Slender dayflower is a close look-alike to the annual, weedy Asiatic dayflower. This species is perennial though and more upright with large blue flowers with very rounded petals usually in pairs with no third petal. Plant is wispy and spreads slowly forming large patches in moist to dry, sandy or stony soil. Grows 1-2 foot tall. Flowering occurs July-September. Zone 5-9. VA ecotype. // About 30 seeds per packet. Germination requirements: 60 days cold-moist stratification.