Pleiones are easy to grow if the grower keeps to a few simple rules:
First, DO NOT WATER AFTER THE LEAVES HAVE FALLEN in autumn.
Secondly, do not keep in a warm place, most of them will stand up to 6 degrees of frost.
Keep in a shady dry place all winter, (a garage will do), as they need no light. Place a few mothballs in or around the pots, to keep slugs and mice away.
Repotting is best done in January, while the corms are dormant, but be careful not to break off the tiny buds, creeping up the side of the corm. Take off most roots to about an inch, gently pull off leaf residues, and clean up the corm. Wipe over with a mixture of 1 teaspoon light cooking oil, 1 teaspoon liquid soap, in 1 pint of water, shaken well, or rinse for a few minutes in a dish of insecticide to clear any insects. The main pest is a tiny false spider mite called Brevipalpus, which is not noticeable, but might just be present in the rooting area under the base of the corm. Do not put your hands into insecticide, as you can absorb it through the skin. Use waterproof gloves, or a spoon.
Pleiones are terrestrial, so they normally grow in leaf mould, but the places where they would be found in the wild have so much rain in the summer, that there is very little nutriment in the soil. If you wish to use an orchid mixture for repotting, it should be very free draining. The pot should hold a bottom layer of crocks or coconut fibre cubes, old coir matting or coarse bark. The second layer should contain moss, preferably from trees, and Perlite, a little peat, a larger quantity of fine or medium bark, and possibly some charcoal or chopped bracken. Mix these with a little water to keep the perlite dust down. A few sulphur pellets help to reduce fungus attacks, but this is a matter of choice.
Place the corms in the compost, about an inch apart, and leave most of the corm above the surface. I plant mine more deeply, because I find that shallow planting allows corms which are heavy with flowers to fall over, or are dragged out of the pot by nearby flowers. Set the repotted plants aside to dry out, the water should not stimulate growth, but will help to reduce shrivelling of the corms.
Only bring into a cool light place, and spray lightly, when the flower buds appear in February and are about to open. When the flowers are ready to open, spray with an insecticide like Provado to protect them from aphids, and they will give a beautiful display. If you take them into the warmth of the house, the flowers will die much sooner. They have a short flowering period of less than a month, and can be seen to advantage if left on a shelf in a porch, or un-heated conservatory. Remove dead flowers, and as they dry, and the stems as well. Slugs are not normally a problem, but mothballs deter them.
After flowering, watering can begin in earnest. The leaves enjoy a regular weekly feed of half strength nitrogen feed early in the year, changing to high potash feed after June. They enjoy being left in a shady place in the garden, in summer, where it is cool.
But they do not tolerate summer drought, so water with rainwater if available, or tap water if necessary, every other day. The leaf size depends on the variety of plant, but a good pleione will make leaves like an aspidistra, four or five inches wide and up to fifteen inches long.
In September or October the leaves go brown, and will fall off naturally. Keep watering until they have gone as most of the corm size is made up in late autumn. By mid November they should be in their winter home, and resting until spring. Pleiones do not need to be repotted every year, but certainly every second or third year.
This gives you plenty of time to enjoy a carefree Christmas, and unless due for repotting, you can forget them until early spring.
See also The Pleione Website created by Paul Cumbleton.