Evaluation of Organic Fertilizers on the Growth and Yield of New Mexico Green Chile (Capsicum annuum L.)

New Mexico’s growers have the opportunity to capitalize on the increasing demand for organic produce with organic green chile production. Conventional growers have numerous commercially available options for fertilizers in both granular and liquid forms. Organic fertilizers are less available, especially in liquid form. Most conventional growers optimize timing of fertilization by fertigating through drip irrigation. Currently, the standard practices in southern NM for organic chile production is furrow irrigation and fertilization through one pre-plant application of 500 lbs/ac of granular, heat treated chicken manure. Green chile crops usually undergo two harvests and require additional nitrogen application for robust development of second-harvest fruits. Organic growers are not able to apply additional granular fertilizer for the second-harvest because plant size prevents equipment entry into the field. A liquid form of organically sourced fertilizer, like compost tea, may benefit the growth and yield of second harvest crops in green chile production. To determine plant response to organically sourced fertilizers, two hybrid green chile cultivars, G76 (Harris Moran) and Chile 1 (United Genetics), were evaluated by measuring fruit yield and quality from the second harvest in response to different treatments of organic fertilizer. Seedlings were transplanted at New Mexico State University’s Fabian Garcia Science Center in Las Cruces, NM on 2 June 2015. The experimental design was a Latin Square arranged in a 5x5 factorial treatment structure using twenty-five, 1.25 m² plots. Drip irrigation was installed so that plots in each treatment would receive the appropriate fertilizer treatment and equivalent irrigation. Each box contained eight plants of each cultivar. The treatments included: one time application of processed chicken manure (control), one time application of compost, multiple applications of compost tea, combination application of compost and compost tea (all with applications balanced to adjust for standard N application rate), and a onetime half application of processed chicken manure. Second green chile harvest occurred 116 days after transplanting. Within cultivars, no significant differences were observed in overall yield or fruit size. The organically sourced fertilizer treatments, including compost tea, produce green chile comparable in yield and fruit quality to the current standard treated chicken manure fertilizer regime. Interestingly, the half rate chicken manure treatment also provided comparable yield, indicating that organic producers may be able to reduce current application rates.