Ornamental · Linderniaceae
Wishbone Flower
Torenia fournieri
Plant it in the shade, keep it watered, and wishbone flower rewards you with bloom from summer to frost.
Partial shade
Every 2–4 days
64–86°F · 18–30°C
USDA 2–11
Overview
Wishbone flower is a shade-garden standout, and the name is worth a closer look: two stamens arch and meet inside every bloom, forming a tiny wishbone. It throws out cool blue, purple, pink, and white flowers and keeps them coming from early summer straight to frost. Fill a dim corner with this and watch it come alive with color.
While the sun worshippers hog the bright beds, this one dives happily into dappled light and part to full shade. That opens up all kinds of spots: a border along a fence, the shady north side of the house, a pot on a covered porch. Gardeners in hot regions get the best results by handing it morning sun and letting it duck the fierce afternoon.
Best of all, it delivers big and asks for little in return. Keep the soil moist, pinch it every so often for a full shape, and it flowers on with zero deadheading. Just stay on top of drainage, because soggy roots are the one thing that will slow this go-getter down.
Care
The short version: plant it in part to full shade out of the hot afternoon sun, keep the soil evenly moist at about 1 to 1.5 inches of water a week, give it rich ground that drains fast, and pinch it now and then to keep it packed with growth.
Light
Lean into its shade-loving nature and set it in part to full shade or dappled light. In hot climates, pair morning sun with afternoon shade and it hums along. Push it into too much direct sun, though, and the stems stretch while the flowers taper off.
Water
Keep that soil evenly moist and never let it run dry between drinks. Plan on about 1 to 1.5 inches of water a week, and spread mulch to hold the roots cool once the heat cranks up.
Soil
Set it up in rich, organic ground that stays moist but drains fast. Aim for a slightly acidic pH of 6.0 to 6.5, and nail the drainage above all, since that is the one thing it will not shrug off.
Temperature
It thrives across a generous span, from about 64°F to 86°F (18°C to 30°C). Frost stops it cold, and the harshest summer heat rolls off easier when you back it with shade and steady moisture.
Humidity
Ordinary outdoor humidity is plenty, so skip chasing a number. Keeping air on the move counts for far more, because still, damp air in the shade is exactly what powdery mildew jumps on.
Feeding
Work a complete slow-release fertilizer into the bed at planting and it fuels the plant for a long run. Feed again at about 6-week intervals through the growing season whenever the plants signal they want more.
Pruning
Pinch the new growth every so often and the plant packs in bushy, compact growth instead of stretching out. Forget deadheading entirely, since the flowers clean themselves up and drop on their own.
Size & spacing
These stay compact, topping out at 6 to 18 inches (15 to 46 cm) tall and 6 to 9 inches (15 to 23 cm) wide. That neat footprint makes them a winner for edging, containers, and the front of a shaded bed.
When to plant
Wishbone flower runs on the warm season and cannot take a frost, so its show fills the stretch between the last spring frost and the first one in fall. Get seeds going indoors in late winter, move the plants out the moment the cold breaks, and they flower from early summer right up to frost. Time it well and the payoff runs for months.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Start seeds indoors 6 to 8 weeks before the average last frost date.
- Plant: Transplant outdoors after danger of frost has passed, around mid to late April in many regions.
- Harvest: Blooms from early summer (about June) until first frost.
Hardiness
USDA hardiness zones: 2–11
Temperature: down to -46°C
Troubleshooting
Wishbone flower keeps trouble to a minimum, and what does crop up almost always ties back to soggy soil or too much sun. Spot the early signs below and you can jump in fast, long before a plant fades. Match the symptom, then act and watch it recover.
A plant caving in over soft, dark roots
Wilting, yellowing, and a full collapse over dark, mushy roots spell root rot, and it sets in when the soil stays wet or drains too slowly. Dig at the base and the roots come up soft and foul instead of firm and pale. Move fast: dial back the watering, work in something that drains better, and pull any plant already turned to mush before it drags down the rest.
Fix:
- Improve drainage and reduce watering frequency
- Remove and discard severely affected plants
Long, stretching stems and fewer blooms
Stems that shoot up long while the flowers thin out mean the plant is grabbing too much hot afternoon sun, often with no pinching to rein it in. Shift it to morning light with afternoon shade, then pinch back the new growth to drive it back into that full, flower-loaded shape.
Fix:
- Provide morning sun with afternoon shade
- Pinch back new growth to encourage bushiness
White powder spreading over the leaves
That dusty white film on the upper leaves is powdery mildew, a fungus that pounces where shade meets still, damp air. Spread the plants out, get air moving through them, and water at the base to keep the leaves dry. Stay ahead of it and the planting bounces right back.
Fix:
- Improve air circulation and spacing
- Avoid wetting foliage when watering
Toxicity
Here is more good news for eager growers: wishbone flower is non-toxic and safe around pets, livestock, and children. It never lands on the ASPCA's list of plants that harm cats or dogs, and no part of it holds a toxin. Plant it anywhere the whole household roams.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
Great news for cat owners: it is safe, and a nibble will not poison a cat, though almost any plant can hand a sensitive one a brief, mild stomach upset.
Dogs None
Dogs are in the clear, since the plant packs no toxins. A pup that grazes the leaves or flowers comes to no harm.
Horses Safe
Horses can graze right alongside it without any risk, because nothing in the plant will hurt them.
Rabbits Safe
Rabbits browse it safely and take no harm at all, and they may well treat a planting as an easy snack.
Livestock Safe
Cattle, goats, and sheep can graze near it with zero toxic risk in play.
Birds Safe
Wild and pet birds stay perfectly safe around it, since no part of the plant can harm them.
People Safe
People are safe too, so kids can dive right into the blooms, just keep in mind it is grown for the show, not for the plate.
Varieties
Named series abound, but a handful turn up again and again at the garden center. Grab these by name and hit the ground running.
Kauai
A compact series that cranks out dense, heavy bloom in part shade.
Duchess
A compact series that jumps into bloom early and shows off larger flowers than most.
Little Kiss
A pint-sized mounding type that shines in containers and along the front of a bed.
How to propagate
Wishbone flower springs up easily from seed, and that is the go-to route for launching a fresh batch every spring.
SeedEasy
Start indoors 6 to 8 weeks before last frost, or direct sow after frost danger passes. · Several weeks to transplant size after germination.
Seed is the easy, rewarding way to raise wishbone flower for spring beds. Sow it indoors 6 to 8 weeks ahead of the last frost, or sow straight outside once the cold clears, then give the seedlings several weeks to bulk up to transplant size.
Myths
You have to deadhead wishbone flower to keep the blooms coming.
Skip it entirely, because the spent flowers take care of themselves. This plant is self-cleaning and pumps out bloom on its own from spring all the way to frost.
Torenia will only flower well with full sun.
Not so, because it flowers heavily in part to full shade, one of the few annuals that can. In a hot climate it even prefers afternoon shade, where full sun would just wear it down.