What it is
Iron-Clay Cowpea (Vigna unguiculata) is in the Fabaceae (Legume) family. The go-to summer legume cover for the South — fixes nitrogen and builds soil through the hottest months.
How to grow it
It wants full sun, water it low — drought-tough, and give it tolerant, even poor soil. Target a soil pH around 5.5–7.0. Space plants about Broadcast apart. Expect roughly Summer cover. Warm-season annual.
How it's used
Iron-Clay Cowpea is used: cover; seed edible.
🔎 How to identify it
- Three-leaflet leaves
- Pale flowers
- Sprawling habit
Edibility
How to grow & propagate iron-clay cowpea
Everything I've worked out about starting this one, keeping it alive through a Texas year, and turning one plant into many — free.
How to propagate iron-clay cowpea
Legumes resent transplanting — that taproot wants to go straight down — so sow them right where they'll grow once the soil has warmed. Soak hard-coated seed overnight to speed germination. As a bonus, this whole family pulls nitrogen out of the air and banks it in the soil, so wherever you grow them you're feeding next season's crop.
Growing iron-clay cowpea in Texas
Give it full sun and tolerant, even poor soil. Match the spot to the plant and most of the battle is already won.
This one thrives in heat that flattens other plants, so it earns its space through a Texas summer. Get it established before the worst of July, keep water steady, and it'll produce when little else will.
Once it's rooted in, this is a low-water plant — overwatering does more harm than drought here. Water deeply to establish, then back off and let it prove how tough it is.
Harvesting
Figure on roughly summer cover before you're harvesting. The part you're after: seed (as southern pea).
Making more for free
If you want more, let your healthiest plants mature fully and collect the seed once it's dry on the plant — then store it somewhere cool, dark, and dry until next season.
Part of the free Texas Roots plant database, compiled by Jordan Polasek from his greenhouse in El Campo, Texas. Free to read and share. If it helped, the best thanks is to grow something.