larry Sagers had a column a few weeks ago that discussed new plant varieties (see: deseretnews.com | The dirt on new plant varieties).

In it, he mentioned two books I should get:

In addition to Nau’s work with new varieties, he is the author of “The Ball Culture Guide,” which is the authoritative guide on propagating annuals from seed, and “The Ball Perennial Manual,” which is the companion volume for perennials. Both books are used by local growers.

I’ll have to check around and see where to buy these.