Cleistocactus strausii
The cactus prefers free draining soils, strong sunlight, but not high temperatures — in fact it can withstand hard frosts down to -10 °C. In its natural habitat it receives plenty of water during the summer, but almost none over the winter. In cultivation, watering too much in winter often leads to root rot.
Cypripedium acaule
For artificial cultivation container culture is a must, and the growing medium must be naturally acidic. Additionally, all other soil additives must be devoid of any calcium that could buffer the pH to above 5. High quality peat moss or pine duff work well, and pH neutral perlite can be added to improve porosity. Due to the risk of calcium bicarbonate, tap water is unsuitable. Rainwater or distilled water mixed with of vinegar per gallon will assure that a reliably high acidity is maintained in the growing medium. Give bright dappled shade or morning sun. Sink pots in winter or store in a cold frame for insulation. Given these conditions "C. acaule" can thrive indefinitely, but will always require much more maintenance than other species/hybrids that can be grown in a wider pH range.