The other day Karin bought a Miltonia orchid to add to the ever-expanding collection of orchids she’s accumulating. It’s nowhere near as large as the collection she accumulated in our old place in the UK – part of it is pictured in this old post of mine – but it’s only a matter of time. This morning I showed her how to extract orchid pollen from the flower and her squeals of delight were something to hear!
As you can see in the image above, these orchids package their pollen into discrete structures that we term “pollinia” – two of them in this case, though the form and number of pollinia vary between different groups of orchids. The pollinia plus the sticky organ that attaches them to a pollinator is collectively termed a “pollinarium”. The only other plants that present their pollen in this way are my beloved asclepiads in the family Apocynaceae. The orchids and the asclepiads are only very distantly related to each other so this is a clear example of convergent evolution, where both plant groups have come up with the same solution to a problem. In this case, the problem is probably that bees collect a lot of pollen which has a reproductive cost for plants. Packaging the pollen in this way prevents bees from stealing it, amongst other advantages.
If you want to look at this yourself, you’ll find the pollinaria tucked under the front of the central “column” of the flower, which comprises the fused male and female reproductive parts. Just take a fine needle and gently stroke the underside of the column. In the image below, taken just after we extracted the pollinarium, you can see the “anther cap” which covered them lying just below the column.
It’s possible to learn a lot about botany from studying even common houseplants such as these!
Prof. Jeff Ollerton - ecological scientist and author 
Hi Jeff,
Thats really interesting. I was given an orchid 7 or 8 years ago but after the first year it didnt flower again. However, in August 2021 it began to bud and had 16 flowers. It flowered right through till the end of February 2022. In July 2022 it began budding again, it had 15 flowers and still has two flowers on it. Im not sure which the Pollinia is though is that it nestling at the back of the small cupped petal at the base of the flower?
I have another orchid from about 7 or 8 years ago but that has yet to flower again. I wonder if I could cross pollinate the two orchids if the second orchid ever flowers? Can I collect the pollen off this one now before the flowers drop off?
Thanks for your email posts I enjoy reading them.
Kind wishes Mary
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Hello Mary – I wasn’t able to see your photos, I don’t think that WordPress allows them on comments. Perhaps send me an email?
Jeff: Say the word and I will provide your readers with recent color reprints of photos showing how the pollinaria of tiny orchid flowers attached to the bodies fungus gnats. Some were taken by the great wildlife photographer, Rudie Kuiter. Your readers should become familiar with Rudie’s wonderful book, “Orchid Pollinators of Victoria” (fourth edition).
Thanks Peter.
Hello Jeff, I haven’t got your email address.
OK, if you send me a message via my Contact page I will email you back.