Red clover (Trifolium pratense) is a common herbaceous plant, often identified by its distinctive leaves, typically arranged in threes, and its rounded, pinkish-purple flower heads. This short-lived perennial or biennial generally grows to heights between 8 and 31 inches.
Geographic Distribution
Red clover originated in the Old World, with its native range encompassing Europe, Asia Minor, and Northwest Africa. Human activities played a significant role in its global dispersal; English colonists, for instance, introduced it to North America by the mid-1600s.
It has since become widely naturalized across numerous continents, including North America, South America, Australia, and New Zealand. Today, red clover is cultivated and found in naturalized populations across the United States, extending from the Northeast through the Midwest and into the upper South, as well as in the Pacific Northwest. Its adaptability has allowed it to establish a widespread presence in temperate regions globally.
Environmental Preferences
Red clover thrives in temperate climates, preferring regions with moderately cool to warm summer temperatures and sufficient moisture throughout the growing season. It generally requires at least 25 inches of annual precipitation, or consistent irrigation. Optimum growth occurs within a temperature range of 68°F to 95°F (20°C to 35°C), and it is cold hardy, often surviving in USDA Zones 3-9.
The plant is adaptable to various soil types, but performs best on well-drained, fertile loamy soils. While it tolerates moderately acidic conditions, red clover generally prefers a soil pH of 6.0 or higher for optimal yields and stand persistence. It also tolerates different light conditions, growing well in full sun and partial shade.
Typical Habitats and Uses
Red clover is commonly found in various physical locations. It frequently grows in meadows, pastures, and hayfields, where it is often intentionally planted. The plant also colonizes roadsides, disturbed areas, and other grassy locations not regularly mowed.
Agriculturally, red clover is a widely used forage crop, providing nutritious feed for livestock through hay, pasture, and silage. Its ability to fix atmospheric nitrogen into the soil, through a symbiotic relationship with bacteria in its root nodules, makes it valuable for improving soil fertility and reducing the need for synthetic fertilizers. This characteristic also makes it a beneficial cover crop and green manure, contributing to soil structure and organic matter.