Plant white nun's orchid outdoors only in regions that never receive freezing temperatures. The soil should be moist, well-draining and rich in compost or humus; in winter allow the soil to become slighter drier. Avoid getting the foliage wet when the orchid is watered if not done by natural rainfall.
Ensure that this ground-dwelling orchid receives very bright indirect light or partial dappled shade under the protective canopy of trees or tall shrubs.
Fertilize lightly and frequently from spring to fall when the orchid is actively growing. Liquid fertilizers may be used, but apply them at about 1/4 the strength as the label directions list. Do not fertilize during the drier winter period.
Transplant large clumps after the orchid flowers. Retain as much of the root mass when digging the clump out and replanting.
Plant white nun's orchid in a spacious container to allow ample room for its many roots. The potting soil should be peat-based, moist and well-draining.
Position the orchid in its container in a brightly lit window out of direct sunlight. Humidity should be high and can be increased easily in an average home environment by setting the container atop a saucer of small pebbles that are in water. The plant may also be misted.
Water the orchid to keep the soil moist but not soggy. In winter the plant should be allowed to become slightly drier before the next watering. Use warm, room temperature water, not cold. Do not allow water on the foliage.
Fertilize during the growing season, from spring to autumn, at every third watering, with an orchid fertilizer mixed at 1/4 the strength as listed on the box. Do not fertilize this orchid during the winter.
Consider repotting the orchid only after it becomes pot-bound, such as after two to three years. Retain as much of the rootball as possible when transplanting into a slightly larger container. Transplant after flowering, not during or when the flower spike is first emerging.