Lindgren, D.T.; Schaaf, D. 2007. Penstemon: A summary of interspecific crosses. HortScience. 42(3): 494-498.
Lindgren, D.T.; Schaaf, D. 2007. Penstemon: A summary of interspecific crosses. HortScience. 42(3): 494-498.
Western Forbs
Lindgren, D.T.; Schaaf, D. 2007. Penstemon: A summary of interspecific crosses. HortScience. 42(3): 494-498.