There is a very large variety of house cacti available for potting and growing indoors. Each has a different set of attributes that can make it more or less desirable depending on the environment in which it will be growing. Some cacti are very small and grow slowly, while others are more aggressive and can grow taller than the ceiling in most homes. There are cacti that love water, and others that love to be neglected in the sun. The main thing to look at when choosing house cacti is the requirements of the plant in relation to the amount of care that can be provided.
Many people choose to grow house cacti because they are generally very low maintenance. They do not need a great amount of watering and can go days without any attention at all. One easy rule to remember when looking at different cacti is that varieties with flat body segments require more water than types that grow in the shape of a sphere or cylinder.
Temperature is an important factor for most house cacti. They are most comfortable at room temperature or warmer but can easily die if the temperature drops too low. In the winter, a cold draft can kill the plant even if the indoor temperature is adequate. Larger cacti tend to be more resistant to the cold than the smaller potted ones.
Most house cacti produce flowers. These flowers can be vibrant and beautiful but might only last for a day. Nivosa and prickly pear are examples of cacti that stay a manageable or small size inside the home and bloom with bright flowers.
The potential size of the house cacti also should be a consideration. Unlike some other indoor plants, it is hard to train a cactus to a specific height. Some cacti can grow to 20 feet (about 6 meters) in height, making them impractical for most households. A Peruvian apple is an example of a cactus that is too large to be grown indoors most of the time. If the growing zone is appropriate, then it can be planted outdoors, but the plant will not survive a long, cold winter.
One of the most popular choices for house cacti is the Christmas cactus, or holiday cactus. These cacti are named because they bloom during the American Thanksgiving to Christmas season, and again near the end of winter in February. Christmas cacti are relatively small and very easy to care for.