NuMex Crimson was developed by Chris Cramer and Joe Corgan of the Department of Agronomy and Horticulture. NuMex Crimson is an open-pollinated, single-centered, high yielding, bolting resistant, red flat globe onion for fall seeding in southern New Mexico. NuMex Crimson originates from an intercross between Kurenai, Rojo, Red Grano selections from a bolting resistant selection of Texas Early Grano 502 PRR, selections from Peckham Yellow Sweet Spanish , and selections from Henry's Special crossed with Peckham Yellow Sweet Spanish in 1989. Seed was collected from the Kurenai parent and planted. The following year, bulbs with excellent red color were selected. The selected bulbs were intercrossed and the resulting seed was planted in 1991. In 1992, 1994, 1996, 1998, and 2000, selections were made using phenotypic recurrent selection, and each year's selections were intercrossed to form the next generation. For each selection, red bulbs that possessed early bulb maturity, uniform maturity, pink root resistance, bolting resistance, round bulb shape, uniform shape, hard bulb firmness, and excellent red scale color were selected. For the last two selections, bulbs were selected that possessed a single growing point when cut transversely at the vertical center of the bulb.

NuMex Crimson is a short-day, flat globe onion that matures from May 24 to May 29 when fall seeded in Las Cruces, NM. Suggested planting dates at Las Cruces are September 15 to October 1. NuMex Crimson has excellent external and internal red scale color, excellent bolting resistance, high percentage of single centered bulbs, a flat globe shape, and a higher bulb yield than other red cultivars.

Replicated field trials were conducted in 1997-1998 (NMSU 97-7), 1998-1999 (NMSU 97-7), 1999-2000 (NMSU 99-29-1), and 2000-2001 (NMSU 99-29-1) comparing NuMex Crimson to Cardinal, an F1 hybrid. The results showed that NuMex Crimson produced a similar maturity date and bolting resistance as compared to Cardinal. In half of the years tested, NuMex Crimson had a lower pink root severity and incidence than Cardinal. In each year, NuMex Crimson had a lower Fusarium basal rot severity and incidence than Cardinal. The percentage marketable bulb yield and average bulb size of NuMex Crimson and Cardinal was similar. In two years, the marketable yield of NuMex Crimson was greater than the yield of Cardinal. NuMex Crimson produced a higher percentage of single centered bulbs than Cardinal for each year.

Currently, NuMex Crimson is being offered for exclusive release to an interested party. Interested parties should contact New Mexico Crop Improvement Association, MSC 3CI, Las Cruces, NM 88003.