Clover plants are a familiar sight, often found abundantly in lawns, fields, and natural landscapes. These herbaceous plants are part of the Trifolium genus, encompassing approximately 300 species, and are recognized for their distinctive foliage. Their prevalence across temperate and subtropical regions globally makes them a common encounter.
Defining Characteristics
Most clover plants exhibit a consistent visual pattern, primarily in their leaves and flowers. Each clover leaf is typically composed of three smaller leaf segments, known as leaflets, a characteristic referred to as trifoliate. These leaflets commonly display shapes ranging from oval to egg-shaped, and some, particularly white clover, often feature a pale V-shaped or crescent marking. Leaves emerge from long stalks, arranged alternately along the stem.
Clover plants generally maintain a low-growing habit, spreading by stems that creep along the ground. These creeping stems, called stolons, can root at their nodes, helping the plant to form dense mats.
The flowers of clovers are small and gather into compact clusters, which can be spherical or elongated. These flower heads are composed of many tiny florets, and their color can vary from white to pink, red, or purple, depending on the specific clover type.
Common Clover Species
While sharing general characteristics, common clover species display distinct appearances. White clover (Trifolium repens) is a low-growing perennial, typically reaching 10 centimeters (4 inches) tall. Its leaves have rounded leaflets, which frequently bear a white chevron or V-shaped mark. Its globular flower heads are white, sometimes with a slight pink tint, and tend to droop as they mature.
Red clover (Trifolium pratense) generally grows taller, often reaching 30 to 60 centimeters (12 to 24 inches) in height. Its leaflets are larger and more oval-shaped, and may also have a pale crescent or “V” pattern. Red clover stems can be noticeably hairy. This species produces rounded or oval flower heads that are rose-pink to purplish-red.
Crimson clover (Trifolium incarnatum) is an upright annual herb, commonly growing 20 to 91 centimeters (8 to 36 inches) tall. Its trifoliate leaves have hairy leaflets and generally lack white markings. Its most distinguishing feature is its vibrant, deep red, elongated, cone-shaped flower clusters, which can visually resemble strawberries.
The Four-Leaf Clover
The four-leaf clover is a well-known variation, distinguished by an extra leaflet. While most clovers have three leaflets, this unique specimen possesses four. It is not a distinct species but a rare deviation, most commonly observed in white clover (Trifolium repens).
Finding one is uncommon, with estimates suggesting a frequency of approximately 1 in 5,000 to 1 in 10,000 clovers. This additional leaflet primarily results from a genetic mutation. Environmental factors, such as temperature and soil acidity, can also influence whether this mutation manifests. Sometimes, the extra leaflet can also arise from developmental errors. The four-leaf clover has long been associated with good fortune and is widely regarded as a symbol of luck.