Tall Blue Lettuce (Lactuca biennis) vs. Canada Lettuce (Lactuca canadensis)

Lactuca species have notoriously variable leaf shapes. These species are often confused by people unfamiliar with them, but they are usually easy to tell apart, especially when they are blooming or making seeds. There is significant overlap in habitat, and plants can often be found growing side-by-side, but L. biennis is slightly more shade-tolerant and more restricted to partly-shaded, moister habitats, and more neutral soils, whereas L. canadensis ventures into drier, sunnier conditions, ranges much farther south, and is more tolerant of acidic soils. Because of variability, it is important to check multiple characteristics.

View Full Guide