Orchid pollination and seed germination
As you can see from the picture below, we recently went orchid-watching in the nearby forest. We found Dendrobium aphyllum and other species in blossom. It looks almost unreal to see these beautiful flowers sprouting out from a naked dormant tree (epiphytic orchids grows on trees without harming them). D. aphyllum just burst its flowering buds also here at Dokmai Garden. That we rarely see these orchids in the forests made me think of how vulnerable natural orchids are, and that we should never buy any orchids from road side dealers or vegetable markets, only from CITES certified dealers.
An interesting way of learning more about your garden orchids, is to stimulate their fruit production. The orchid fruit is a dry capsule, full of seeds that are so small they resemble spores or dust. Since the orchid may demand special pollinating insects which may not occur in your garden, you may have to transfer the pollen to the stigma by hand, to initiate fruit formation. Orchid pollen is usually hidden under a lid in the hornlike structure (the column) above the lip. Use a magnifying glass and a needle to search for the bright yellow pollen packages (pollinia). You can practice on a garden orchid which you detach and totally rip, just so you learn its anatomy. Then gently repeat the pollination on a flower you wish to pollinate. The pollinia should be transferred to the female part, the stigma, which in the case of a Dendrobium may look like a pit on the column. Then observe the flower for a few days to see if you were succesful. A fertilized flower usually drops its petals soon, and fruit formation starts. Once the fruit gets brown and dry, it will open up. According to my experienced orchid friend Dr Bronsema, you increase your chances of seed germination, if you use an artificial growth medium, such as “Knudson C”. That can be bought here in Chiang Mai at the intersection between road 1001 and the expressway.
The vision is that gardeners can buy native orchid species from certified dealers, and then produce little seedlings which are genetically different from the mother plant, and then further enhance the beauty of the garden as well as putting back orchids in an original forest! However, the latter step demands very good knowledge about each species’ ecology, because on the wrong spot the orchid will die. The best way to learn where they thrive, is to see how they grow in the national parks. Note the tree species, note the North-South directions, note the altitude and note how high in the tree the orchid grows. Also, always collaborate with the national park manager, as they need to know about any change. Scientists could make terrible mistakes if they start monitoring outplanted orchids instead of naturally established orchids.
If the pollination sounds difficult, we offer anybody with a Dokmai Garden ticket a supervised lesson using a dissecting microscope. This offer is only made as long as we have plenty of orchids to play with. If you wish to be sure to have a private supervised pollination lecture, then bring your own orchid. Vanda is easy to handle and displays the structures nicely.