As you narrow your list of plants for a container, check the moisture, soil and light requirements of each one. Different plants are adapted to the diverse environments of our planet. Plants adapted to dry climates usually have thick, waxy, or hairy leaves to hold moisture. The roots of these plants often like to dry out between watering. Succulents like jade plant, Christmas cactus or hens and chicks are examples. Succulents suffer root rot and die if the soil stays too moist or is not allowed to dry somewhat between waterings. Plants native to moist areas need steady, even moisture. To combine plants that do not have similar needs, see double potting.
Often the plant label lists environmental requirements. Many books and websites can be searched with the specific name of a plant you are interested in. Scientific names usually yield better results than common names. If you do not know the scientific name, you can sometimes find it by looking for information on the common name first. When you find the scientific name, use it to determine the specific plant needs.
Balancing the watering with the pot size, type of container, soil types, and how large the plants are likely to grow in one season can be an art. It is fun and interesting, and unlike people, plants can be replaced, so do not be afraid to experiment. If plants fail, pull them out and replace them. Even people with a "green thumb" experience a plant dying from time to time. Just enjoy the aromatic and visual pleasures of plants and learn from your inevitable mistakes. If you are uncertain why an occasional plant dies, talk to other gardeners or contact your state's land grant university Extension Service for troubleshooting ideas.