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Delta Blues™ Chastetree

Vitex agnus-castus 'PIIVAC-I'

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Delta Blues Chastetree

Discover More Information On Delta Blues™ Chastetree

Delta Blues™ Chastetree was the first intermediate variety of the species to be introduced, roughly two-thirds the size of the species, not nearly as coarse in texture, has richer blue-purple flowers that bloom from June to October, and dark and fragrant foliage. Delta Blues™ is deer resistant, salt tolerant, and adapts to acid or alkaline soils as long as the site is well drained. Introduced by Plant Introductions Inc.

Plant Attributes

Delta Blues™ Chastetree, botanically known as Vitex agnus-castus 'PIIVAC-I', is a distinctive cultivar known for its spectacular show of blossoms, unique form, and hardiness. It's a member of the Lamiaceae family, often called the mint or deadnettle family.

The Delta Blues™ Chastetree is a multi-stemmed deciduous shrub or small tree, generally reaching heights between 8 to 10 feet tall and about as wide, though it can grow even taller in ideal conditions. Its size makes it perfect for use as a specimen plant in a garden or landscape design, or in a mixed shrub border for eye-catching contrast. It has a moderate growth rate, is easy to maintain, and shows resistance to pests and diseases, contributing to its reputation as a low-maintenance plant.

The foliage of the Delta Blues™ Chastetree is a significant attribute, with palmately compound leaves that emerge a glossy, vibrant green. These leaves can be up to 12 inches long and provide a pleasant, aromatic scent when crushed.

The real showstopper, however, is the profusion of summer blooms. From late spring to early fall, the plant produces conical clusters of vibrant, rich blue-violet flowers that are very attractive to pollinators like butterflies and bees. The contrast between the striking flowers and the bright green leaves creates an appealing aesthetic.

Following the blooming period, it forms attractive, greyish-brown seed pods that add interest to the winter landscape. It's worth noting that the Delta Blues™ Chastetree is a heat and drought-tolerant plant, making it a suitable choice for warmer climates.

The plant prefers full sun to partial shade and well-drained soil. It can tolerate a range of soil types, including loamy, sandy, and clay, but does not do well in overly wet conditions. It's often recommended to prune in early spring to promote a more compact, bushy growth habit, though it's not necessary for the health of the plant.

Landscape Use

The Delta Blues™ Chastetree has several applications in landscaping due to its beautiful foliage, showy flowers, and impressive hardiness. Here are a few ways you might use this plant in landscape design:

  1. Specimen Plant: Due to its height, vibrant blooms, and attractive foliage, the Delta Blues™ Chastetree makes for an excellent specimen or feature plant. It serves as a focal point in gardens and yards, drawing attention with its seasonal color and unique form.
  2. Border Plantings: Planted in a row or group, these Chastetrees can create a vibrant, eye-catching border or privacy screen. Their dense growth habit also makes them useful for windbreaks.
  3. Butterfly and Bee Gardens: Given its prolific bloom that attracts a wide variety of pollinators, the Delta Blues™ Chastetree is a perfect addition to a butterfly or bee garden. It not only provides nectar but also adds aesthetic appeal with its bold, blue-violet flowers.
  4. Mixed Shrub Border: The Chastetree's contrasting flower and leaf color make it an excellent addition to a mixed shrub border. Its large, conical flower clusters stand out beautifully against other greenery.
  5. Xeriscaping: Because of its high tolerance to heat and drought, it is an ideal choice for xeriscaping, a landscaping style designed to reduce the need for irrigation.
  6. Coastal Landscapes: This plant's tolerance to salt and drought makes it a suitable candidate for coastal landscapes, where conditions can often be harsh and challenging for less hardy plants.
  7. Patio and Container Plantings: Smaller, younger Chastetrees can be grown in large containers. This makes them a good option for patio decoration or in urban environments where planting space may be limited.
  8. Park and Street Tree: Given its moderate size, the Chastetree is also appropriate as a park or street tree in urban landscapes.

In all these scenarios, the Delta Blues™ Chastetree offers the dual benefits of being visually striking and relatively low-maintenance, making it a versatile choice for a wide range of landscape designs.

Planting & Care

Planting and caring for a Delta Blues™ Chastetree involves understanding its preferences for light, water, soil, and general maintenance. Here's a basic guide:


  1. Location: Choose a location that gets full sun to partial shade. Chastetrees thrive in sunlight and produce more blooms when they get at least six hours of direct sun each day. They can tolerate partial shade, but you might see fewer flowers.
  2. Soil: The Delta Blues™ Chastetree prefers well-drained soil and can tolerate a wide range of soil types, from sandy and rocky soils to heavier clay soils. However, it does not do well in overly wet or waterlogged soil.
  3. Spacing: If you're planting more than one Chastetree, make sure to space them about 10 to 15 feet apart to accommodate their mature size and ensure good air circulation, which helps prevent disease.


  1. Watering: Once established, Chastetrees are drought-tolerant, but they will need regular watering during the first year or so to establish their root systems. Water deeply but infrequently to encourage deep root growth. The soil should dry out slightly between watering sessions.
  2. Pruning: Pruning is not strictly necessary but can help maintain a more compact and bushy growth habit. The best time to prune is in early spring before new growth begins. You can also remove the old seed pods in late winter or early spring to improve the plant's appearance and promote more vigorous flowering.
  3. Fertilizing: A slow-release, balanced fertilizer applied in early spring can help promote healthy growth and prolific blooming. Always follow the manufacturer's instructions when applying fertilizer.
  4. Pests and Diseases: The Chastetree is generally pest and disease resistant. However, watch out for common issues like aphids, spider mites, and scale. If these pests become a problem, they can often be managed with horticultural oils or insecticidal soaps.
  5. Mulching: Apply a layer of mulch around the base of the tree to help conserve moisture, control weeds, and maintain a consistent soil temperature. Be sure to leave some space around the trunk to prevent rot and pest problems.

Remember, the Delta Blues™ Chastetree is fairly low maintenance, but like any plant, it will benefit from regular care and attention. By providing the right conditions and a bit of basic care, you can enjoy this plant's stunning display of flowers for many years.

Additional Information

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Delta Blues™ Chastetree


Plant Features

  • Height: 8-10'
  • Width: 8-10'
  • Hardiness Zone: 6-9
  • Heat Zone: 9
  • Exposure: Full Sun
  • Habit: Rounded to Upright-Spreading
  • Flower Color: Dark Purple
  • Foliage: Dark Green

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