Hoya kerrii

Sweetheart hoya is an evergreen, epiphytic, vining herbaceous perennial in the dogbane family (Apocynaceae). The specific epithet honors Irish plant explorer Arthur Francis George Kerr (1877–1942), who collected plants in Thailand and Southeast Asia.

The sweetheart hoya needs warm and humid locations. Temperatures between 65 and 80 Fahrenheit are ideal. Lower temperatures can slow the plants' growth and flowering.  Placing it in a more humid room of your home, such as the kitchen or bathroom, can benefit the plant. Watering should be done with room-temperature water, as cold water can send the plant into shock. The container should provide good drainage to allow the plant to dry somewhat between watering. Support this climbing plant with florist wire to train it on a trellis or place it in a hanging container and allow the plant to cascade. Its long, bare, twining stems should not be cut back during plant maintenance. These stems precede the formation of new leaves or flowers. The flowers emit their fragrance at night.

The heart-shaped leaves of this species make it a popular houseplant, especially around Valentine’s Day. They are often sold as a single, rooted leaf; however, those cuttings are not likely to grow well unless a bit of the stem tissue was included with the leaf when it was cut. This species can be shy to flower when young. The flowers, when they appear, produce copious amounts of reddish-brown nectar, which drips from the flowers and can stain fabrics, walls and furnishings. Either remove the flowers or place the plant in a space where the nectar stains are not a problem.

Sweetheart hoyas can be grown as specimen plants or as hanging basket plants.

Insects, Diseases, and Other Plant Problems:  Insects affecting this plant include aphids, spider mites and mealybugs. If the container does not keep the plant root-bound, it may hold excess water, which can lead to root rot. Overwatering can also inhibit the plant's ability to flower. Thinning, brown or wrinkled leaves can mean that the plant is being allowed to dry too much between watering.  

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