New Organic Cowpea ‘TAMC 101’: A Cover Crop and Forage Option for Southern Farms

by Dr. Waltram Ravelombola¹

Texas A&M AgriLife has released a new organic cowpea variety called ‘TAMC 101’, developed specifically for farms across the southern United States that are working to build soil health in hot, dry conditions.² Cowpeas have always been a dependable summer legume in our region, sprouting with very little moisture and growing through the intense heat that shuts down many other cover crops. What makes this variety stand out is that it was bred and selected entirely under organic management, meaning it performed well without synthetic nitrogen, without chemical weed control, and under real dryland field pressure. That alone makes it unusual—and useful—for organic and regenerative growers.

The story of ‘TAMC 101’ began with PI 293587, a highly variable cowpea line introduced in 1963. Breeders noticed one plant that produced noticeably more biomass than anything around it. That single plant became the foundation of this new variety. All seed increases took place in organic plots at the Vernon Research Station, and the result is a cowpea that spreads quickly, shades soil early and helps suppress weeds in systems where herbicides aren’t an option. The plants form a semi prostrate canopy with medium-green leaves, strong stems, and purple flowers—a combination that creates a full, dense stand that covers ground faster than the popular ‘Iron & Clay’ check variety.

Biomass of Organic TAMC 101 Cowpea

Across three years of trials in Vernon and Lubbock from 2021 to 2023, ‘TAMC 101’ consistently produced more biomass than the check. Its average dry matter yield was 3,850 lb/acre, compared with 3,485 lb/acre for ‘Iron & Clay’ cowpea, and in every single environment the new variety came out ahead. That extra biomass matters for weed shading, soil organic matter, and forage harvest. Nitrogen accumulation followed the same pattern. ‘TAMC 101’ averaged 74 lb N/acre, compared with 70 lb N/acre for the check, giving organic producers a dependable warm-season legume to help cycle nutrients naturally and reduce the strain on soil fertility. For growers who integrate grazing, forage quality was comparable to existing cowpea options, with crude protein averaging 22.1%, making it a solid late-summer protein boost for livestock.

What growers can appreciate most about this cowpea is how naturally it fits into real organic production. It doesn’t require high inputs, handles dry sowing well, and won’t drain soil moisture the way some summer covers can. Termination is also simple—one hard freeze ends it—which is a valuable feature for farms trying to avoid multiple tillage passes going into fall crops. For mixed crop-livestock operations, the dual-purpose role adds more value: the same cover crop that builds nitrogen can also provide emergency summer forage. In many parts of Texas, especially after wheat or oats come off, growers have a wide, hot window where they need something that can establish with little moisture and leave the soil better than it found it. This variety fits that window well.

Farmers often want a low-risk way to add summer cover crops into their system without sacrificing moisture or increasing weed pressure. ‘TAMC 101’ was developed with those realities in mind. Whether it’s planted after a small-grain harvest, used as a quick forage, or integrated into organic rotations for corn, sorghum, or vegetables, this cowpea gives producers a simple, reliable tool for improving soil health during the hottest part of the year.

For growers and seed producers interested in seed availability, licensing inquiries are directed to Dr. Richard Vierling, richard.vierling@ag.tamu.edu, Texas A&M AgriLife Foundation Seed in Vernon.

1. Dr. Waltram Ravelombola, Assistant Professor, Texas A&M AgriLife Research. https://vernon.tamu.edu/people/ravelombola-ph-d-waltram/ ↩︎
2. Ravelombola, W., Manley, A., & Cason, J. (2025). ‘TAMC 101’: New organic cover crop and forage cowpea for the southern United States. HortScience, 60(12), 2308–2309. https://doi.org/10.21273/HORTSCI18972-25 ↩︎