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Tuber Vervain/Stiff Vervain
Berbena rigida (Verbenaceae)

A hardy, upright perennial native to Brazil and Paraguay which has naturalized throughout the southeastern United States. The intense, deep purple to magenta flowers are numerous producing a seemingly endless display of color. Does not seem to be temperamental about soil conditions but requires full sun. An outstanding trouble-free performer in hot-humid climates.

Average planting success with this species: 80%
Height: 12-24 inches
Germination: 21-45 days
Optimum soil temperature for germination: 68-86F
Sowing depth: 1/16"
Blooming period: April-October
Average seeds per pound: 760,000
Seeding rate: 3 lbs. per acre
Suggested use: Wooden barrels, borders, rock grdens, roadsides.
Miscellaneous: A prolific reseeder. Often forms large dense colonies that can outgrow its welcome in some areas; so plant accordingly. Can tolerate infrequent mowing.