Hoya care guide

Hoyas are vining plants with thick, waxy leaves and clusters of star-shaped flowers that look like they were made of porcelain. Many smell sweet at night. They grow slow, live long, and are safe for cats and dogs.

There are hundreds of hoya species. The care below works for the common ones. Thin-leaved and fuzzy types want a little more water and humidity.

Light

Give hoyas bright, indirect light. A spot right next to an east window is ideal. A few hours of gentle morning sun helps them bloom.

They survive in medium light, but they seldom flower there. Leaves that turn red or pink are getting a lot of light. That is fine unless they start to look bleached.

Water

Most hoyas store water in their thick leaves. Water when the soil is almost dry all the way down. Water until it drains, then empty the saucer.

Thick-leaved types, like Hoya carnosa and Hoya kerrii, can go dry for a while. Thin-leaved types, like Hoya linearis, need water a bit more often.

Soft, wrinkled leaves mean it is thirsty. Yellow, soft leaves with wet soil mean too much water. Read how to tell if a houseplant is overwatered or underwatered.

Soil and potting

Hoyas grow on trees in the wild, so their roots want air. Mix potting soil, orchid bark, and perlite in equal parts.

Hoyas bloom best when snug in their pot. Repot only every two to three years, when roots fill the pot. Go up one small size. See how to repot a houseplant step by step.

Humidity and temperature

Average room air is fine for thick-leaved types. Keep them between 16 and 27°C (60 and 80°F), away from cold windows and heat vents.

Feeding

Feed monthly in spring and summer with a balanced liquid fertilizer at half strength. Skip fall and winter.

Pruning

Trim long, bare vines to keep the plant full. Cut just above a leaf.

Never cut off the flower spurs. These are short, stubby stems where flowers grow. Hoyas bloom from the same spurs year after year. Let old flowers fall off on their own.

Getting it to bloom

Hoyas often take two to three years to bloom. Older, rootbound plants bloom more. To help it along:

1. Give it bright light, with some gentle direct sun.
2. Keep it snug in its pot.
3. Let the soil dry between waterings.
4. Leave the spurs alone.
5. Do not move it once buds form. A move can make buds drop.

The flowers drip sticky nectar. Put something under the plant if it blooms over a nice floor.

Propagation

Cut a piece of vine with at least two nodes and a few leaves. Remove the lowest leaf. Set the bare node in water, damp sphagnum moss, or a mix of perlite and soil. Roots grow in two to six weeks.

A single heart-shaped Hoya kerrii leaf sold in a little pot can root, but it often never grows a vine. A cutting needs a piece of stem with a node to grow.

Problems

What you see	Most likely cause
No flowers	Too little light, a young plant, or spurs cut off
Soft, yellow leaves, wet soil	Too much water
Wrinkled, limp leaves	Too dry
Buds drop before opening	The plant was moved, or the soil dried out
Long, bare vines	Not enough light
Red or pink leaves	Lots of light. Healthy if they stay firm.

Pests

Mealybugs love hoyas. They hide where leaves meet the stem and inside the flower spurs. Dab them with rubbing alcohol on a cotton swab. Aphids can show up on new growth. Fungus gnats mean the soil stays wet too long. Read how to get rid of fungus gnats in houseplants.

Pet safety

The ASPCA lists the wax plant as non-toxic to cats and dogs. A pet that eats a lot of leaves can still get an upset stomach.

Varieties

• Hoya carnosa is the classic wax plant, with pink flowers and green leaves.
• ‘Krimson Queen’ has green leaves with cream and pink edges.
• ‘Krimson Princess’ has leaves with cream and pink centers.
• ‘Compacta’, the Hindu rope plant, has curled, crinkled leaves along rope-like vines.
• Hoya kerrii, the sweetheart hoya, has heart-shaped leaves.
• Hoya pubicalyx grows fast and has silver-speckled leaves.
• Hoya obovata has big, round leaves with silver flecks.
• Hoya linearis has thin, fuzzy, hanging leaves and likes cooler, damper spots.
• Hoya australis is a fast grower and a good bloomer for beginners.