Re: P. Moranensis overwintering

From: Paul Temple (
Date: Sun Jan 24 1999 - 08:27:49 PST

Date: Sun, 24 Jan 1999 16:27:49 +0000
From: Paul Temple <>
Message-Id: <aabcdefg211$foo@default>
Subject: Re: P. Moranensis overwintering

Regarding the query on inducing dormancy in P. moranensis (from David I

>I also have a question about P. moranensis. I removed the pot from a tray
>of water maybe 1 to 2 months ago to try to induce winter dormancy. I have
>watered the pot occasionally, maybe once every 2 weeks for fear that the
>plants would dry out too much. They are still catching insects voraciously,
>and I'm concerned that I'm not giving them the winter dormancy they need.
>Any suggestions? Should I get tough!

OK. P. moranensis is a large group of plants all belonging to a single
species but showing a very wide range of variations. If you compared
two types that were most unalike (at extreme opposite ends of the
variations) then you could be forgiven for thinking them different
species, even botanists do this. However, there are intermediates
between all the types and no distinguishing features that do not show
variation so separation into any subspecies, varieties, forms or
otherwise are impossible. They are all one species (actually a
"complex", but still a single species).

Why have I bothered saying this? Because the variation is important.
There are many many different plants that are still part of the P.
moranensis complex. And they not only differ to different degrees in
how they look but also occur in widely differing locations spread over a
relatively large geographical area. So the plants differ and this
includes differences in how they grow and in what conditions they need.
(The first two P. moranensis plants that were widely cultivated were P.
moranensis types invalidly called P. caudata and P. mexicana. They are
entirely different in winter, one having a neat semi-dormant rosette
much smaller than its summer form and the other being a tangled mass of
leaves that differ from the summer form only because the plant divides
in winter and so there are more leaves fighting for space.)

So, some P. moranensis plants will not withstand extended exposure to
temperatures below 10 degrees celcius while other P. moranensis plants
are quite happy (if kept dry) at about 3 or 4 degrees celcius. It all
depends where the plant came from (or where its parents plant originally
came from). And this means that forcing or trying to force a P.
moranensis plant into dormancy can be fatal. If your plant is a
variation that comes from an area that is constantly warm rather than
cold and/or generally damp rather than seasonally dry, it is not likely
to be adapted for dormancy. Any attempt to encourage dormancy by
lowering temperatures or reducing water may rob the plant of its
requirements. Typically, pinguicul plants die by changing colour to a
sickly green that's impossible to describe but just about every Ping
grower knows when they see it. It just looks wrong. Unfortunately, in
almost all cases once you see this colour the plant is stressed beyond
any rescue attempts. It's dead and all you are watching are the final
death twitches!

What can you do? If you have a P. moranensis and don't know if it
requires dormancy, do as follows. Keep the plant slightly drier than
usual but not dry. Drop temperatures to about a 10 degree celcius level
ideally all day and night but certainly at night. Reduce lighting to be
no more than 8 hours a day, a little less if possible (7 or 7.5). Then
watch your plant. If it is able to be dormant, the leaves will change
and become more of a well ordered rosette, often of rather small
succulent (fat) leaves. The plant may even form a rosette that
withdraws underground but certainly most will hug the ground. The
leaves will also be dry to the touch. Such plants can be kept much
drier until the leaves suddenly start to grow, which you will see
starting at the rosette centre as new leaves obviously grow outward and
are clearly going to be larger than the rosette from the moment you
first see them.

If a plant retains sticky leaves and the leaves do not change in shape
or size, the plant is unlikely to require dormancy and may be killed by
attempts to induce it. So don't.

Hope this helps.



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