Alternative substrates for the production of container-grown Mexican cempaxóchitl (Tagetes erecta L.)

Objective: To evaluate substrate mixtures for the production of Mexican marigolds grown in containers in the community of Santa Cruz Itundujia, Oaxaca, Mexico. Methods: Four mixtures were tested: 1) 70% ocote pine needles30% soil, 2) 70% leaf mold30% soil, 3) 70% river sand30% soil, and 4) 70% sawdust30% soil. Mexican marigold (Tagetes erecta) var. Inca II Deep Orange plants were established in pots under open field conditions. Height, number of leaves, plant width, branching, leaf area, and number of buds were evaluated in the different phenological stages of the plant (15, 45 and 90 days after transplant). Soil fertility parameters were analyzed, and physical analysis of the substrates was performed. Results: The treatments produced differential results; ocote pine needlessoil and leaf moldsoil were the best for producing container-grown marigolds. The lowest results in yield variables were found with the river sandsoil mixture. Implications: Using local and inexpensive substrates will impact production costs for marigold farmers. Currently, a variety of commercial mixes and substrates of foreign origin are available and used for the production of container-grown plants. Conclusions: The best substrate for the cultivation of pot-grown Tagetes erecta var. Inca II Deep Orange under open field conditions were soilocote pine needles and soilleaf mold. These materials are common, cheap and easily acquired in the region, which will facilitate the production of various ornamental species in containers based on the results of this research.