NuMex 6-4 Pepper

The NuMex 6-4 Pepper is an open-pollinated cultivar of Capsicum annuum developed in Las Cruces, New Mexico. Released in 1957 by Dr. Roy Nakayama at the New Mexico Agricultural Experiment Station, the cultivar was selected directly from New Mexico No. 6 to provide growers with elevated yields and superior pod uniformity. It produces elongated, tapering pendant pods that mature from green to red, offering a dependable mild pungency that averages approximately 1,000 Scoville Heat Units.

Distinguished by its medium-thick wall structure and smooth to slightly wrinkled skin, NuMex 6-4 served as a primary commercial benchmark for mid-20th-century New Mexican chile production. Its stable, uniform heat resolved the erratic pungency observed in earlier parent stock, making it a reliable crop for roasting, peeling, and canning. The open-pollinated plant retains an upright, branching growth habit that supports heavy pendant fruit sets across warm growing seasons.

Origin and Genetics

The NuMex 6-4 chile was developed by Dr. Roy Nakayama at the New Mexico Agricultural Experiment Station at New Mexico State University (NMSU) in Las Cruces, New Mexico. Formally released in 1957, the variety originated as a single-plant selection from New Mexico No. 6, a cultivar originally bred by Roy Harper and Fabian Garcia in 1950. The breeding objective focused on creating a stable, open-pollinated line with improved crop yields and a more consistent, mild heat profile than its predecessor.

Botanical Profile

Classified as Capsicum annuum, NuMex 6-4 grows as an upright, branching shrub with green foliage and solitary white flowers. The plant produces pendant, elongated pods featuring rounded shoulders that taper toward the apex, matching the classic Anaheim and New Mexican pod morphology. The fruit surfaces range from smooth to slightly wrinkled and possess medium-thick walls. As the pods develop, they undergo a complete color transition from green to deep red at full botanical maturity.

Heat Profile

NuMex 6-4 is categorized as a mild chile pepper, with pungency averaging 1,000 SHU on the Scoville scale. The selection was specifically stabilized to avoid the sudden spikes in heat common in older landraces, providing a gentle, uniform warmth that integrates cleanly into fresh and processed preparations.

Flavor Profile

The flavor profile of NuMex 6-4 is defined by sweet and earthy notes complemented by a mild, lingering pungency. When harvested at the immature green stage, the pods deliver a crisp, vegetable brightness with savory undertones, which deepen into richer sweetness as the fruit ripens to red.

Cultivation

This cultivar is adapted as a warm-season annual requiring full sun exposure and well-drained soil. As an open-pollinated and genetically stable variety, NuMex 6-4 breeds true to type from seed, making it suitable for seed saving when isolated from cross-pollinating Capsicum lines.

Culinary Applications

NuMex 6-4 is widely utilized for roasting and processing. Its medium-thick flesh allows the outer skin to blister and peel away easily over high heat, making it well-suited for whole chile rellenos, fresh green chile sauces, and commercial canning. In addition to fresh preparation, the harvested pods are routinely preserved through freezing, wet canning, or whole-pod drying.