How to Grow, Care and Propagate Wax Plant (Hoya carnosa) Indoors

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Wax Plant (Hoya carnosa) blossoms in bright light with some direct sunlight, average warmth, moderate humidity and moderately moist, rich, well-drained, hoya potting soil coupled with monthly feeding in the growing season.

Hoya carnosa also called Porcelainflower is one of the popular flowering plants which bears fleshy leaves and clusters of waxy, fragrant, star-shaped flowers.

The twining stems can reach 15 feet or more making it ideal for a hanging basket or a trellis. The leaves are heart-shaped and fleshy with a glossy surface.

Care for Hoya carnosa is easy if the don'ts are observed. Some of these are don't disturb the plant once the buds appear as change in light intensity may cause them to drop.

Don't remove the dead flowers as new flowerbuds will form in the spurs. Don't repot until it is unavoidable as being root-bound encourages flowering. It benefits from loose potting medium that allows some air to get to the roots.

Botanical name: Hoya carnosa
Family: Apocynaceae
Subfamily: Asclepiadoideae
Common names: Wax Plant, Porcelainflower

Origin

Hoya carnosa is native to Eastern Asia and Australia where it grows as an epiphyte, climbing on trees in the humid subtropical forests.

Air Cleaning

Studies carried out at the University of Georgia have shown that Hoya carnosa is good at getting rid of pollutants from indoor air.

Varieties

Many cultivars of Hoya carnosa have been developed which vary in foliage form or flower color. Some of these cultivars include;

Hoya carnosa 'Compacta' or Hoya carnosa 'Krinkle Kurl commonly called Hindu Rope which bears curly twisted leaves on the stems which hang downwards.

Hindu Rope Hoya has a variegated cultivar, ‘Mauna Loa’, whose green leaves are cream to pinkish in the center.

Hoya carnosa ‘Krinkle 8’ has dimpled leaves. The '8' is in reference to the number of dimples in the leaf. It is similar to Hoya carnosa ‘Chelsea’ which has 6 dimples and Hoya carnosa ‘Krinkle 8 Variegata’ whose leaves are cream-edged.

Hoya carnosa ‘Argentea Picta’ which bears rounded, silvery-green leaves, with cream edges.

Hoya carnosa ‘Argentea Princess’ which is similar to Hoya carnosa ‘Argentea Picta’ but the cream variegation is on the inside of the leaves.

Hoya carnosa 'Krimson Queen' also called Hoya carnosa 'Tricolor' whose leaves start off with pinkish variegation on the edges which turns cream as they mature.

Hoya carnosa 'Krimson Princess' also called Hoya carnosa 'Rubra' with leaves which are pinkish to cream in the center and green along the edges.

Hoya carnosa ‘Freckles’ also called Hoya carnosa ‘Freckles Splash’ which has fine silver markings on the dark-green leaves.

Toxicity

Hoya carnosa produces a milky white sap which contains latex. The latex is considered to be toxic to humans and pets. Always wear gloves when handling the plant and keep it from the reach of children and pets.

Where to Buy

If you are looking to add Hoya carnosa to your collection, they are available online on Amazon (Link to Amazon) and on Etsy (Link to Etsy).

Hoya carnosa Care Indoors

Wax Plant (Hoya carnosa) thrives in bright light with 4-6 hours of direct sunlight, average warmth of 16-26⁰C, moderate humidity of 50-55% and moderately moist, rich, well-drained, hoya potting soil coupled with monthly feeding during the growing season.

Hoya carnosa requires pruning to keep it neat, minimize pests and encourage a bushy compact growth. Repotting is needed only when it becomes extremely pot-bound as it blooms best when root-bound. Keep reading for more on these growing conditions and how to achieve them.

Light Requirements

Wax Plant grows best in bright light with 4-6 hours of morning or late afternoon direct sunshine. Do not expose it to hot direct sunshine as it can scorch the leaves.

Hoya carnosa can adapt to lower light levels but it will become leggy and will not bloom if the light is not enough.

Where the natural lighting is not adequate, consider installing a grow light to supplement it. Check out these full spectrum grow lights on Amazon.

Rotate the pot regularly to make sure that the plant receives light on all sides for an even growth to prevent leggy growth.

Watering

Water Wax Plant thoroughly during the growing season while allowing the top 2-3 inches of soil to dry out between waterings to keep the soil moderately moist.

Lessen watering during the cold season as growth is minimal at this time to maintain the soil slightly moist but do not let the soil dry out completely.

Ensure that the pot has a drainage hole to prevent the soil from getting soggy as it can result in root-rot and eventual loss of the plant.

Temperature and Humidity

Hoya carnosa thrives in average warmth of 16-26⁰C during the growing season. Keep it away from cold and hot drafts to prevent sudden changes in temperature as they can cause leaf and flowerbud drop.

Wax Plant has no need for extra humidity; average room humidity of 50-55% is ideal for this plant. Do not mist the plant to avoid wetting the flowers as it can lead to rotting. Also, do not disturb a plant that is in flower as it can shorten the flowering period.

Regularly clean the leaves by damp wiping with a soft cloth to get rid of dust as well as discourage pest and disease infestations. Ensure that there is good air circulation to prevent fungal diseases.

Fertilizer

Feed Wax Plant with a phosphorous-rich, water-soluble fertilizer every 4 weeks during the growing season to promote flowering. Do not feed in the cold season as growth is minimal at this time.

Potting Mix

The best soil for Hoya carnosa should be rich in organic matter and free-draining to prevent it from getting soggy while providing the required nutrients. Buy quality Hoya potting mix from Amazon.

Repotting

Repot Wax Plant at the beginning of the growing season only when the plant is extremely pot-bound as it blooms best when slightly root-bound.

Do not repot a Porcelainflower that is in the flowerbud formation stage as it can drop the buds. Use a pot 1 size larger and one that has a drainage hole to prevent the soil from getting soggy as it can lead to root-rot. Take a look at these ceramic pots with drainage holes on Amazon.

Pruning

Pruning Wax Plant is easy. Remove the dead leaves to maintain the plant neat and discourage pests and diseases. Don't remove the dead flower stalks as more flowers will form from the spurs. After flowering, cutback the stems to rejuvenate growth and to prevent the plant from becoming unruly.

Propagation

Wax Plant (Hoya carnosa) can be propagated at the beginning of the growing season from stem cuttings or by air layering.

How to propagate Wax Plant from stem cuttings

Take 4-5 inches stem cuttings from a healthy Wax Plant plant. Ensure each cutting bears at least 1 set of leaves.

Insert the stem cuttings in moist free-draining soil and place the set up in a warm, well-lit spot away from direct sunlight.

Maintain the soil moist through out until the new Porcelain Flower plants are well established after which you can begin routine care.

How to propagate Wax Plant by air layering

Make a cut (notch) on the stem of a healthy Wax Plant. Coat the notch with a rooting hormone and surround the area with damp moss.

Cover the notched area with a polythene film or clear plastic wrap and maintain moist until roots develop.

After the roots have formed sever the stem just below the covered part, remove the polythene and carefully pot the rooted cutting.

Place in a warm, well-lit place and maintain the soil moist until the new Wax Plant is well established after which routine care can begin.

Hoya carnosa Problems Indoors

Wax Plant (Hoya carnosa) problems include flowerbud drop, lack of blooms, brown leaves, shriveled leaves, pests and diseases among others.