August 2012

This Sulawesian species was collected in 1994 between Tentena and Kolonodale. It is very similar to H. paulshirleyi GPS 8845 and to GPS 8865 and GPS 8870, but the flowers are much lighter. It was growing high up in a fairly large tree which made it very difficult to collect. The only way we could get at it, was to try and knock off a few pieces with a branch. It was one of the first plants we collected that flowered in cultivation and it flowers freely and at a young age. Without flowers, this species and GPS 8845 are impossible to tell apart.
It is a very easy plant to propagate by cuttings, unlike the GPS 8845, and will root in about 6-8 weeks. The plant can take a reasonable amount of sun and the leaves will turn reddish if kept in the sun giving a nice effect; they will stay green if kept in the shade. It is a sort that requires warmth to do well, 20°C and over. It can also take a lot of dryness before it dies. So far, I have not seen any seedpods on this species, despite the fact that there are lots of moths in the greenhouse that should have done the trick.


Hoya sp. Sulawesi GPS 8860

Hoya sp. Sulawesi GPS 8860


This caudiciform species comes from China and is very easy to grow. It can be grown outside in the garden in the summer, or just as easily in a pot. It can take a little bit of frost, especially if the soil is very sandy and well-drained. If you do not have this sort of soil, it is advisable to take them out before the winter and treat them as you would Dahlia tubers. The tubers are potted up in spring and can be either buried completely or half above ground so you can still see the tuber (see photo below). The plant prefers cool conditions (10-18°C); if the temperatures are too high (for instance, if you keep them in a greenhouse where the day temperatures get above 25°C), the flowers can become misformed.
The flowering period is from May to August and the colour of the flowers can be pink or white; the variety show in the picture is ‘Snowtop’. This genus does also have a yellow-flowered species, Incarvillea lutea, but that is a very rare sort.
Seed collected one year can be sown the following spring. The plant will form a tuber that first year and will flower the following year, so two years after collecting the seed. It is a relatively pest-free plant, but watch out for greenfly.

Incarvillea delavayii Snowtop tuber

Incarvillea delavayii Snowtop flower