Growth and Flowering Response of Container Grown Passion Flower Cultivars to Fertilizer and Paclobutrazo

Abstract

The effects of fertilizer and paclobutrazol applications on growth and flowering in four container grown passion flower cultivars ( Passiflora ‘Amethyst’, Passiflora ‘Blue Bouquet’, Passflora ‘Fledermouse’, and Passflora ‘Lady Margaret’) were evaluated. A four month production system was used that included propagating cuttings in late winter, followed by greenhouse liner production in early spring, and finally by two months of outdoor container production. Shoot growth was increased by increasing fertilizer rates and the response was highly cultivar dependent. Fertilizer rates resulting in the highest levels of growth for each cultivar were generally higher than those required for most container grown nursery crops, ranging between 3.2 and 5.3 g/liter (0.44 and 0.73 oz/gal) of Osmocote 14N–6.0P–11.6K (14–14–14). Paclobutrazol reduced overall plant size without increasing the number of nodes or flowers. Cultivars were chosen based on cold tolerance and vigor and cultivar appeared to be the most significant independent variable. Of the cultivars evaluated ‘Lady Margaret’ was most suitable for the four month production system.