Torenia, also known as wishbone flower, is a genus of flowering annuals in the snapdragon family. The wishbone-shaped flowers bloom during late summer and early fall and can be yellow, pink, purple or white, depending on the variety. Torenia is native to Asia and Africa, but can be easily grown in any temperate region with the proper care and maintenance.
Plant torenia as soon as cold weather ends in a location that receives full sunlight. Spread ½ inch of clean sand over the planting site and use a garden spade to incorporate it into the soil to increase drainage.
Dig a hole twice as wide as the root ball and of equal depth. Place the plant directly into the hole and gently refill with soil. Water thoroughly to collapse any air pockets and to bring moist soil into contact with the roots. Space plants at least 8 inches apart.
Spread a 1-inch layer of mulch around the soil surrounding the torenia plants. Begin the mulch about 4 inches away from the stems to allow room for growth. Refresh the layer of mulch as often as necessary to keep it about 1 inch thick at all times.
Water torenia three times per week during the first month of growth. Reduce the frequency of watering to once per week after the roots are established. Do not allow the soil to become soggy at any time, or the roots may rot.
Feed torenia plants once per month until the plant dies back in late fall using a balanced 10-10-10 NPK fertilizer. Water both before and after applying fertilizer to prevent root burn. Follow the manufacturer's directions for proper application and dosage.