White Clover

White clover (Trifolium repens L.) is a short-lived perennial that can reseed itself under favorable conditions, grows rapidly, and spreads via stolons.
White Clover - Articles
White Clover

It grows best during cool, moist weather on well-drained, fertile soils with a pH between 6 and 7 (Table 1). Pure stands of white clover are not usually planted because of their low growth habit and associated low yield. However, they make high-quality pastures in mixture with a grass and fix nitrogen for use by the grass.

Table 1. Characteristics of perennial forage legumes in Pennsylvania.
Leg-
ume
Seed-
ling Vigor
Tolerance to soil limitationsHeaving potentialPersis-
tance
Tolerance to frequent:Relative maturityb
DroughtWetLow pHagrazingharvest
a pH below 6.0.
b Maturity characteristic refers to relative time of flower appearance in the spring. This will depend not only on species but also on variety.
c L = low, M = moderate, H = high
AlfalfaMcHLLHHLMEarly
Birds-
foot trefoil
LMHHLMHHLate
Red cloverHLMMMLHMMedium-late
White cloverMLHMLHHHEarly-medium

Adapted Varieties

The various types and varieties of white clover are indistinguishable from one another except for their size. Ladino and Regal are varieties whose leaf stems (petioles) grow taller than those of other white clover varieties. Because of their taller growth habit, these varieties are often referred to as large white clover types. Dutch or common white clovers have slightly shorter petioles than the large white clover types. White clovers with the shortest petioles are classified as small clovers, and their names frequently contain the words "wild white." These small white clovers yield less than the large types but persist better under heavy continuous grazing.

Establishment

White clover can be "frost seeded" (in early spring when the soil is still honeycombed with frost) into existing grass pastures to improve pasture production and quality. This technique requires that seeding be done while the soil contains frost. Delaying seeding until mid-morning when the soil surface has become slippery will result in poor stand establishment. White clover can also be no-till seeded into existing grass pastures

Seeding white clover-grass mixtures into a conventionally prepared seedbed is also an excellent method of establishment. Do not plant deeper than ¼ inch when seeding. Press wheels or cultipacking used in conjunction with or after band seeding will improve the seed-soil contact and the chances of obtaining a good stand. To obtain a proper seeding depth, the seedbed should be firm. This can be accomplished by cultipacking before seeding.

Fluid seeding (planting in a fertilizer solution) of white clover onto a well-prepared, firm, fine seedbed can also be successful. Cultipacking before fluid seeding to make a firm seedbed and after fluid seeding to ensure good seed-soil contact will improve stand establishment. Fluid seeding requires special equipment, and a custom applicator is recommended.

Seeding rates of white clover into an existing grass pasture should be 2-4 lb per acre. White clover seeds are relatively small and 1 lb of seed contains about 800,000 seeds. Therefore, the seeding rates for white clover appear low relative to other forages. Hay or silage mixtures containing white clover should also contain red clover to increase the potential yield. White clover and red clover with one of the grasses listed in Table 2 should provide an excellent hay or pasture stand.

Table 2. Seeding rates for mixtures containing white clover.
SpeciesHay or silagePasture
---lb/ A---
White clover22
Red clover35
with any one of these grasses
Orchardgrass33
Perennial ryegrass56
Reed canarygrass56
Smooth bromegrass88
Tall fescue810
Timothy45

Harvest Management

Harvesting white clover for hay or silage is generally based on the grass in mixture with the clover, since white clover constitutes a small proportion of the total forage and is of relatively high quality at maturity. Harvest should be dictated by the harvest schedule that maximizes grass performance.

Pasture mixtures that contain a legume offer many advantages but also require more careful management than pure grass pastures. Advantages of having white clover or any legume in a pasture mixture is that forage quality is improved over a pure grass pasture and the stand requires less nitrogen (N) application because of the legume's N contribution (Table 3).

Table 3. Effect of percent legume in mixture on quality of pasture in Pennsylvania.
MixturePasture qualitya
LegumeGrassWeedsCPADFNDF
------------------------------%------------------------------
a CP = Crude protein, ADF = Acid detergent fiber, NDF = Neutral detergent fibe
83611232437
741213242746
54424163153
26731123256

White clover can be grazed continuously or rotationally. It can be grazed to a height of about 1 inch without seriously damaging the stand. However, closely grazed plants must be allowed to recover. If grown with a tall-growing grass and grazed rotationally, the pastures should be grazed at intervals that do not allow the grass to shade the white clover excessively. In predominantly white clover pastures, bloat can be a problem.

Fertility

Lime and fertilizer needs of white clover should be determined by soil testing before planting. For best results the soil pH should be between 6 and 7. Starter fertilizer application of up to 20-60-20 lb per acre will often assist in white clover establishment. If the soil test calls for nutrients in excess of this amount, they should be applied prior to seeding and incorporated into the seedbed. If white clover is to be seeded into an established winter grain, topdress applications of N to the small grain should not be made.

Clover stands should be fertilized annually according to soil test recommendations. In the absence of a soil test and assuming a medium-fertility soil, apply 0-60-145 lb per acre. When white clover makes up less than 30 percent of a white clover-grass mixture, apply 30 to 50 lb of N per acre to enhance grass production.

Summary

White clover is a low-growing forage legume used predominantly in pasture mixtures with grasses. It improves forage quality above a pure grass stand and supplies nitrogen for grass growth. White clover can tolerate close grazing but persists best if allowed a period to recover. Its contribution to the total forage yield in a mixed stand is generally relatively small, but its overall contribution to forage quality and nitrogen for the grass makes it an excellent legume for pasture mixtures.

Prepared by Marvin H. Hall, assistant professor of agronomy.

Authors

Forage Crop Establishment, Management and Utilization Perennial Warm-Season Grass Establishment and Management

More by Marvin Hall, Ph.D.