Commonly known as trailing houseplants, hoyas are happy to grow indoors in bright light or outdoors in warmer weather. With their flowing foliage and beautiful flowers, these plants are an excellent choice to add to your list of plant must-haves. Learn how to plant, grow, and care for hoyas.
About Hoyas
Hoyas are a genus of evergreen perennial plants native to tropical and subtropical areas, and over 500 species have been identified. They are mostly creeping or vining, and many species love something to climb. In nature, many are epiphytic, meaning they grow on other plants and have no attachment to the soil.
In temperate areas in North America, many species are popular houseplants with attractive leaves and beautiful, often scented flowers. The plants grow well indoors and prefer bright light. They will tolerate fairly low light levels but may not flower.
Creeping types of hoyas look lovely in a hanging basket or allow them to spill over their pot and trail down off the shelf. Some hoyas like to climb, so plan accordingly when selecting a variety.
Hoyas have simple, oppositely arranged leaves, but with a genus composed of many members, the variation in leaf shape is huge. In fact, many people who refer to themselves as ‘hoya heads’ collect dozens or hundreds of species just for this fact–they have a never-ending selection of foliage shapes and textures.
Hoya carnosa, also known as porcelain flower. Credit: puha dorin
Hoyas do flower and are generally shaped like five-pointed stars. Some, like the Hoya lacunosa, have fragrant flowers! The flowers are frequently born in clusters, forming a ball or sphere. Many individual flowers are small, but some species sport blooms up to three inches in diameter.
With such a large genus, the cold hardiness of hoyas varies. While they are warm-weather plants, some can tolerate a bit of cold. Generally, hoyas can be grown outside in USDA zone 9 and warmer. Check the tag on the specific plant you purchased, as some varieties are less hardy than others.
When growing hoyas as houseplants, you can plant them in the same manner as other tropical houseplants, paying special attention to drainage. Outdoors, hoyas need a well-drained spot with gentle light.
When to Plant Hoyas
As houseplants, hoyas can be planted whenever you bring them home. Don’t feel you have to leave them in the tiny pot they came in. If you are going to plant them outside, it’s best to do so in spring to early summer but again, they can be planted at other times with care. Like other houseplants, they are less active in winter, so wait for spring to repot them when they need a bigger home.
How to Plant Hoyas
Hoyas can be purchased as small plants, commonly in 4-6 inch pots, online or at a garden center. Larger hoyas are also available in ready-for-display mode, at higher cost. If you purchase a very young plant, you may need to let it grow a bit before planting it outdoors.
To plant your hoya in a container:
Choose a shallow pot with excellent drainage. Although they are tropical plants, soggy soil can still lead to root rot. Use soil designed for succulents, or mix potting soil with perlite to ensure excellent drainage.
Snip circling or girdling roots and gently loosen the root ball if it is pot-bound.
Replant your hoya at the same height concerning the soil as before.
Press the new soil down lightly but firmly around the plant–don’t compact it, but you want to eliminate any air pockets.
Growing
Hoyas are known for their ease of care. As long as they have good drainage and regular watering, they’ll be pretty happy. Hoyas don’t mind getting a bit crowded in their pot. When repotting, choose a new container that is only an inch or two larger than the old one and loosen the roots a bit.
Hoyas like the filtered sunlight found under a forest canopy. If grown outside, give them a spot with gentle morning sun and midday through afternoon shade or under a canopy where they’ll receive only brief periods of sunlight. Indoors, give them a spot near a window but out of direct sunlight.
Hoyas will benefit from a monthly application of general houseplant fertilizer, following the package directions. Diluting the fertilizer in water works well. If grown outdoors in the ground, provide a balanced product 2-3 times during the summer. Prune hoyas for shape as needed.
Propagating your Hoya
Hoyas are easy to propagate. Follow these steps:
Select a piece of stem with two nodes.
Remove any leaves on the lower portion of the stem.
Fill a clear-walled jar or vase with water and place the cutting inside. More than one cutting can be rooted in the same container, but they may be difficult to separate later.
Submerge the node. If your tap water is heavily treated by your municipality, use bottled water.
Place the jar in a brightly lit spot out of direct sunlight.
Change the water twice per week to keep it fresh.
Your cuttings should start to root in a few weeks. Once the baby roots are about an inch or two long, transplant them to a moist potting mix. Two parts coir to one part perlite is an ideal starter mix to train them to grow out of water.
Types
Hoyas commonly sold in nurseries as houseplants include:
Hoya Carnosa cultivars such as ‘Krimson Princess,’ a two-toned plant with green leaf edges and white centers. New foliage often displays pink and changes to green in maturity.
Hoya pubicalyx (often mislabelled as H. carnosa or H. purpurea-fusca)
Hoya kentiana leaves look like a bunch of pea or bean pods hanging off the vine.
H. kerrii, also referred to as Hoya hearts because the thick leaves are heart-shaped,
Hoya lacunosa is a compact, green foliage plant perfect for hanging baskets. It’s a favorite for the cinnamon-scented flowers and willingness to bloom. Many varieties are available.
Hoya linearis is a unique trailing hoya with short, cylindrical leaves. It’s perfect for a small green vertical display and can create a curtain of foliage.
H. pubicalyx ‘Pink Silver’ Credit: Vince Adam
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Wit and Wisdom
Hoyas are native to the warm and humid areas of southwest Asia, including the Philippines, Vietnam, India, and Thailand. Mimic the warmth and humidity for happy hoyas with lush foliage and beautiful blooms.
Older hoya plants can develop woody trunks, adding to their tropical mystique.
If you sometimes forget to water your houseplants and then panic and go darting from room to room fearing dead plants, hoyas are perfect for you!
Pests/Diseases
As houseplants, hoyas are susceptible to all the common houseplant problems common to other indoor plants. Since there is no worry indoors for pollinators, Neem oil or insecticidal soap works well. Use care, as some plants are susceptible to burns from Neem oil.
Andy Wilcox is a flower farmer and master gardener with a passion for soil health, small producers, forestry, and horticulture. Read More from Andy Wilcox