Abstract This study determined the relationship between the amount of irrigation water applied and the yield and quality of trickle-irrigated chile peppers ( Capsicum annuum L.). From 1977 through 1983, field experiments were conducted near Las Cruces, NM. Field trickle lines were buried 5–8 cm below the soil surface and the amount of applied water was monitored with water meters. Meteorological data were gathered at a nearby weather station for irrigation scheduling. A linear relation, Y = −14.11 + 0.56 D iw with a R 2 = 0.69 was found for green chiles where Y is the green chile yield (t/ha) and D iw is the depth of irrigation water applied (cm), including rain. Maximum yields occurred between 80 and 95 cm of water applied and varied from year to year. Maximum red chile production demands the same irrigation regime as does the green chile, but the influence of fall weather may overshadow the irrigation effects. No water can be saved by stressing the plants during any period of the growing season. The pungency of the green chile peppers shows a clear trend with the irrigation treatments; the drier the treatment, the more pungent the pepper. However, other factors also play a role and may reduce the irrigation effects completely. The effect of harvest date on yield was significant, but this effect can be levelled off by harvesting twice. An interaction effect was found between row spacing and total amount of irrigation water applied.