Spiderwort (Tradescantia (Andersoniana Group) 'Concord Grape')

Overview

Tradescantia (Andersoniana Group) ‘Concord Grape’, commonly known as Spiderwort, is a reliable herbaceous perennial cherished for its striking, three-petaled flowers set against attractive, bluish-green foliage. As a hybrid of the Andersoniana Group, this specific cultivar offers rich purplish-blue coloration reminiscent of Concord grapes, making it a standout performer in the late spring and summer garden. Gardeners value this plant not only for its bloom color but also for its adaptability, thriving remarkably well in moist and even boggy conditions where other perennials struggle.

This compact cultivar typically reaches about one foot tall, forming neat clumps perfect for edging or mass planting. While individual flowers open for only a single day, the plant compensates by producing numerous buds that open sequentially from May through August, ensuring a long season of color. The genus name, Tradescantia, honors the famous father-son gardeners of the 17th century, rooting this plant firmly in horticultural history.

For perennial borders or rain garden designs, the Spiderwort provides excellent texture and clear color contrast. Its ability to tolerate significant moisture fluctuations, coupled with its relative ease of care, makes Tradescantia (Andersoniana Group) ‘Concord Grape’ an indispensable choice for gardeners seeking reliable performance in damp areas of the landscape.

Fast Facts

• Plant Family: Commelinaceae
• Plant Type: Herbaceous perennial
• Hardiness Zones: USDA Zones 4-7
• Size at Maturity:
  • Height: 0.75-1 ft
  • Spread: 1-1.5 ft
• Bloom Time: May to August
• Bloom Description: Purplish blue
• Sun Exposure: Full sun to part shade
• Water Needs: Medium to wet
• Maintenance Level: Medium

How to Grow

Planting Tradescantia (Andersoniana Group) ‘Concord Grape’ is best done in spring or fall in average, well-drained soil. While it prefers moist, acidic, and humusy soils, this Spiderwort is highly tolerant of wet conditions, making it an excellent candidate near ponds or in rain gardens. Ensure it receives full sun for the best flower production, though it can tolerate partial shade, which might slightly reduce blooming intensity.

Water needs are medium to wet; aim to keep the soil consistently moist, especially during dry spells, as it readily handles wet, boggy soils. Fertilizing is rarely necessary if the soil composition is adequate. Maintenance requires attention to deadheading; remove each spent flower cluster promptly after all buds have opened to encourage continuous flowering.

As summer heat peaks, the foliage of many spiderworts can start to decline or sprawl unattractively. For Tradescantia (Andersoniana Group) ‘Concord Grape’, though foliage decline is often less severe, it is common practice to cut the entire plant back hard, nearly to the ground, in mid-summer. This hard prune stimulates fresh, attractive new leaf growth and often triggers an encouraging secondary bloom well into the late summer or fall. Clumps should be divided every few years if they begin to look overcrowded.

Landscape Uses

The versatility of Spiderwort lends itself well to several landscape applications, most notably in wet areas. These plants are highly recommended for rain gardens, where their tolerance for medium to wet water regimes is fully utilized. They perform beautifully along the moist margins of streams or ponds, blending naturally into the landscape.

Beyond wet spots, Tradescantia (Andersoniana Group) ‘Concord Grape’ excels in mixed perennial borders, providing vertical interest and vibrant color that contrasts nicely with finer-textured plants. They also integrate seamlessly into wild gardens or open woodland areas where filtered sunlight and consistent moisture are present. Their compact habit ensures they don’t overwhelm nearby plantings, making them perfect for adding a burst of purplish-blue near pathways or in naturalized meadows.

Standout Features

Flower Qualities

• Showy

Noteworthy Characteristics

Tradescantia, commonly called spiderworts, is a genus of about 65 species of herbaceous perennials from North, Central and South America. They are grown for their showy, three-petaled flowers and attractive foliage. The Andersoniana Group of hybrid spiderworts are some of the most common perennial spiderworts seen in cultivation. ‘Concord Grape’ is a compact, clump-forming cultivar which typically grows to 12” tall, displaying flowers accented by contrasting yellow stamens borne in terminal clusters. Numerous flower buds form in each cluster, but individual flowers are ephemeral, opening only for one day in succession from May into August.

Tolerances

• Wet Soil

Potential Problems

Generally, Spiderwort exhibits no serious insect or disease problems, which is a significant benefit for low-maintenance gardening. However, gardeners should watch for young shoots which can be attractive to snails and caterpillars; immediate intervention is necessary to protect new growth. The most common aesthetic issue across the genus is foliage sprawl or decline, particularly as summer heat sets in. While this cultivar is reportedly less prone to severe decline, aggressive mid-summer cutting back remains the best strategy to maintain a tidy appearance and promote fresh late-season growth.

Frequently Asked Questions

What hardiness zones is Spiderwort suitable for?

Tradescantia (Andersoniana Group) ‘Concord Grape’ is hardy across USDA Zones 4-7, offering excellent reliability throughout much of the temperate United States.

How large does Spiderwort grow?

This compact cultivar typically matures to a height between 0.75 and 1 foot tall, with a spread ranging from 1 to 1.5 feet wide.

What sun exposure does Tradescantia (Andersoniana Group) ‘Concord Grape’ need?

It prefers a location receiving full sun to part shade; ensure it gets adequate sunlight to maximize its prolific bloom period.

When does Spiderwort bloom?

Tradescantia (Andersoniana Group) ‘Concord Grape’ offers continuous purplish-blue flower displays primarily from May through August.

Conclusion

The Tradescantia (Andersoniana Group) ‘Concord Grape’ Spiderwort is a garden workhorse, providing long-season color and exceptional adaptability, particularly concerning moisture levels. Its unique, grape-hued blooms and relatively straightforward care routine make this perennial a winning choice for diverse garden settings. Before planting, confirm your site conditions align with its USDA Zone 4-7 range and its preference for consistently moist soil.

Companion Planting

Choosing companions for Tradescantia (Andersoniana Group) ‘Concord Grape’ should focus on plants that share its love for consistently moist or wet soil conditions. Astilbe, Japanese Iris, and various ferns thrive alongside Spiderwort, providing varied textures that complement its bold, strap-like leaves. Consider placing it near plants that bloom later in the season, as its mid-summer cleanup might leave a temporary gap; later bloomers will subsequently fill out the space.

In wetter areas, consider moisture-loving natives like Swamp Milkweed (Asclepias incarnata) or Joe-Pye Weed (Eutrochium spp.). These pairings respect the wet soil needs of the Spiderwort while enhancing the overall structure and ecological value of the rain garden or waterside planting area.

Design Ideas

The rich purplish-blue of ‘Concord Grape’ naturally lends itself to cool-toned color palettes, pairing beautifully with silver foliage or white-flowering companions. Use this Spiderwort as a mid-border plant where its height (around 1 foot) won’t obscure shorter foreground elements. In contemporary designs, its architectural form can provide structure even when not in bloom.

For a naturalized look, mass planting of Tradescantia (Andersoniana Group) ‘Concord Grape’ creates a flowing river of color in open meadow settings. Ensure pathways or seating areas are near the planting, as the fleeting nature of the individual flowers—opening at dawn and closing by evening—is best appreciated up close throughout the early summer months.