Students gave a zoom tour of the greenhouses today for our Sarawak orchid Society and this Stanhopea species was one of the highpoint with its wonderfully fragrant large flowers. Like all our Stanhopea species the flowers are produced on dramatic pendulous spikes that keep the flowers well clear of the leaves and bulbs. The flowers last for a few days but while they are out they are magnificent and once they reach a good size they produce several spikes that give flowers over several weeks.
Stanhopes graveolens is a Central American species. We have seen related species in Costa Rica growing in wet evergreen forest around 1000m. This gives something of a challenge in cultivation as the plants must be in baskets so that the downward growing flower spikes emerge safely but baskets easily dry out especially when hung up high in the roof. Our solution is to hand the plants relatively low down in the greenhouse – at around bench hight – so that they are well watered and then hang them up higher when they flower so that the flowers are at nose height.
The wonderful scents are to attract euglossine bees (as do Gongoras). The males collect the perfume oils from the flowers and then use them in their display to attract females.
We find that stanhopeas are straight forward to grow form seed in our lab, and we will be adding our first Stanhopea species to the online shop tomorrow, including mature seedlings and seedlings in-vitro, for those who want to give these spectacular summer flowering orchids a try.