575 Greenhouse Specialty Cut Flower Production Using Bedding Plant Flats

Abstract

Three cut-flower species, Ageratum houstonianum `Tall Blue Horizon', Antirrhinum majus `Spring Giants Mix', and Helianthus annuus `Sunrich Orange' were grown in 806, 1801, or 1001 bedding plants flats resulting in 32 (85), 86 (280), and 156 (620) cm2 (mililiter medium)/plant, respectively. Plants were sown Sept. 1997 (fall), Dec. 1997 (winter), or Mar. 1998 (spring). Increasing area per plant decreased number of stems harvested but increased percent of stems harvested for all species. Increasing area per plant increased stem length and selling price for Antirrhinum and Helianthus; no significant difference was noted for Ageratum. Days to anthesis decreased with later planting for Antirrhinum and Helianthus; however, for Ageratum winter planting had the longest crop time and spring planting the shortest. Gross profit per square meter and square meter per week increased with decreasing area per plant for Ageratum and Helianthus; no significant difference was noted for Ageratum. Gross profit per square meter per week increased with later planting for all species. With all species 806 flats or spring planting required frequent irrigation, which would best be supplied by an automated irrigation system. Experiment was repeated in 1998/1999 using Carthamus tinctorius `Lasting Yellow', Celosia argentea `Chief Mix', Cosmos bipinnatus `Early Wonder', Helianthus annuus `Sunbright, Tagetes erecta `Promise Orange' and `Promise Yellow', and Zinnia elegans `Giant Deep Red' and `Oklahoma Mix'.