I've had mine flower once or twice, but not since...
I found this on "thekrib" website. Maybe it would be of interest.
"Flowering Anubias
by uweb-at-hpbidrd1.bbn.hp.com (Uwe Behle)
Date: Tue, 25 Jan 1994
Nicholas Plummer (nicholas.plummer-at-um.cc.umich.edu) wrote:
: Over the last couple of weeks, one of my _Anubias nana_ appears to have
: been trying to flower. It has sent up a short spike from the rhizome
: between two old leaves. The end of the spike has a single bud. The bud has
: not yet opened, but it looks like it will turn into something similar to
: the flower (is "spathe" the technical term?) of a peace lily
: (Spathiphyllum).
: Is it common for Anubias plants to flower while growing submersed? I was
: under the impression that since Anubias are typically only submersed during
: floods, they only flowered when grown emersed. I think this is what the
: Rataj and Horeman plant book said. I assume this is a sign that the plant
: is happy, but I guess it could be the last gasp of a dying plant. I know
: that abused orchids will sometimes flower one last time before giving up
: the ghost.
:
: Nick
This seems to happen a lot with the A. nana and A. barteri. Unfortunately
the flowers rot after a while and you have to remove them. The flowers
keep coming back. I had plants with two flower stems on them, one from each
end of the rhizome.
If you want to grow seeds you need to make sure that the humidity in the air
part of the tank is 100% and that the flower can reach above the surface.
Also it helps to have two or more A nana; the flowers are protected against
self fertilization by the spathe.
By the way, the A. nana grows mainly submersed in the natural habitat; as
a matter of fact it grows much better under water than emersed.
--
Uwe
NAME Uwe Behle, HP Boeblingen Instruments Division
EMAIL uweb-at-hpbbn.bbn.hp.com (internet), df3du-at-db0sao.ampr.org (packet radio)"
And this found on the Tropica site:
"Anubias barteri var. nana is a small, attractive plant which thrives in all conditions. It grows slowly, and the leaves survive for several years, giving slow-growing algae the chance to become established. The best result is achieved by planting on a stone or tree root. Fishing line can be used to attach the plant until it gains a hold. If planted on the bottom the rhizome must not be covered because it tends to rot. It flowers frequently under water. It is not eaten by herbivorous fish."
Hope this helps.
alicem