Dear aroid horticulturists,
Here I am again being curious.
What is happening when an indoor plant is moved outside and experiences
massive blanching? This seems pretty universal for plants, not just for
aroids. If the weather is clement, new leaves will eventually appear
that are hearty enough to be fully green and lush without any
protection. Sometimes those leaves are smaller or more intensely green
than the indoor versions. But it means the plant is capable of receiving
a full dose of weather and sunlight. It is as though leaves with
different endurance characteristics are produced to match a given
climate situation. It does not even help if the transition is made very
I have heard before that this involves a cuticle layer that either
inhibits desiccation or not depending on whether or not it is present.
But the blanching I refer to does not seem to involve desiccation -
except if it is so severe that the leaf dies and the desiccation is
associated with necrosis. Plants kept moist and in humid conditions will
The reverse is also true - sort of. Plants with "outside" leaves are
stalled when brought indoors. Most of the time the outside leaves stay,
but when new ones come on they are now of the weaker "indoor" variety.
Soon enough the outside leaves fall off, apparently ill-equipped to
function in the new climate.
It is not always the case that outdoor leaves die when brought inside.
But it is almost always the case for the reverse.
Do we have different chlorophyll types, or internal shading or
I know somebody knows the answers.
Thanks for indulging me.
Aroid-l mailing list