So how did such a lovely plant get such an unusual name? While no one may know for certain, some people think the plant was named for the way its flowers hang down like spiders. Others believe it comes from its medicinal properties, as it was once used to treat spider bites. Regardless of how the plant got its name, spiderwort is well worth having in the garden.
About Spiderwort Flowers
The three-petaled spiderwort flowers are usually blue to purple, but may also be pink, white, or red. They only remain open for a day (blooming in morning hours and closing at night), but the multiple flowers will continually bloom for up to four to six weeks in summer. The plant’s foliage consists of arching grass-like leaves that will grow about a foot or two (0.5 m.) in height, depending on the variety. Since spiderwort plants grow in clumps, they’re great for use in borders, edging, woodland gardens, and even containers. You can even grow spiderwort as an indoor plant if garden space is limited.
Growing Spiderworts
Growing spiderworts is easy and you’ll find the plants to be quite resilient. They’re hardy in USDA plant hardiness zones 4-9 and will tolerate more than what one would expect. Spiderworts typically grow in moist, well-drained, and acidic (pH 5 to 6) soil, though I have found the plants to be quite forgiving in the garden and tolerant of many soil conditions. Spiderwort plants do best in partial shade but will do equally well in sunny areas as long as the soil is kept moist. Spiderworts can be grown from purchased plants or propagated through division, cuttings, or seed. Plant them in spring about 4 to 6 inches (10-15 cm.) deep and 8 to 12 inches (20.5-30.5 cm.) apart. Stem cuttings in summer or fall will easily root in the soil. Seeds can be sown outdoors in either fall or early spring and should be lightly covered. If starting spiderwort seeds indoors, do so about eight weeks prior to transplanting outside. It should take anywhere from 10 days to six weeks for germination to occur. Hardened seedlings can be transplanted outdoors about a week after the last spring frost.
Spiderwort as an Indoor Plant
You can grow spiderwort indoors too as long as suitable conditions are given. Provide the plant with either a soilless mix or loam-based potting compost and keep it in bright filtered light. You should also pinch out the growing tips to encourage bushier growth. Allow it to spend warm spring and summer days outdoors, if feasible. During its active growth, water moderately and apply a balanced liquid fertilizer every four weeks. Water sparingly in winter.
Care of Spiderwort Plants
These plants like to be kept fairly moist, so water regularly, especially if you’re growing them in containers. Cutting the plants back once flowering has ceased can often promote a second bloom and will help prevent re-seeding. Cut the stems back about 8 to 12 inches (20.5-30.5 cm.) from the ground. Since spiderwort is a vigorous grower, it’s probably a good idea to divide the plants in spring every three years or so.
