About Cowpeas / Iron-Clay Peas
Cowpeas and iron-clay peas are fast-establishing warm-season annual legumes that provide high-protein forage (20–28% crude protein) from mid-summer through fall and tolerate heat, drought, and low fertility better than soybeans. The vining growth habit regrows after browsing more readily than soybeans, making cowpeas a better choice for small plots or areas with very high deer pressure. Iron-clay peas are a specific open-pollinated variety of cowpea developed for vigorous vine production and soil improvement; both types should be inoculated before planting.
How much Cowpeas / Iron-Clay Peas seed per acre?
The standard broadcast seeding rate for Cowpeas / Iron-Clay Peas is 70–90 lbs per acre, dropping to about 45 lbs per acre when drilled. 70–90 lb/ac broadcast; 40–50 lb/ac drilled. Iron-clay peas are slightly smaller-seeded than standard cowpeas — check seed size. Inoculate with cowpea-specific rhizobium. The calculator above scales this to your exact plot size and converts it into the number of retail bags to buy.
When to plant Cowpeas / Iron-Clay Peas
Cowpeas / Iron-Clay Peas is a warm-season crop. In the northern US, plant in late May–Jun; farther south, plant in Apr–Jul. Sow it 1" deep and plan on 60–90.
Soil, pH & fertilizer
Aim for a soil pH near 6.2(don't go below ~5.8). No N (nitrogen-fixing); inoculate seed. Apply P and K per soil test. More drought-tolerant and less soil-demanding than soybeans. Not sure where your soil sits? Read our soil test & lime guide.
Cowpeas / Iron-Clay Peas blends well with lablab, soybeans, grain sorghum, sunn hemp, corn if you want a more diverse, resilient plot.
Cowpeas / Iron-Clay Peas FAQ
- How much Cowpeas / Iron-Clay Peas seed do I need per acre?
- Broadcast Cowpeas / Iron-Clay Peas at about 70–90 lbs per acre, or 45 lbs per acre if you drill it. 70–90 lb/ac broadcast; 40–50 lb/ac drilled. Iron-clay peas are slightly smaller-seeded than standard cowpeas — check seed size. Inoculate with cowpea-specific rhizobium.
- When should I plant Cowpeas / Iron-Clay Peas?
- In the northern US plant in late May–Jun; in the South plant in Apr–Jul. Expect 60–90.
- What soil pH does Cowpeas / Iron-Clay Peas need?
- Cowpeas / Iron-Clay Peas does best at a soil pH around 6.2 (minimum ~5.8). No N (nitrogen-fixing); inoculate seed. Apply P and K per soil test. More drought-tolerant and less soil-demanding than soybeans.
- Do deer like Cowpeas / Iron-Clay Peas?
- Deer preference: high — rapidly browsed; vine regrowth tolerates heavy pressure better than soybeans; protein 20–28%.