Another Insectivorous Plant

Flower of Butterwort, Pinguicula grandiflora, on my balcony in Hayes.  12 May 2013.

I have had no luck with Butterworts in the past.  Twice I have bought one and watched it slowly die.  But nevertheless, I tried again.

In January 2012 I bought a few small hibernacula of Pinguicula grandiflora.  These are the form the plant takes when it hibernates in winter, like little green buds.  It makes a bunch of little offshoots during the year, and these are what I bought, in their winter form.

They grew, and then they disappeared, only halfway through the year.  Well, I had seen some Sundew species do something like that, so I thought they might still be viable.  I put them out on my balcony and kept them wet.  And waited.  Squirrels dug them up, and some of them disappeared completely.  I was not too hopeful, but when I looked under the surface this spring I found lots of little hibernacula.  This time I just left them outside, though I put a few into different pots, some of them indoors.

Butterwort, Pinguicula grandiflora, on my balcony in Hayes.  12 May 2013.

The squirrels dug them up again, and I pushed them under again.

Now they have all come up, and the ones that are outside are all flowering!  So the answer to cultivating these is: leave them outside, keep them wet, keep the squirrels off them, but otherwise ignore them. 

Butterwort, Pinguicula grandiflora, on my balcony in Hayes.  Detail of leaf with trapped insect.  12 May 2013.

This is how they eat insects.  They are not spectacular like Venus Flytraps or Sundews.  At most, the leaf edges can curl up a little.  But a close look  at the leaves shows that they are covered with sticky-tipped hairs, smaller than a Sundew's but the same kind of thing.  When an insect gets stuck, glands in the leaves exude digestive juices, and the result is absorbed into the plant.

Wikipedia says the flower stems are long so that pollinators are kept well away from the leaves and don't get eaten, but I notice that the flower stems of mine are also covered with sticky hairs, so I am not convinced.