Question
I have a Pinguicula, allegedly moranensis, that I bought from another company a few years ago.  It's growing, staying sticky, and even produces offsets.  But neither the original nor the offsets are blooming.  They produce buds on a fairly regular basis, but the whole time I've had them only one or two have ever opened.  The rest have all shrivelled up and died, starting with the stem.  It's growing in 50% peat, 50% perlite.  I received it potted in sphagnum moss, but it appeared to have been kept waterlogged and was rotting, so I put it in my regular mix.  I water it regularly but try not to let excess water remain in the tray.  I keep it in an east window most of the time, but that room gets very hot in the summer so I move it to a cooler room where the only thing available is a south window.  The windows are double-paned and have screens, so it's not scorchingly bright.

Answer
Hi Jim,

There are three common reasons why buds fail to open.  The first is low light.  It takes energy for the plant to produce flowers.  If the light levels are too low, the plant will sometimes halt a bud's growth right before it's time to open up the flower.

The same is also true for humidity.  If the air is too dry, the buds will lose a lot of moisture through the flower stalk and bud.  This will cause the bud to eventually shrivel up prematurely.

The third reason is keeping the soil too moist.  Based on your description (shriveled up and died, starting with the stem), this is probably the most likely cause.  Pinguicula soil should be damp, but never waterlogged.  Unfortunately, the mix you used (1 part peat moss and 1 part perlite) is too wet for this species.  While it is possible to use this mix, you'll need to give it water only when the top of the soil feels dry.

If possible, transplant your butterwort into a courser mix.  Use 1 part peat moss and 2 parts perlite.  You can keep your plant in standing water, but no higher than 1/4 inch of water.  Add more water only when the saucer is dry for a day or two.

Otherwise, you can keep it in the same soil you have it in right now.  Instead of keeping it in standing water, set the pot in standing water, about 3/4 of the way up the pot.  Let it sit for 5 minutes to saturate the soil, and then drain the pot completely.  Set the plant back in the windowsill when the water is drained out.  Water again using this method only when the soil feels dry on top.

Good growing!
Jacob Farin