Recently this little problem has started again. On my cape sundews that are overall doing good (flowering prolifically, nice coloration etc...) they occasionally send up leaves that fold up or twist on themselves. Instead of having to "unhinge" one fold in the leaf at the transition point between petiole and lamina, the lamina is also folded once.
Ive been having this problem for a little while now, but I havent been able to pinpoint the cause. Im pretty sure its not pests, I've gone through soil and plant with a magnifying glass to check for anything out of the ordinary.
Other symptoms (maybe) include the flowers not opening completely.
Watering: refill trays, when they're almost dry, to .5 inches or less.
Pot size: 4.5 inches wide 4 inches deep.
Soil: peat sand 1:1
Water:distilled, rain, or RO only.
Feeding: once every month, sometimes more if they catch an occasional moth or other bug.
Lighting:48'' t8 bulbs (mix of warm/cool) about 3 inches from leaf tips. I dont think the lights are burning the leaves like they did before, this time even the beginning leaves are growing twisted.
Humidity:low usually. Relative humidity in my area ~9%
Probably a little higher than that over the trays, but definitely not above 20%.
How the deformed leaves look like when they are first forming
How they look like after they're done unfurling.