PlantFiles: Beach Vitex, Round-leaf Chaste Tree
Vitex trifolia subsp. litoralis

I have been working to remove beach vitex from coastal South Carolina since 2006 where it is growing on the beach front and has become a noxious invasive.It is a prolific seed producer and these seeds are carried to other sites including uninhabited barrier islands and protected natural areas.Along beach front communities it is a maintenance nightmare and will grow over beach walks, guardrails and other established plants. Beach vitex will completley cover a site, and the native beach plants such as sea oats,bitter panicum,silver leaf crotonetc wil be crowded out.The waxy cuticle on the leaf will be aborbed into the soil after the leaves have fallen and makes it extremely difficult to restore native plants after removal.Very strong herbicides are required to effectively treat and kill this plant and it often requires repeated applications.Seeds remain viable for up to 5 years.
Production of 5000 + seeds sq/yd can be expected when the plant is well established.Runners grow rapidly and root at each node.The entire plant has to be treated for effective removal since the many roots will allow runner segments to form separate individual plants.Cuttings will root if disposed of improperly and have plants have turned up on vacant lots and roadside from improper disposal.
If you do decide to plant beach vitex please exersize great care in the maintenace of it. Many communities in North and South Carolina have passed ordinances prohibiting this plant
or at a minimum requiring owners to keep it controlled.
If you live in an inland area and are a skilled and active gardener you MIGHT be able to handle Beach Vitex. If not do yourself and your community and neighbors a favor and pass it bye.Beach vitex is infinately worse to deal with than even kudzu.

Changing my comment from positive to neutral -- I don't think I'd plant it even here in Zone 6 near the beach or sandy wetlands.

Arnold Arboretum is growing this plant here in Zone 6. I don't know how long they've been growing it, but it looks like it's been there a while, and I'll be interested to confirm if it overwinters. It and Vitex agnus-castus are both invasive species in more southerly climes, but it would seem there's little potential (NOT in coastal areas) for that this far north. The latter is most often treated as a dieback shrub here.

This is not bad if you want a specific area covered with thick vegetation. It spreads with runners before you know it.

Other common names for Vitex rotundifolia include kolokolo kahakai, hinahina kolo, manawanawa, mawanawana, pohinahina and polinalina. It can be found growing natively throughout the Pacific and as far west as India.

Vitex rotundifolia is drought and salt spray tolerant and spreads by runners. Because it has become very invasive in some coastal settings, it is not recommended for coastal landscapes. Due to its invasive nature, I have to give it a negative rating.

An Asian plant introduced in South Carolina as a dune stabilizer. It has the potential to be an aggressive invasive species on the order of Kudzu. Has allelopathic properties, very salt tolerant, crowds out native beach grasses.