Hoya carnosa 'Tricolor'

Background and history of Hoya carnosa 'Tricolor'

B. L. Cobia, Inc. developed ‘Tricolor’ through a series of selections descended from Hoya carnosa ‘Variegata’. It arose as a sport on an unnamed plant in that line. United States Plant Patent 2,950 described it in 1969; Patent 3,105 established the cultivar name in 1972. ‘Tri-Color’ is a later synonym. KRIMSON QUEEN was its trade designation; that trademark expired in 2002.

How to care for Hoya carnosa 'Tricolor'

Let ‘Tricolor’ climb a hoop or trail from its pot. Place it in bright indirect light with protection from hot sun, at about 18–27°C and 40–60% relative humidity. Keep temperatures above about 13°C and allow gentle airflow around the leaves.

Water when the chunky mix is nearly dry throughout and the pot feels light. Check moisture deeper in the mix where necessary, soak the whole root ball and drain fully. The mix dries more slowly as growth slows or light decreases.

Give a light balanced orchid feed about every two weeks during new growth, following the label. Pause when growth stops and flush with plain water every few months. Repot one size larger when roots need space. Replace deteriorated mix in the same-sized pot if the roots still fit. Check the new compost’s label for added fertiliser and advice on feeding.

For propagation, wear gloves because the sap can irritate skin, and use a clean blade to take a one- or two-node stem cutting. Remove the lower leaves and root that node in lightly moist mix, with the remaining leaves above the mix. Keep warm in indirect light and humid air, ventilating any cover. Once rooted, transfer the cutting to a small pot with drainage holes.

Troubleshooting Hoya carnosa 'Tricolor'

• Wilting with persistently wet mix: Persistent wetness can damage roots. Drain trapped water and inspect roots if decline continues. If you find a small amount of root rot, use a clean, disinfected tool to cut the soft roots back to firm, healthy tissue. Throw away the rotten roots and old mix. Repot in fresh, airy mix, using a clean pot just large enough for the roots that remain. The pot must have drainage holes. If decay is widespread, save only healthy stem cuttings. Discard the plant if no healthy stems remain, and disinfect your tools afterwards.
• New bleached or crisp patches facing the light: Firm young leaves can be pink or red as part of their normal colouring. Hot sun or a sudden increase in light can scorch leaves. Move the plant into bright, filtered light. If you later move it to a brighter position, introduce the stronger light gradually. Existing dry patches will not recover; retain healthy foliage.
• New speckling (stippling) with fine webbing: Inspect damaged leaf undersides with magnification; tapping a leaf over white paper can help locate mites. Confirm spider mites before treatment. Isolate the plant, gently rinse both leaf surfaces and let water drain. Recheck every few days and repeat rinsing while live mites remain.
• Cottony insects on stems and leaf undersides: Confirm mealybugs beneath the wax and isolate the plant. Remove visible insects with a damp swab or tweezers. Inspect sheltered leaf joints, stems, the pot and any support weekly, removing any mealybugs you find until none remain. If mealybugs persist, use a product approved for home use against mealybugs on indoor ornamental plants in your country. Follow the label for how much to use, where to apply it, when to repeat treatment and all safety precautions.

Hoya carnosa ‘Tricolor’ is non-toxic to people and pets

• This plant is non-toxic to people, cats and dogs.
• Chewing a large amount can still cause an upset stomach.
• If a large amount is eaten and symptoms continue, contact a veterinarian or medical professional.

How the name Hoya carnosa came about

Hoya honours the English gardener Thomas Hoy. The Latin epithet carnosa means fleshy and refers to the thick leaves.

Robert Brown established the genus Hoya in 1810 in Prodromus Florae Novae Hollandiae, page 459.

Carl Linnaeus the Younger first described it as Asclepias carnosa in 1782 in Supplementum Plantarum, page 170. Robert Brown later placed it in Hoya as Hoya carnosa in 1810 in Asclepiadeae, page 16.