Hoya kerrii is a species of Hoya native to the south-east of Asia. A specimen was collected by Arthur Francis George Kerr in 1910 or 1911 in the Doi Suthep mountains west of Chiang Mai (Northern Thailand) at an altitude of 390 m above sea level. It was transplanted to Kew Gardens where it flowered in August 1911, and the species was first described by William Grant Craib from that plant and the wild collections in 1911 Its origin area is South China, Vietnam, Laos, Cambodia, Thailand and the Indonesian island of Java. (Source: Wikipedia)
Hoya kerrii is a climbing plant that can grow up to 4 meters high (around 13 feet). Stems have a diameter of 7 mm. The leaves are 6 cm wide, 5 mm thick. Adult plants show inflorescences of 5 cm diameter and up to 25 flowers. The flowers are reflexed and pubescent about 1.4 cm. The corolla is white and the corona is red. They produce copious amount of nectar that stain like the Hoya meliflua, that is why the colour changes from white to red to brown. They smell only faintly or not at all.
As the thick leaves are spade or heart-shaped, the plant is sometimes named "Lucky-heart" , or Hoya Heart or Wax Heart or Sweetheart plant. I am cheeky and see it as an inverted heart so I am calling it bum-shaped Hoya.
Hoya kerrii Guide
LIGHT
Hoya kerrii is best placed in full sun, which allows the beautiful leaves to develop nicely and to keep the plant compact. Shade and too many nutrients will result in thinner and deformed leaves as well as more twining growth form . But it will flower several times per year even in shade.
WATERING
As in any other hoyas with thick waxy leaves, water only when the soil has dried out and make sure the soil is never saturated with water as this will lead to rotting; so again drainage is important.
HUMIDITY
The thick leaves aren't bothered about humidity levels so you needn't be either.
FEEDING
Not a heavy feeder, at least twice a year.
TEMPERATURE
Like other tropical plants, it will grow well on the higher temperature. Growth will slow or stop if things get cool so you will need a range of between 18°C - 27°C / 65°F - 80°F for optimal growing temperatures.
GROWTH HABITS
It will not grow or do anything for at least half a year because it tends to grow roots first, then vines and leaves. I am borrowing this phrase from a respected NZ collector, Ms. Colleen Jessen, because I thought it is the right description for its growth habit – “1st year it sleeps, 2nd year it creeps and 3rd year it leaps. “
CULTIVARS
There are several different cultivars of Hoya kerrii with variation of leaf thickness and flower size.
1. Hoya kerrii green 2. Hoya kerrii variegata 3. Hoya kerrii albomarginata 4. Hoya kerrii splash