Bromeliad Classification Overview

The bromeliad family (Bromeliaceae) consists of 51 genera and about 1,500 strictly American species. They grow from the dry deserts of southwestern United States to equatorial tropical rain forests. Based on growth habits and other characteristics, Bromeliaceae is divided into the subfamilies Pitcairnioideae, Tillandsioideae and Bromelioideae.

Members of the subfamily Pitcairnioideae are mainly terrestrial plants with heavy spines on their leaf edges. They grow in soil or on rocks and do not have a leaf rosette that traps water. The genera belonging to this subfamily commonly cultivated are Dyckia, Hechtia, Pitcirnia and Puya.

The subfamily Tillandsioideae contains the least number of genera but the largest number of species, of which many are cultivated. Plants in this group have smooth or entire leaf margins, unusual foliage markings and colors. Some species produce fragrant flowers. Plants in the genera Guzmania, Tillandsia and Vriesea are the more commonly cultivated members of this subfamily.

Bromelioideae, the third subfamily, has the most bromeliad genera grown as garden and interior plants. It encompasses 30 genera with the widest range of plant forms, and accordingly the largest number of cultivated species. Subfamily members are mostly epiphytic, leaf edges are almost all spiny, foliage has attractive markings and patterns, and the leaves are usually arranged in rosettes which may be cup-shaped. Aechmea, Billbergia, Cryptanthus, Neoregelia and Nidularium are the most popular genera of this subfamily.

Commonly Cultivated Genera

• Aechmea. Most of the 150 species in this genus are epiphytic, have deep cups to hold water and outstanding foliage all year long. The leaf edges are spined and the inflorescence are spectacular. Aechmea fasciata, one of the most popular bromeliads, is often called the urn or living vase plant because it appears to have provided a vase for its predominately pink inflorescence.
• Ananas. The commercial edible pineapple (Ananas comosus) is a member of this genus. There is a variegated form of this species (Ananas comosus variegatus) that has green, cream and pink striped leaves that form rosettes 2 feet or more across. There is a smaller species, Ananas nanus, that is commonly grown as an interior plant. It has arching, 12 to 15-inch grayish-green leaves surrounding a 15- inch spike of red buds resembling a pincushion. The buds open into purple flowers which are followed by a 2-inch high, fragrant, edible pineapple.
• Billbergia. Billbergias are tall and urn-shaped with spiny edged leaves. They are usually epiphytic and the foliage is often attractively variegated, banded or mottled. Although short-lived, inflorescence are very colorful.
• Cryptanthus. These plants are small, terrestrial, sometimes stoloniferous with flat, basal, symmetrically arranged, variously colored mottled or stripped leaves. They are grown mainly as foliage plants but their tiny white flowers, emerging low in the cups, are very attractive. Plants of this genus are commonly referred to as “earth stars” because their leaves grow low and parallel to the ground in a star-like arrangement. The species Cryptanthus bivattatus and several of its cultivators are among the most widely grown for use as interior plants.
• Guzmania. Bromeliads in this genus have thin, glossy, strap-like, smooth-edged leaves which form a water-holding rosette. There are thin brown, purple or maroon lines which run parallel along the length of the leaves. Clusters of red, white or yellow flowers appear from behind orange, yellow or red bracts on a terminal spike. They are mostly epiphytic, however, a few are terrestrial.
• Neoregelia. These epiphytic bromeliads develop blue or white flowers just above the water level in the cup. The central portion of the leaves surrounding the flowers turn rosy red. The spiny-edged leaves may also have red spots and markings. Some of the species develop red leaf tips and are often called “painted fingernail.”
• Nidularium. Plants in this genus are often confused with those in the genus Neoregelia. They both have bird’s nest type flower heads; however, Nidularium inflorescence shows the bracts rather distinctly while the inflorescence is buried in the leaf rosette of Neoregelia. These medium-sized, epiphytic plants have broad, flexible, lightly spined leaves that form an open rosette.
• Tillandsia. With nearly 400 species this genus is the largest, most diverse and widely distributed genus in the bromeliad family. Most are epiphytic, except for a few species that grow on rocks. Plant species vary in size from tiny to large. Some species have leaves that are tough and string-like; others have soft, thin, strap-like leaves. In still others the lower part of the leaf is spoon shaped. Often, the leaves are covered with a gray fuzz or scales. The inflorescence is spectacular in some species consisting usually of blue flowers with brightly colored bracts.
• Vriesea. With more than 200 species this genus is the second largest but most hybridized and cultivated genus in the bromeliad family. These are medium size, mostly epiphytic plants with soft or firm, variously green but often spotted, blotched or distinctly marked leaves. The usually long-lasting inflorescence have yellow, green or white flowers and brightly colored bracts. The inflorescence may be upright like a spear, pendulous or even curved. Plants in this genus are very susceptible to injury from cold temperatures.

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