When I last grew them (many years ago) they were mainly formosana cv.s and I didn't come across this, but a few of my Pleiones (Rakata Locking Stumps, x barbarae & Tollima) are curling their leaves longitudinally. Growth seems vigorous enough (Rakata leaves to 22cms long) and pots are very well filled with roots, so I'm not unduly worried, but the leaf edges of these are rolled back so much that they are almost forming a tube. To a lesser extent this is also happening with aurita and limprichtii, but I sense that it is not going to get any worse with them.
There aren't any pests, which is a common cause of leaf curl in many plants and temps. are within the range of 25C falling back to about 15C at night, which I presume is acceptable. Compost is a mixture of medium grade orchid bark, coarse, washed perlite and chopped sphagnum moss (2:1:1) and currently feeding is by one third strength Chempak no2 (high nitro) every other week together with half strength Maxicrop Seaweed tonic every 3 weeks. Watering is carried out as necessary - usually every day due to the very free draining nature of the compost. Ironically, the least worrisome is P. forrestii, which was first off the mark this year and has a fine, almost aspidistra-like leaf, masses of root and is thickening well at the base. Are these warning signs requiring remedial action or am I getting a just bit paranoid?
TIA
