Ornamental · Commelinaceae
Spiderwort
Tradescantia virginiana
Thriving in sun or shade, spiderwort throws out fresh three-petaled blooms morning after morning.
Full sun
USDA 4–9
2–3 ft · 0.5–0.9 m
Overview
Spiderwort earns its place fast. This tough, clump-forming perennial from eastern North America runs off a long parade of three-petaled flowers through late spring and summer, and it keeps the show going. Each bloom lasts a single morning and fades by afternoon, but the plant fires up a new one the next day. Grassy, arching foliage rounds it out, and it takes hold almost anywhere, from a sunny border to a shaded woodland edge.
Here is where it really wins you over: its reach across light and soil. Full sun brings the heaviest flowering, yet it powers along in partial or even deep shade, and it takes clay, sand, chalk, and wet ground in stride where pickier plants give up. Hardy to zone 4, it bounces back every year and asks almost nothing once it digs in.
One habit to plan for keeps it honest: a midsummer slump. Once the first big flush winds down, the clump tends to sprawl and brown, and heat pushes it along. Hit it with a hard cutback, though, and fresh growth surges back, often with a second wave of flowers to close out the summer.
Care
The short version: get spiderwort into moist, fertile soil anywhere from sun to shade, keep the water going through dry spells, and cut the whole clump back hard after the first flush to spark fresh new growth.
Light
Spiderwort pumps out the most flowers in full sun, but it keeps performing in partial and even deep shade. Where summers crank up the heat, hand it a little afternoon shade to keep it standing tall and take the sting out of the midsummer slump.
Water
Keep the soil consistently moist to occasionally wet, because this plant leans hard toward damp ground. Water it through every dry spell, and pour it on right after a cutback, to drive up a rush of fresh basal growth.
Soil
It digs into just about anything, clay, loam, sand, or chalk, and even wet ground or soil near black walnut. Aim for fertile, moist but well-drained soil to get the best from it, and it rolls with a wide pH from 6.0 to 8.0.
Temperature
This one is genuinely tough. It powers through cold down to about -29°F (-34°C) and takes summer heat up to 95°F (35°C), though that heat is exactly what sets the foliage sprawling and browning.
Humidity
Ordinary outdoor humidity is plenty, so skip chasing a number. Airflow is the real win here, since crowded, damp clumps are where rust and leaf spot dig in.
Feeding
This vigorous perennial barely asks to be fed. Give it a light feed of balanced fertilizer or compost as growth takes off in spring and stop there, because overfeeding just pushes soft, floppy stems.
Pruning
Deadhead the spent flowers to drive out a second late-summer flush. Once the foliage sprawls or browns after the first flush, shear the stems back hard, then cut the whole plant to the ground when the season wraps up.
Repotting
Out in the garden it never gets potted on, but it thrives on a good split. Lift and divide the clump every 3 to 4 years to keep it charging, especially once the center thins out or the flowers start to slack off.
Size & spacing
Expect a clump to shoot up 1.5 to 3 feet (46 to 91 cm) tall and spread 12 to 18 inches (30 to 46 cm) wide. Give each plant that much room so air rips through and the foliage stays clean and healthy.
When to plant
Spiderwort runs on the seasons, so timing it is easy. Plant it out in spring once frost clears, or drop container-grown plants in through autumn, and the flowers roll in from late spring through early July, with plenty of plants circling back for more into late summer.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Plant: Spring after frost; container plants can also be set out in autumn
- Harvest: Late spring through early July (May-July), often reblooming into late summer; cultivars can flower June-September
Hardiness
USDA hardiness zones: 4–9
Temperature: down to -34°C
Troubleshooting
Spiderwort keeps trouble to a minimum, and nearly everything that crops up is cosmetic. A midsummer flop, a bit of slug damage, and the odd rust spot make up almost the whole list. Match your symptom below and jump on it before it spreads.
Foliage flops and browns off as midsummer heat hits
This is just the plant's natural slide after flowering, and summer heat plus dry soil speed it right along. Once the main flush burns out, the clump opens up and the leaves run out of steam. Shear the stems back hard, water through any dry stretch, and fresh basal growth charges up to drive it into fall.
Fix:
- Shear or cut the stems back hard after flowering
- Water during dry spells to encourage fresh basal regrowth
- Allow the plant to reflush in late summer and fall
Ragged holes torn through the fresh new shoots
Chalk this one up to slugs and snails, which zero in on the soft spring shoots and leave slime trails right beside the chewed edges. They hit hardest in damp, shady corners. Head out after dark and pick them off by hand, clear the wet debris they hunker under, and set out traps or barriers if they keep pushing in.
Fix:
- Hand-pick slugs and snails, especially in the evening
- Reduce moist hiding spots and debris near the crown
- Use slug traps or barriers if damage is heavy
Orange-brown pustules and spots peppering the leaves
Let a clump get damp and crowded and rust and fungal leaf spot move right in, throwing up orange-brown pustules or scattered blotches. Strip off the marked leaves and bin them, then thin and cut back the clump to get air moving. Keep water off the foliage and you shut most of it down before it starts.
Fix:
- Remove and dispose of affected foliage
- Cut back and thin congested clumps to improve airflow
Toxicity
Spiderwort lands as a skin irritant rather than a real poison, so it is easy to grow with a little care. The sap can kick up an itchy rash on bare skin, so grab gloves before you cut it back or divide it, and a pet that chews a leaf might get a mildly upset stomach. Keep the nibblers off it, but shrug off a stray bite.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds · People
Cats Mild
A cat that chews the leaves or stems can pick up a mild bout of stomach upset, and the sap may leave its mouth or skin irritated. Watch for drooling or pawing at the face.
Dogs Mild
A dog that nibbles the foliage might drool or run through a brief bout of mild GI upset. The sap can also redden the skin around the muzzle where it lands.
Horses Caution
The ASPCA flags the genus for horses, with skin irritation the main worry. Keep grazing horses from making a habit of the foliage.
Rabbits Caution
The irritant sap can leave a rabbit with a sore mouth and some stomach upset, so it is not a green worth handing over.
Livestock Caution
Goats, sheep, and cattle mostly steer clear, but a mouthful of the sappy stems can irritate the mouth and gut. A stray nibble, though, is no big deal.
Birds Caution
That same irritant sap makes spiderwort a poor pick around pet birds, which can react to even small amounts.
People Caution
The sap acts as a skin allergen and can flare up an itchy rash, so pull on gloves before you cut the plant back or divide it. No part gets eaten, so the risk rides on your skin, not your stomach.
Sap can cause contact dermatitis and is a skin allergen; wear gloves and protective equipment when cutting back or dividing.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
Poison Control: (800) 222-1222
Canada
Poison Centres: 1-844-764-7669
Varieties
Garden spiderwort delivers a tight lineup of named selections, split mostly by flower color and how bright the leaves run. These are the standouts to chase down.
'Sweet Kate' (syn. 'Blue and Gold')
Deep blue-purple flowers blaze against bright golden-chartreuse foliage on a compact plant of 12 to 24 inches (30 to 60 cm) tall.
'Concord Grape'
Rich grape-purple flowers ride above cool blue-green leaves.
'Zwanenburg Blue'
A vigorous Andersoniana Group selection that pushes out large, deep blue-purple flowers.
'Satin Doll'
Soft pink flowers pop on a tidy, compact plant.
'Billberry Ice' / white-flowered forms
Clear white, three-petaled flowers light up a shady spot.
How to propagate
Multiplying spiderwort is a genuine pleasure, and it could hardly be simpler. Split an established clump, or let the plant fling a little of its own seed around the garden and gather up the volunteers.
DivisionEasy
Spring, or in autumn after flowering · Reaches full size in 1-2 years
Division is the fastest track to more plants, and spring or autumn once flowering ends is the moment to go. Lift a congested clump and pull or cut it into sections, each one loaded with its own roots and shoots. Replant them and they hit full size within 1 to 2 years, so keep splitting every few years to drive the parent plant on.
SeedModerate
Sow seed in spring; plants also self-sow readily in the garden · 1-2 years to mature, flowering-size clumps
Spiderwort scatters its own seed like a champ, so seed-grown plants basically run themselves once sown in spring, reaching flowering size in 1 to 2 years. Named cultivars are the exception, since they will not come true from seed and are better divided. Snip back the spent flower stems to rein the self-seeding in before it takes off.
Myths
Garden spiderwort is just the trailing inch plant houseplant under another name.
Not a chance. Tradescantia virginiana and the x andersoniana garden hybrids are cold-hardy, clump-forming border perennials that charge back down to zone 4. The tender tropical trailers sold as houseplants, T. zebrina and T. fluminensis, run in a completely different lane. The hardy garden spiderworts hold tight as clumps, while tropical T. fluminensis turns invasive across the warm southern states and is one to skip.
Spiderwort has to have full sun to really perform.
Full sun does drive the heaviest flowering, but the plant powers on in partial and even deep shade. In hot-summer regions a little afternoon shade actually gives it a boost, taking the edge off the midsummer flop.