AT HOME WITH THE HOYA : Distinctive Waxy Blossoms Dress Up Its Vining Stems

Appearing to be made of wax, not just coated with the stuff, the flowers of the various hoyas are a plant oddity. Even the stems and leaves are as waxy as a votive candle. This is a climbing plant that can attach itself fast to walls or other supports with clinging rootlets. The queerly shaped flowers hang like candelabra from the twining stems so they are plainly visible.

It also has curious kin. A hoya and a milkweed would not seem to be members of the same plant family--the milkweeds, or Asclepiadaceae . But when examined closely, the small blossoms are similarly structured, with that distinctive, identifying five-pointed star at the center of each blossom.

In warm weather, hoyas grow quickly, and the vining stems may be found in unexpected places--wrapped around a chair back, clambering along a curtain rod or furtively creeping into another plant’s territory. They can send out six-foot stems but they won’t take over the house since they don’t get much larger than that.

Because they are shy of roots, most plants need only a six-inch pot. Don’t rush to repot. A hoya flowers best when it’s pot-bound. And, don’t remove the flower stalks (peduncles), since new inflorescences form from these.

Hoyas need a warm spot in your home and strong, indirect light (no direct midday sunlight). Use a potting mix that is rich and loose. Water should run right through the soil-filled container and the soil should never be soggy. If it is, repot the plant in a more porous mix. Withhold water until the mix is moderately dry. That’s particularly true in winter when the top of the soil should feel dry to the touch. Fertilize lightly every six weeks or so during the warmer months; these plants are not the hungry sort.

Some experts suggest an occasional misting of the leaves to increase the humidity. That’s also a good time to check the plant for pests. Although spider mites and scale can be a problem (spray them outdoors with malathion), mealybugs are the most common and most virulent pests. Check for these little cottony creatures and try to catch them before they become too numerous. Dab each of them with a cotton swab dipped in rubbing alcohol--or vodka, if that’s handier. Repeat twice weekly until no sign of their presence remains.

One other creature, so colorful that you may not consider it a pest but an ornament, is a brilliant golden aphid that seems to inhabit only hoyas. Aphids appear overnight in late summer, in small herds, then leave as mysteriously as they came. Should you find their presence objectionable,they are easily, if somewhat stickily, removed.

The one hoya usually available is Hoya carnosa and its cultivars. Some of these cultivars include:

H. carnosa ‘Compacta’--A less viny plant with leaves that grow much closer together than other hoyas.

H. carnosa ‘Exotica’--This cultivar has leaves that are variegated with red and yellow.

H. carnosa ‘Krinkle Kurl’--A popular hoya also known as the Indian rope plant. Its leaves are unusually distorted, folded, curled and crowded along drooping stems.

H. carnosa ‘Variegata’--As the plant’s name implies, this hoya has variegated leaves. In this instance, variegation takes the form of white-edged, light-green leaves.

H. bella is another wax plant worth seeking out. It’s smaller and more delicate than H. carnosa . Slender branches grow upright at first, then cascade to the floor.