Spiderworts can be compared to daylilies and dayflowers — each blossom lasts only one day. The common name refers to the many glistening hairs on the sepals and the buds. They resemble a spider’s nest of webs, especially when covered with dew (“wort” is an old English word for plant).
Description of spiderwort: Spiderworts are weak-stemmed plants that grow up to 1 foot long. They produce a watery juice and have folded, strap like leaves. The 3-petaled flowers, opening at dawn and fading by mid-afternoon, are surrounded by many buds.
Spiderwort ease of care: Easy.
How to grow spiderwort: Spiderworts want a good, well-drained garden soil in full sun or partial shade. In dry summers, they will need extra water. In too-rich soil, they grow quickly and tumble about. Even the newest types can become floppy by midsummer — so when flowering is through, cut the plants to the ground, and they will often flower again.
Soil: Spiderwort prefers a slightly acidic soil pH, in the 5.8 – 6.8 range.
Planting: You can start with plants or seed, but not all cultivars are available from seed. Start the seed indoors, in early spring. Barely cover seed with soil and be sure to keep it moist. Seed should germinate within 2-3 weeks. Move seedlings into larger pots and slowly harden off, before transplanting outdoors.
Spiderwort plants will self-seed freely, sometimes to the point of becoming a nuisance. They are easy to pull out and at the end of the season shearing will cut back on the spread of seed.
These plants are also easy to divide and you can do this in either the spring or fall. I prefer to do it in the spring, so that they have time to reestablish.
Uses for spiderwort: Although fine in the sunny border, the newer spiderworts are best in areas of open shade, especially under tall trees.
Spiderwort related species: Tradescantia virginiana is the original species and is still found in many old country gardens. The flowers are usually 1 inch wide, violet-purple, and often very floppy.
Spiderwort related varieties: ‘Red Cloud’ has deep rose-red flowers; ‘Zwanenberg’ has very large, blue flowers; ‘Snow Cap’ is pure white; and ‘Valor’ is a deep red-purple. All grow to a height of 20 inches. ‘Sweet Kate’ has yellow leaves and deep blue flowers. ‘Concorde Grape’ is deep violet blue.
Scientific name for spiderwort: Tradescantia x Andersoniana
Overview and Description
Tradescantia is a genus of perennial flowers. Many are tropical creeping or hanging plants that are often grown as houseplants or used as groundcovers in warm climates. Spiderwort, Tradescantia virginiana, is a very hardy North American native that is widely grown for its weeks long, mid-spring bloom period.
Spiderwort has a kind of messy, grass-like form punctuated with quarter-sized flowers that last only one day.
Luckily they produce many of them, in a leisurely succession. As the petals fade, they become almost translucent, giving them their other common name, Widow’s Tears.
- Leaves: The blade-like leaves are lanceolate and grow to 12 in. or longer.
- Flowers: The 3-petaled flowers are most popular in clear blue, but there are varieties that bloom in white, pink and purple. They tend to close in the afternoon sun and only last for a single day.
Botanical Name Tradescantia virginiana
Common Name: Spiderwort, Virginia spiderwort, Widow’s Tears
Hardiness Zone Spiderwort is reliably perennial in USDA Hardiness Zone 4 – 9.
Sun Exposure For the most abundant blooms, plant your spiderwort in full sun and moist, well-draining soil. If you can’t provide moist soil, you may have better success planting them in partial shade. You will sacrifice a little blooming, but you’ll barely notice.
Mature Size Mature plants reach a height of 12 – 24 in. and spread to 18 – 36 in. You will generally divide them, before they reach 36 in.
Bloom Period You will get a good 3 months of blooms (May – July) from your spiderwort plants. No deadheading is necessary to get this repeated blooming. If you are worried about them self-seeding too aggressively, you can shear them back after their last flowering.
Suggested Varieties Seed for Tradescantia will most likely be a mix of colors. Most of the Tradescantia plants available in nurseries are cultivars of Virginia spiderwort. Plant breeders have really been focusing on leaf color and the contrast of leaf and flower color.
- Tradescantia ‘Amethyst Kiss’: The purple-blue virtually glow when the sun hits them.
- Tradescantia ‘Concord Grape’: Pinkish-purple flowers are set against blue tinted leaves.
- Tradescantia ‘Red Grape’: Bright rose-colored flowers are offset by silver shimmered leaves.
- Tradescantia ‘Sweet Kate’: Has bright yellow leaves that contrast well with the clear blue flowers.
Design Suggestions The major drawback of spiderwort is its tendency to look ragged after its bloom period. Since it is an early bloomer, pair it with plants that will distract, but complement. The wide leaves of Heuchera and Bergenia are good choices. If you are growing them in partial shade, primrose makes a good partner.
Although spiderwort will tend to fade into the background after blooming, let them shine in spring by using them as edging along paths, in the cracks of stone walls or massed as a groundcover under trees. My favorite use is to allow it to naturalize in a woodland setting.
Maintenance: The main effort required to grow spiderwort will be a mid-season shearing. This serves 2 purposes. First, it prevents them from self-sowing and becoming weedy. Secondly, spiderwort declines considerably in the heat of summer, after flowering. Shearing the plants back by 1/3 or de-leafing to new growth will reinvigorate the plants and make them look a lot more presentable, for the rest of the season.
Pests & Problems: There are a few leave spotting diseases that can befall spiderwort, but they are not the norm. The biggest pest will be snails and slugs, that enjoy the same moist soil spiderwort prefers. Young plants are most susceptible. Otherwise spiderwort is virtually pest free and deer resistant.