Chastetree (Vitex agnus-castus) may be grown as a large shrub or small tree.
Barbara H. Smith, © 2017 HGIC, Clemson Extension
Chastetree (Vitex agnus-castus) is a deciduous (loses its leaves in the fall), multi-trunked shrub or small tree native to southern Europe and western Asia. It is an excellent selection for southern landscapes in USDA zones 7 to 9 but will have cold damage or be killed to the ground in USDA zones 6 and colder. The leaves, flowers, and seeds are aromatic with a spice-like scent similar to crushed sage.
Mature Height/Spread
Depending on the variety, the mature size of a chastetree can range from 3 to 20 feet tall and wide. The larger varieties are fast growers and may be grown as a large, vase-shaped shrub or trained into a small tree.
Ornamental Features
The oppositely arranged, grey-green leaves are palmately compound (hand-shaped) with 5 to 7 lance-shaped leaflets. They are dark grey or blue-green on the upper surface and greyish-green underneath with fine pubescent hairs. There is no significant fall leaf color.
Chastetree (Vitex agnus-castus) attracts many pollinating insects, such as an Eastern carpenter bee.
Barbara H. Smith, ©2017 HGIC, Clemson Extension
The violet, blue, white, or pink 3- to-6 inch flower panicle (loosely branched flower clusters) are produced on new growth. They begin to bloom in June and continue until September. Removing old blooms will encourage new growth with a repeat bloom in about six weeks. The smooth, greyish-tan bark of a young tree will become a fissured dark grey as the tree matures.
It prefers full sun and loose, well-drained soil with adequate but not wet soil moisture. After becoming established, it does well in a hot, dry setting (e.g. xeric or water-wise garden) and tolerates drought conditions.
Landscape Use
Chastetree is resistant to damage by deer and is moderately salt tolerant. The fragrant flowers attract butterflies, bees, and other pollinating insects.
Due to the chastetree’s interesting foliage and late summer flowers, it can be used in shrub borders, cottage or butterfly gardens, or as a small tree.
Problems
Chastetree is resistant to most insect pests and diseases. If planted in soil that is not well-drained or remains wet, it can succumb to root rot and dieback. Leaf spots can be a problem, especially if overhead irrigation is used. Several cultivars are available that have resistance to leaf spot diseases.
Due to the possibility of reseeding, it can become invasive in some areas.
Cultivars
- ´Abbeville Blue´: This cultivar was selected in the early 1990s and will grow 6 feet tall and wide. It has 12 to 18 inch long, deep blue panicle flowers.
- ´Alba´: This large grower matures at the height of 10 to 15 feet and a width of 15 to 20 feet. The flowers are white.
- Blue Puffball™ (´PIIVAC-II´ PP26775): This compact cultivar grows 3 feet tall by 4 feet wide and is resistant to leaf spot diseases. The flower panicles are deep blue. First Editions® introduced it in 2016.
- Blue Diddley® (´SMVACBS´ PPAF, CBRAF): This 2015 Proven Winners introduction is a compact grower. It has lavender-blue flowers on a 3 to 6 feet tall and wide shrub.
- Delta Blues™ (´PIIVAC-1’, PPAF): The blooms are dark purplish-blue, compact panicles. The foliage is more refined, and the plant will grow 8 to 10 feet tall and wide.
- ´Rosa Ann´: This variety will reach a height of 8 to 15 feet tall and 10 to 15 feet wide. The fragrant flower spikes are pink.
- ´Shoal Creek´: This is one of the more commonly available varieties and matures at 10 to 15 feet tall and 15 to 20 feet wide. The large, blue-violet flowers are 12 to 18 inches long. Foliage is resistant to leaf spot. In 1983, Goodness Grows Nursery in Lexington, Georgia first introduced this cultivar.
This variety of chastetree (Vitex agnus-castus ‘Alba´) has beautiful white flower panicles.
Barbara H. Smith, ©2017 HGIC, Clemson Extension
The Shoal Creek chastetree (Vitex agnus-castus ´Shoal Creek´) was introduced in 1983 by Goodness Grows Nursery.
Barbara H. Smith, ©2017 HGIC, Clemson Extension.
Originally published 09/17
