Clover seeds, derived from the Trifolium genus, are widely used in agriculture and gardening for cover cropping, forage, and soil enrichment through nitrogen fixation. Identifying these minute seeds is important for ensuring the correct species is planted. Though generally small, distinct physical characteristics in size, shape, and color allow for differentiation between the many varieties.
General Physical Traits of Clover Seeds
Clover seeds are typically small, measuring between 1 to 3 millimeters in length. The shape is often described as ovoid, kidney-shaped, or somewhat heart-shaped, though this varies by species. The surface of a healthy seed is generally smooth and may exhibit a slight gloss. Color is highly variable, ranging from pale yellow or beige to darker hues like orange-brown, purple, or near-black.
Comparing Common Clover Seed Types
Distinguishing commercial clover seeds relies on comparing their relative size, shape, and color hue, as these traits are species-specific.
Red Clover
Red Clover (Trifolium pratense) seeds are typically the largest of the common varieties, often appearing elongated or somewhat triangular in shape. Their color ranges widely, frequently presenting as yellowish-brown. They can also be mottled with darker purple or deep violet patches.
White Clover
White Clover (Trifolium repens) seeds are noticeably smaller than Red Clover, making them the smallest of the widely cultivated species. They tend to be more uniformly ovoid or kidney-shaped. The color is usually a bright, pale yellow or a light orange-yellow hue, often lacking the darker mottling seen in other types.
Crimson Clover
Crimson Clover (Trifolium incarnatum) seeds fall into an intermediate size category, being larger than White Clover but generally smaller than Red Clover. The color is one of its distinguishing features, often described as reddish-yellow, straw-colored, or pale brown.
Identifying Seed Quality and Viability
Visual inspection provides important clues about a clover seed lot’s quality and likelihood of successful germination. High-quality seeds appear plump, indicating they were well-developed and possess sufficient internal reserves for initial growth. They also display a uniform color consistent with the species, and the seed coat should be smooth and intact.
Seeds that are shriveled, dull, or visibly damaged suggest poor quality, often caused by improper harvesting or storage. Discoloration, such as excessive dark spotting or a cloudy appearance, can signal deterioration or mold, which significantly lowers viability. Visual signs of insect damage or an unclean seed lot indicate the seeds may be compromised.