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Carnivorous Plants/Cottony growth on dewthreads


I just noticed this morning that some of my temperate dewthreads have a white cottony growth on the crowns of the plants. It is occurring on about half the plants right now and seems to be happening on all varieties.

My plants are growing outdoors in pools with full sun all day.

What is the growth and is it necessary to treat it? If so, what do I do?

As usual, thank you for your time.

Hi Bill,

What you're probably seeing is two things.  The first is that the center of plants like D. filiformis do have something of a hairy crown which does get more pronounced in the later summer.  Also, with the very warm temperatures we've been having, the plants are evaporating/transpirating large quantities of water.  Any minerals that are present either in the water or soil start to concentrate with so much water evaporating upward with tray watering.  The patches are little mineral deposits, and we often see it late summer.  When we start getting more rain again the situation reverses itself, but in the meantime, do more top-watering of your plants.  Having the water flush downward will reverse this.

Good Growing!

Jeff Dallas
Sarracenia Northwest

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