O : ( Orchis, Ophrys, Barlia, Serapias )
Plants are growing in dry calcareous meadows and need much sun. During vegetative period they like slightly moist conditions but with exellent drainage. In rest period they need dry condition to prevent rot. Compost : 3 parts pumice gravel, 0,5 parts gritty clay, 0,5 parts perlite, 1 part cocosfibres, 1 part limestone.

Om : ( Orchis militaris )
As O but plants are hardy in center Europe and don’t need a strict dry rest period. Compost as O. A outdoor plant.

Pe : ( Aminostigma, Poenorchis, Hemipilia )
Asian generas related to Orchis, growing in meadows or between rocks. Plants maybe hardy but winter in natural      habitat is much drier than in Europe. Best way is to hold tubers dry and cool in special room during wintertime. Compost and cultivation as O but maybe without limestone.