Calculate how many paddocks you need for rotational grazing, area per paddock, and the full rotation cycle duration.
This calculator designs a rotational grazing system. Enter total pasture area, animal numbers, desired rest period, and grazing period per paddock to determine the number of paddocks needed and their size. Essential for optimizing forage utilization.
A 20 ha farm with 30 cattle wants a 30-day rest period and 3-day grazing per paddock. That's (30÷3)+1 = 11 paddocks of ~1.8 ha each. Full cycle = 33 days. At 25 kg DM/ha/day growth, each paddock provides 25×3×1.8 = 135 kg DM per graze — enough for 30 cows eating 12 kg each for about 11 hours. Consider more intensive rotation or supplementation.
✓ Expert Reviewed: This calculator and its content have been reviewed by agricultural experts. Formulas are based on NRC, FAO, and university extension recommendations. For site-specific advice, consult your local agronomist or veterinarian.
Enter total pasture area in hectares, number of animals, desired rest period in days, grazing period per paddock in days, and daily pasture growth. Click Calculate.
The Pasture Rotation Calculator designs a grazing system that matches forage growth rate. Rotational grazing improves pasture utilization (from 30-40% continuous to 60-80% rotational), reduces erosion, and improves animal performance. FAO recommends matching rest periods to species regrowth.
Paddocks = (rest period ÷ grazing period) + 1. Area/paddock = total area ÷ paddocks. Cycle = rest + grazing. Rest periods: cool-season grasses 20-30 days, warm-season 30-45 days. More paddocks = shorter grazing periods = better forage regrowth and utilization.
20 ha, 30 cows, 30-day rest, 3-day graze. Paddocks = (30÷3)+1 = 11. Area each = 20÷11 = 1.82 ha. Cycle = 33 days. Daily growth 25 kg/ha. Per paddock per graze = 25×3×1.82 = 136.5 kg DM. 30 cows need 360 kg/day — shortfall. Supplement or reduce herd size.
Common mistakes: too few paddocks (overgrazing), too short rest period (weakened plants), fencing in wrong places. Tip: start with 4-6 paddocks and expand as needed. Water access to every paddock is essential. NRC recommends adjusting rest periods based on growth rate — longer in slow growth.
Formula: paddocks = (rest period ÷ grazing period) + 1. For 30-day rest and 3-day graze = 11 paddocks. Minimum: 3-4 paddocks for basic rotation. Ideal: 8-12+ paddocks for intensive management. Each additional paddock increases utilization by ~5%. More paddocks = shorter grazing = better regrowth. Start with 4-6 and expand.
Rest period depends on growth rate: cool-season grasses 15-30 days in spring, 30-45 days in summer, warm-season grasses 20-35 days. Rest must allow plants to reach 3-leaf stage or 6-8 inches before regrazing. Too-short rest weakens root reserves and reduces future production. NRC recommends adjusting rest seasonally.
Depends on forage growth: at 25 kg DM/ha/day, one 500 kg cow eating 12 kg/day needs 12 ÷ (25 × 0.5 utilization) = 0.96 ha/cow. At 40 kg/ha/day: 0.6 ha/cow. This is for daily grazing — for full year, divide annual production by annual needs. FAO recommends 1-2 cows/ha in temperate climates with good management.
Benefits vs continuous: (1) Higher stocking rate (up to double), (2) Better forage utilization (60-80% vs 30-40%), (3) Improved animal performance, (4) Better soil health, (5) Reduced labor vs harvesting feed, (6) Lower input costs. Typical investment: fencing and water systems, paid back in 2-4 years through reduced feed costs and higher production.
Options: (1) Portable water troughs moved with each paddock, (2) Permanent water lines with hydrants at each paddock, (3) Central lane with water access to all paddocks. Cows drink 40-60 L/day. Rule of thumb: water within 300 m of grazing area. Use frost-proof hydrants in cold climates. Plan for 50 L/min flow rate per 30 cows.