Spiderwort Family (Commelinaceae)

Commelinaceae diversity reaches its peak in tropical and subtropical areas of the world. Perhaps nine genera have been documented in North America.

Southeastern states show the largest Commelinaceae diversity. A state such as Texas, for example, might have a couple dozen species divided among five general.

Regardless of the location, most people recognize spiderworts based on two genera, dayflowers (Commelina) and spiderworts (Tradescantia).

Species from each of the genera grow hardily in the wild across the United States. Spiderworts also raise a fair it of enthusiasm among gardeners.

When thinking spiderworts and dayflowers, think clumps of grass that sprout flowers. Discrete clusters of spiderworts and dayflowers can easily be managed in a garden setting by consisting trimming leaves and dividing the plant by the root system every few years.

Spiderworts tropical and subtropical background suggests that the plants enjoy a sunny, moist environment. While most native species might be partially shade tolerant and adaptable to USDA zones from 4-9, sun and moisture enhance the plants flowering capacity.

The Tradescantia genus contains about thirty native species. With the exception of the Pacific Northwest, their range extends across the United States.

The top picture shows a Tradescantia species with the typical three petals and six yellow anthers.

Thirteen different dayflower (Commelina) species grow east of the Rocky Mountains.

A few Commelina species are introduced and naturalized. Most of the species are characterized by the blue petals that bloom for a day and then fade.

Dayflowers also tend to form large clumps, so over the course of a flowering season, the clump continues to produce blooms.

Sometimes species from both genera grow aggressively, and in instances where non-native species are introduced, some dayflower and spiderwort species receive the weed label.

© 2008-2011 Patricia A. Michaels