Planting Medium Effects on Forced Swaziland- and Dutch-grown Hippeastrum Hybrids

Abstract

The Swaziland-grown Hippeastrum bulbs `Summertime' and `Sun Dance' reached the market and flowering stages of development in fewer days than the Dutch-grown bulbs `Apple Blossom' and `Red Lion'. `Sun Dance' was the quickest flower and `Red Lion' the slowest. The effects of the planting medium on days to market and flowering were variable and no medium appeared to be the best for this criterion. `Summertime' and `Red Lion' produced longer leaves at flowering than `Apple Blossom' and `Sun Dance'. Three media that led to the production of the longest leaves, a desirable trait, were: Sunshine no. 4, Fafard 3-B, and Sunshine Post-Harvest. `Apple Blossom' was the tallest cultivar followed by `Sun Dance', `Red Lion', and `Summertime'. Effects of the planting medium on total plant height were variable. The overall plant quality ratings for use as potted plants ranged from 3.4 to 3.8 out of 4 for `Summertime', `Sun Dance', and `Red Lion'. `Apple Blossom' was rated 3.0 because it was tall and had short leaves. It would be suitable as a cut flower. Regardless of the planting medium used, `Apple Blossom' lost the greatest amount of old basal roots. Consequently, it produced many new basal roots. The planting medium had variable effects on old and new basal roots and secondary root growth, depending on the cultivar. Based on all the flowering criteria and the rooting responses, the best media for all cultivars as potted plants were Fafard 3-B and Sunshine Mix no. 4. Fafard no. 2 was best for cut-flower usage since it produced taller plants with a good root system.