Growing exotic plants can be easy if you know the requirements of the plant species. Many exotics originate from tropical areas that have an extremely different climate pattern from the home or greenhouse environment. While not all aspects of a plant's native habitat can be met perfectly, there are some critical elements that need to be considered that are basic to all plants.
Most plants can be broken down into three light groups, low medium and high, and from there whether they like full sun, partial sun or shade. Some exotic plants come from tropical areas where the plants are exposed to very bright reflected light but do not actually receive any direct sun. Some shade-loving plants live deep in the jungle where very little light ever penetrates the canopy reaching the forest floor. When placing a plant consider that southern exposure of a house receives the brightest light, east and west medium, and north low light.
Temperature can be critical to an exotic plant. Those from warm climates often can not withstand freezing temperatures or they live in high cloud forests that never get above 75 degrees and never drop below 45 degrees. Many other plants need a freeze or a seasonal temperature drop to initiate dormancy or flowering. Most tropical plants will do well in normal home temperatures, but some will not flower without a temperature variation similar to their native habitat.
Soil types differ dramatically depending on the type of plant and where it is native to. Exotics like some orchids, ferns and bromeliads do not require any soil at all. Plants that root in the ground are called terrestrial. Those that root directly onto trees are called epiphytic, and those rooted on rocks are called lithophytic. The typical tropical houseplant likes a rich, well-draining soil that retains some moisture but does not stay wet.
For many tropical exotics humidity can be critical, especially for epiphytes that are grown mounted on wood where roots will wither away if the air is too dry. If the humidity is too high or there is not enough air circulation, mold and bacterial infection can develop. Exotics originating from desert climates typically are not harmed by too low humidity. Humidity can be increased by setting the plant on a shallow tray of pebbles filled with water just up to but not touching the bottom of the pot. Some high-humidity-loving plants might need a terrarium.
Soil type and species of plant dictate watering needs. Typical tropical house plants like to remain moist, but not sopping wet, and some need to dry slightly between waterings. Desert plants like to dry completely between waterings. For plants that have a dormancy period, watering should be reduced while the foliage dies off and remain dry or sparingly watered until the growing season. Many exotics are sensitive to salt deposits in the soil and require regular flushing with RO (reverse osmosis) or distilled water.