The long, upright spikes of pink, lilac, and white flowers of Vitex (chaste tree, Vitex agnus-castus) bloom from late spring to early fall. While any plant that blooms all summer is a great addition to any garden, having fragrant flowers and foliage makes it even more desirable. The care of chaste trees in the garden is straightforward, but there are a few things to keep in mind if you want to get the most out of this remarkable plant.
Summer brings purple flower clusters to Vitex (Vitex agnus-castus), a deciduous shrub. Five leaflets in a palm-shaped arrangement are found on the vitex leaves, which are similar to those of the marijuana plant (Cannabis sativa). A sage-like scent fills the air when the leaves are brushed against the skin. Butterfly bush-like purple flower clusters (called panicles) adorn this plant (Buddleja spp.) The four seeds of the black fruit, which resemble peppercorns, are sometimes used to season food.
As with most shrubs, vitex needs a good amount of time to establish roots before it goes into dormancy in spring. Most gardeners prefer to keep this potentially invasive plant at a height of 10 feet or less because of its rapid growth. It can reach a height of 7 feet in a single season.
Charismatic Tree Data
A Chinese native, the chaste tree has a long history in the United States. First grown in 1670, it has since spread throughout the south of the country and has become a naturalized species. A lot of southerners use it as an alternative to lilacs, which can’t withstand the heat of a southern summer.
Small trees, chaste trees can reach a height of 15 to 20 feet (5-6 m) and a width of 10 to 15 feet (0.5 m) (3-5 m.). Butterfly and bee pollinators love this plant, and it’s a great source of honey, as well. Animals avoid the seeds, which is fortunate because if you want to keep the plant flowering, you’ll have to remove the flower spikes before they set seed.
It’s Vitex!
There are a few obstacles for a home gardener to overcome when cultivating Vitex. Success is almost assured if you avoid soil that is too wet or dense. The vitex’s biggest drawback is its tendency to grow out of control, necessitating regular pruning to keep it in check. It is possible for a plant to become invasive if it escapes from a garden and becomes established in the wild. For those in the southern states, where this is a prevalent issue, contact your local garden center or cooperative extension service for advice on how to successfully grow vitex.
Butterflies and other pollinators adore the flowers, which are commonly used in shrub borders, foundation plantings, and butterfly gardens. This plant is often used as an alternative to lilacs, which don’t grow well in very warm climates, in southern gardens. The sparing use of irrigation water makes it an excellent choice for xeriscape gardens as well.
The Vitex genus contains only one temperate species, with the rest being tropical trees and shrubs. As with the butterfly bush, this plant can be grown as a perennial in colder climates (zones 5 and 6) where it dies back in the winter, much like the butterfly bush.
Light
Vitex thrives in a wide range of growing conditions, from full sun to partial shade, with the best flowering occurring in the former.
Soil
Choose a location where water drains away rather than accumulates. This shrub can tolerate soils ranging from acidic to slightly alkaline, but it does not do well in soils that are too rich because the roots will retain too much moisture. This plant, which is native to the Mediterranean, does best in soil that is not too wet. It doesn’t matter if the soil is sandy or rocky.
Water
Once a vitex is established, you won’t need to water it again for several years. Organic mulches, on the other hand, should be avoided because they retain too much water.
Humidity and Temperature
Although it is only hardy to -9 degrees Fahrenheit, Vitex agnus-castus can be grown anywhere from Zones 6 to 9. As a result, it is often grown as a perennial plant rather than a shrub in zones 6 and 7, where the plant may die down and re-grow each spring. As a result, it can thrive in both humid and dry climates across the country.
Fertilizer
Feeding a vitex is minimal, if not non-existent. A single application of a general-purpose balanced fertilizer every year or two is all that’s required to get the job done.
Types of Vitex
It is common to find the following cultivars of vitex:
- Abbeville Blue: As with ‘Abbeville Blue,’ ‘Abbeville Blue’ reaches a height and spread of 6 feet. Its 12- to 18-inch stems are covered in deep blue flowers.
- Alba: There are white flowers in ‘Alba’ It’s a big one, reaching a height of 15 feet and spreading out to a width of 20 feet.
- Shoal Creek: There are no fungal spots on the leaves or flowers of Shoal Creek, which stands 15 feet tall and has a purple-blue flower.
- Blue Puffball: is a great small shrub with delicate blue flowers that grows to only 3 feet tall.
- Rosa Ann: It is a 15-foot-tall plant with scented pink flowers, and it is known for its strong scent.
You can pot Blue Diddley (which grows to 6 feet) and Blue Puffball, which are both smaller varieties (grows to 3 feet).
Pruning
Vitex, if left unpruned, can develop into a 20-foot-tall, equally-wide-spreading vase-shaped shrub. As a small tree, it can be trained as a single trunk.
Deadheading spent flowers is a good way to keep your shrubs producing, but it can be a bit of a pain if you have a large one. During the winter months, it is best to prune the shrub to keep it in shape and control its size. Vitex is able to handle a lot of pruning. In order to encourage a central leader, you can prune completed shoots from vitex trees to grow them into small trees with just one trunk.
As winter approaches, this plant is frequently trimmed to the ground in colder regions. Your vitex will grow back to a 3- to 5-foot flowering shrub each year, even if you prune it severely. This is because it blooms on new wood.
Keeping Vitex in the wild
Rooting branch cuttings is the simplest way to propagate a vitex plant. Vitex roots readily, as one might expect from a plant of this ease of cultivation.
- Clip the end of a limb that is about 12 to 18 inches long.
- Remove the flowering end.
- Remove the lower half of the cutting’s leaves.
- The cutting should be placed in a vase of water and placed somewhere that gets morning sun but afternoon shade.
- Planting the cuttings in moist potting soil will also work to root them.
- Existing leaf material will fall off of the cuttings after about two months, but the other growth nodes will begin to bud and send out new growth.
- It is possible to plant a cutting into a pot or a garden after it has developed hairlike roots on the bottom.
Repotting Vitex Plants
Smaller varieties of vitex can be grown in pots. Smaller cultivars only reach heights of 3 to 6 feet. It is possible to keep the tree in the same pot for a few years before you need to repot. Take a few minutes to do this:
- A tree’s root ball should be measured.
- Ideally, the root ball should have a container with a diameter of at least 8 inches greater than the container’s own diameter.
- Drainage can be achieved by using a planter with holes in the bottom or by using a drainage planter. Line the planter’s holes with landscape fabric to keep dirt from escaping.
- Potting soil should be high-quality and well-draining.
- Drainage can be improved by adding 10% perlite to the mix.
Typical Insects and Pathogens
Root rots, nematodes, and leaf spots are the most common problems you’ll encounter on Vitex agnus-castus, but even these are rare. Typically, issues arise when the soil isn’t completely dried out before planting. Aphids, whiteflies, and scales can also be a problem, but horticultural soaps and oils are usually enough to get rid of them.
