Last Updated on September 15, 2022 by Plant Mom Care
Torenia, often known as wishbone flower or Florida pansy or bluewing, is a genus previously classified under the Scrophulariaceae figwort family but now classified under the Linderniaceae family. These plants are indigenous to the Indochina Peninsula and subtropical and tropical Asia.
These plants can grow wild and easily naturalize in tropical settings. The plant also tends to reseed itself in warm locations. However, it is not vigorous enough to be termed invasive in the US. The genus Torenia is named for Reverend Olof Toren, a Swedish chaplain in the 1700s, who was based in India and China.
The leaves are light green, ovate shaped with jagged edges, and are somewhat hairy. The plant can grow 6 – 12 inches high. Slightly fragrant trumpet-shaped flowers form in clusters above the leaves. The upper 2 petals are fused, and the lower 3 petals are partially fused, with the lowest petal forming a “tongue”.
The 2 stamens are fused at first at the anthers before splitting when ready to be pollinated, which makes them look like a wishbone, where the common name comes from. The calyx has a distinct fluted shape resembling a tiny starfruit. The seeds are tiny and can be collected from spent flowers.
These plants can bring color to shadier parts of the garden. Unlike several many annual flowering plants, these plants can tolerate partial shade. The flowers come in many colors, with the main species displaying dark blue-purple and pale violet colors with yellow marks. Colors can range from shades of white, blue, yellow, pink, and purple. Many F1 and F2 hybrids have been developed during recent years.
Start these plants in spring after winter as they are annuals and die at the touch of frost and grow rapidly and flower profusely from early summer until autumn. These plants are deer-resistant and attract hummingbirds.
These plants are excellent for cultivating in borders, beds, groundcover including containers or hanging baskets. Plant them roughly 6 inches apart to get the best display. Other than properly watering the plants, they don’t need much maintenance.
Torenia Light Requirements
The ideal spot for these plants is where they get early morning sun and plenty of afternoon shade. In hot climates, choose a more shaded location as they don’t do well in full sun, causing their foliage to turn brown or fade and hindering the plants from flowering.
These plants need moderate and consistent moisture – keep the soil damp, but ensure the plants are not water-logged.
These plants cannot handle high humidity and prefer moderate levels of humidity with plenty of ventilation.
They grow best in temperatures of 65 – 75°F. They can tolerate cool temperatures, although the slightest hint of frost will kill them. They can benefit from mulching to cool their roots in warm climates.
They prefer rich, loamy soil with slightly acidic or neutral soil pH. Good drainage is necessary to avoid root rot. Soil quality can be improved by adding some compost or slow-release fertilizer when planting. Consider adding vermiculite or gravel to ensure good drainage.
Since these plants are annuals, repotting isn’t necessary. Be warned that these plants don’t handle transplanting well. If purchasing these plants from nurseries/garden centers, ensure they are growing in peat pots. This lets you plant them into containers or your garden without distressing the roots.
Propagation by seeds
Seeds can be started 6 or 8 weeks indoors before spring is predicted for your area as mentioned, these plants don’t transplant well, so use biodegradable peat pots or coir pots that can be easily planted with the seedlings. In warm climates, you can direct-seed into planting sites outdoors.
Keep the seeds exposed and uncovered as light is needed for germination. Keep watering judiciously until the seeds germinate. When transferring young plants outdoors, slowly expose them to outdoor conditions to avoid shock. After the transfer, pinch the plants down when they are 3 inches high to promote bushier foliage.
Propagation by cuttings
Take healthy 6-inch long stem cuttings with a leaf node at the end from where roots will form. Leave just two leaves on the tip of the cuttings and place them in water. Once roots start to appear, transplant the cuttings into biodegradable peat pots or coir pots full of soil, and water them. Take the new plants outside for long periods (about a week) to acclimatize them to outdoor conditions before transplanting them in the ground or into a container.
To keep plants healthy, add balanced, all-purpose, or flowering fertilizer every month throughout their growing season. Either liquid fertilizer or slow-release fertilizer can be used but follow the instructions, usually a tablespoon of liquid fertilizer to each gallon of water, twice monthly.
Deadheading blooms isn’t necessary, although it will help encourage more foliar growth and flowering. Spent flowers can be removed to harvest seeds. However, if plants look leggy or scraggly, they can be trimmed down to around half their height. Since these are annuals that die when conditions become frosty, it’s no use to overwinter them in cold climates. Start planting seeds indoors during winter to be ready to plant when spring comes around.
Torenia Common Problems
While these plants don’t face any major issues with disease, they are susceptible to fungal infections like powdery mildew that discolor and damage foliage and stems. Avoid over-watering and enough air circulation to help prevent fungal problems.
A few common pests, like aphids and whitefly, can prey on these plants. Aphids produce a sticky material that they leave behind when they attack the plants. Both can be controlled and treated using insecticidal soap and/or neem oil.
The main problem for these plants not flowering is moisture, heat, and humidity. They don’t like water-logged soil and might not flower when they are overwatered or if the soil doesn’t drain well. They usually grow well with moderate temperatures and average levels of humidity, as hot or humid conditions can stunt their growth.