Chastetree, Monk’s Pepper Tree, Vitex agnus-castus

Summary:

Foliage: palmately compound with five dark gray-green leaflets; deciduous
Height: About 15 feet
Spread: About 15 feet
Shape: Upright broad multi-stem shrub or vase-shaped small tree

Main features: Chastetree is a large fast-growing shrub or small tree that produces showy pale violet flowers in June/July through September. This species is quite drought tolerant. It can be treated as an herbaceous perennial by cutting down most of the plant (to about 12 inches above ground) in the fall; the next growing season it will be at least 8 feet tall and produce a full set of flowers (flowers on new wood). A related species, Vitex negundo, also called chastetree, is quite similar to V. agnus-castus but is a zone hardier (zone 6) and has shorter flower panicles.

Plant Needs:

Zone: 7 to 8; can be used in zone 6 but will stems will be damaged/killed in hard winters (but will re-grow)
Light: Full sun
Moisture: Average to dry
Soil type: Well drained
pH range: Acid to alkaline

Functions:

This plant is suitable in mass or border planting.

Care:

No special care is needed. Chastetree can be treated as an herbaceous perennial by cutting down most of the plant (to about 12 inches above ground) in the fall; the next growing season it will be at least 8 feet tall and produce a full set of flowers (flowers on new wood).

Additional Information:

This is an attractive large shrub/small due to its summer flowers. The appearance of this species on the invasive and exotic plant list of invasive.org gives reason for caution; however, there are no empirical data to substantiate an invasive claim.