Spiderwort is a spring-blooming plant with long, strappy leaves and blue-purple buds. Native to North America, South America, and Central, it's a beloved addition to any garden thanks to its easy care and weeks-long bloom period. There are about 75 species in the Tradescantia genus, most notably T. ohiensis,, T. virginiana and T. subaspera. All species of spiderwort have similar characteristics and will hybridize in any combination. Virginia spiderwort is the plant most often cultivated for the home garden landscape.
Spiderwort is characterized by a grass-like form with leaves similar to lilies that grow to three feet in height each season. Quarter-sized flowers open in the morning and close by early afternoon, each bloom lasting just one day. Luckily, each plant produces many buds throughout spring and into early summer. The flowers attract pollinators including butterflies and are of special interest to native bees.
|Common name||Spiderwort, widow's tears|
|Plant type||Herbaceous perennial|
|Mature size||6 in.–2 ft. tall, 1–1.5 ft. wide|
|Sun exposure||Partial shade|
|Soil type||Moist but well-drained|
|Bloom time||Spring, Summer|
|Flower color||Blue, purple, pink|
|Hardiness zones||4–7 (USDA)|
|Native Area||North America, Central America, South America|
Novice and pro gardeners alike love spiderwort for many reasons, chief among them its charming continuous blooms and straight-forward care. The grassy plant grows in clumps, making it the ideal choice for edging your garden, lining a pathway, or adding early spring color to your beds. The plant thrives in moist but well-draining soil, but is otherwise unfussy, growing well in both sunny and partially shady environments and favoring a variety of soil conditions and pH levels. While spiderwort can be grown indoors or in containers with the proper care, it really is best suited to a garden environment due to its fast-growing nature and sprawling leaves. No deadheading is necessary to achieve repeated blooming on your spiderwort. However, it does tend to self-sow enthusiastically, so if you're worried about containing the spread, you can shear the plants back after their last flowering so they don't have a chance to go to seed.
Spiderwort is not overly picky about available sunlight. While the plant tends to prefer partial shade, it does well in almost any environment, so long as it gets at least a few hours of light per day and enough water if exposed to all-day sunlight. That being said, you will notice a difference in the amount and frequency of blooms depending on how much sunlight your spiderwort gets, so choose a sunnier spot if you're hoping for an especially showy plant.
Spiderwort is easily grown in almost any soil condition, so long as it is moist but well-draining—it thrives best in a humusy soil that boasts a slightly acidic pH of 5.0 to 6.0. Because the plant tends to clump and sprawl as it grows, it's best planted in the spring, four to six inches deep in the soil, with about a foot between each plant to give them ample room to grow.
While spiderwort is a drought-tolerant plant, it does best in moist soil and should be watered every few days, especially during the hotter summer months. If you live in an area with frequent summer storms, chances are your natural environment will provide enough rain to keep your spiderwort plants happy. Plants grown in containers instead of in the ground should be watered more frequently, as they're less likely to retain adequate moisture.
Temperature and Humidity
Spiderwort is not picky when it comes to its temperature and humidity conditions. It's adapted to a range of hardiness zones and can tolerate a variety of temperatures, allowing it to thrive from early spring to late summer. Because spiderwort plants like moisture, they will do fine in humid climates but do not require any added humidity if it's not naturally present in your environment.
Fertilizing your spiderwort plant is most important if you're attempting to grow the varietal indoors—you can apply a balanced liquid fertilizer once a month to any container spiderwort plants, tapering off your application as the plant goes dormant in winter. For spiderwort plants grown outdoors, the need for fertilizer is even less, and the plant can suffice on one to two applications in early spring at the beginning of its grow period. If you'd like to give your plant added nutrients throughout the summer, you can add compost to your soil mixture.
Seeds for spiderwort are available in a mixture of colors—most of the tradescantia plants available in nurseries are cultivars of Virginia spiderwort that have been developed by breeders with a focus on leaf and flower color. They include:
- Tradescantia "Amethyst Kiss": This varietal boasts purple-blue blooms that seem to glow when the sun hits them.
- Tradescantia "Concord Grape": This eye-catching mixture pairs pinkish-purple flowers with striking blue-tinted leaves.
- Tradescantia "Red Grape": The bright rose-colored flowers in this varietal are offset by silver shimmered leaves.
- Tradescantia "Sweet Kate": This bold variety has bright yellow leaves that contrast well with its saturated blue flowers.
The major drawback of spiderwort is its tendency to look ragged after its bloom period is over. The solution to this issue lies in mid-season shearing. This practice serves two purposes: First, it prevents spiderwort from self-sowing and becoming weedy. Second, shearing the plant back by one-third (leaving around eight to 12-in. stems) or de-leafing to new growth will reinvigorate the plant, increase your chance. of late-season blooms, and make it look more presentable for the rest of the season.
Spiderwort plants will readily self-seed so if you want to increase the number of plants in your garden, you can forego the mid-summer shearing and let the plants go to seed. Plants may also be started from seed, however they will require a period of cold moist stratification. This can be accomplished by placing the seed in a refrigerator for two to four weeks prior to sowing. The easiest way to propagate spiderwort may be to simply divide large clumps in the fall or very early spring.
Although the incidence is low, the leaves of the spiderwort plant can cause contact dermatitis and other skin irritations in gardeners who are sensitive.