Spring Blue-Eyed Mary, Collinsia verna

If any one plant got me interested in native annuals, Spring Blue-Eyed Mary, Collinsia verna, was it. I saw photographs on the internet of this plant blanketing the understory of a woodland scene in spring and it made me think of siberian squill.  But this plant was native to the US!!!  Its native range is in the north-central US (New York to Virginia and west to Kansas).

This plant has an unusual life cycle that can make it a little tricky to grow in a residential landscape.  It is a winter annual, meaning that the seeds germinate in the fall and that blooming occurs in the winter or early spring.  The seeds need to go through a period of warm stratification for a couple of months and then they germinate as the temperature begins to drop.  The seedlings sprout as the leaves are falling, between September and October, taking advantage of the sunlight that is now available. It forms a small, few-leaved rosette that overwinters. In the spring, the seedlings begin to grow before the trees leaf out, much like woodland spring ephemerals, reaching a height of 8-12 inches. Bloom time is from early April through May. The widely flaring bell shaped flowers have 2 white petals at the top and two bright blue at the bottom. The ½-inch wide flowers are borne in whorls of 4-6. The seed ripens and is released in June and remains dormant in the soil until the fall. Collinsia verna is found growing in rich moist woods and alluvial soil from southern Ontario to Tennessee and west to Kansas. Populations are declining and it becoming rare at the edges of it range.
What makes this plant tricky to grow is that it is coming up when gardeners are busy raking leaves and ripping out spent annuals and perennial stems.  One must be careful not to trample or weed out these new seedlings.  Also these plants prefer a shaded, moist site.  I had some in full sun and they were cooked after a couple of days of warm spring weather. 

Seed for C. verna is of limited availability. I was fortunate to get some in 2008, but it has since been discontinued by that supplier. Seed is best sown fresh in place in early summer.  I planted seeds in a variety of places and saw germination in October only under a Crabapple tree in an area that had fairly consistent moisture and abundant sun during the growth period in the fall. I have also found some plants coming up and maturing in the spring after spending the winter in the ground. Fortunately C. verna is known to self pollinate, so that even if only a few plants are successful, I may get viable seed for the next season.  If anyone knows of a supplier of these seeds, I would love to get a hold of some more.

Other species of US native annual Collinsia, hailing from the western states, are C. grandiflora (Blue Lips) and C. heterophylla (Chinese Houses).  Seeds for these plants are more easily obtained.