The foliage of a plant basically refers to the leaves of a plant. A horticulturist might divide plants into flowering plants or foliage plants. However, that distinction can be confusing because many of the foliage plants do flower. If a plant is considered to be a foliage plant it is because the leaves of the plant are exotically colored or have an interesting structure.
One way to identify houseplants by foliage is to consider the color of the foliage. Once you have narrowed the plant down by color of the leaves, you can use the Internet or a plant identification book to help you identify the plant.
Purple foliage—one of the only indoor plants that features purple foliage is the Aeonium. This gorgeous plant might remind you somewhat of an open artichoke heart. The dark purple leaves are succulent and form leaf rosettes at the end of the branches. These plants can survive as houseplants, or they can be used as bedding plants in areas that don’t experience freezing temperatures in the wintertime.
Silver variegation—silver variegation or silver-lined plants have an appealing multicolored foliage. There are several of these plants, the most popular of which are the aichryson and the silvery spider plant. The aichryson is a succulent plant with diamond-shaped leaves that are dark green in the middle and silver-lined. The plant forms a yellow star-shaped flower in early summer. Unfortunately, this plant is very fragile and hard to grow. The hearty spider plant may be a better option if you don’t have a green thumb. This plant is very common and grows well in sun lit conditions.
Grey—an easy to grow plant with grey foliage is the partridge-breasted aloe plant. This plant likes plenty of sun and well-drained soil and is easy to grow. The leaves are distinguishable from other aloe plants because of their banded and white marked appearance. The blades are broad and thick, broader than other aloe plants but not as thick as some of the varieties. Because they aren’t as thick, this plant might be more difficult to identify as an aloe Vera plant.
Greens—as you have probably already discovered, most indoor plants, or houseplants feature green foliage. The different green colors can be broken down into different green shades that might help you to identify the plants. Plants that have dark green foliage include the century plant, the weeping fig, and palm plants. Plants with medium green foliage include the most ferns, lilies, and ivies as well as the more exotic plants like the Venus flytrap and the rosary vine. Light green foliage is found on the tree aeonium, the orchid, and the cape leadwort.
In general, the color of the foliage is not as good of a clue for identification as are other clues. You can use certain websites to combine clues when you are trying to identify a plant. For example, the gardening page at the bbc.co.uk website allows you to search by using several different clues. You can put the flower color, foliage color, and other features into the web form and search for pictures that meet your description.
When trying to identify houseplants by the foliage you might have more luck describing the characteristics of the leaves. Leaves have distinguishable patterns and shapes that are often used in identifying and describing common houseplants. Outdoor plants have a bigger variety of foliage than do indoor plants. If you are interested in adding beautifully colored leaves to your indoor garden, you might consider some of the outdoor plants. For example, the canna lily or canna Tropicana is a plant with beautiful green and red striped leaves. If you are very careful, you might get one to grow indoors.