Q. What kind of flower is this?
I have had a flower bloom from an aquatic plant in my tank, which is attached to half a coconut shell. It’s beautiful — but what is it? I tried researching underwater flowers on Google but could not find a relevant picture. I have had this plant for 18 months, and it did something like this a year ago, but the flower was not as big. JOSHUA GRAVES, EMAIL
AThis is an Anubias species, almost certainly Anubias barteri, var. nana,a member of the Araceae group of plants, often called the Arum lilies. The Peace lilies (Spathiphyllum spp.) often kept as houseplants belong to the same group. All of them have this very distinctive single, scoop-shaped petal-like structure called a spathe that looks like a petal but isn’t; the many tiny flowers are on the stick-like structure on the inside that is called a spadix. This group of plants is remarkable for including some of the largest flowers known, the spathe and spadix of the Titan arum can measure up to 3m in height! Getting back to your Anubias, one of the things to realise about this plant is that it is really a marsh plant rather than a true aquatic, and this flower is meant to attract insects that will carry pollen from one flower to another. Under aquarium conditions the flower eventually rots, but it still puts on a good show! Quite what triggers flowering is unclear, possibly changes in day length or temperature, but really, this does seem something that happens with some specimens but not with others. I’ve had Anubias that bloom once most years, while others did nothing.
Because these are marsh plants, optimal conditions would probably be a paludariumtype set-up that allowed the plant to extend above the waterline across wet rocks or bogwood. But as I say, getting Anubias to flower on demand isn’t easily done, and you might have to content yourself with simply enjoying what is an occasional, but interesting, occurrence. NEALE MONKS