Merritt rh; Kohl H c jr 1991

• Authors: Merritt rh; Kohl H c jr
• Title: Morphology of bedding plants in response to low night temperature and energy use implications
• Location: Scientia horticulturae (amsterdam), 45 (3-4). 1991. 295-302.
• Abstract: seedlings of bedding plant crops (Antirrhinum majus, dianthus chinensis, impatiens holsti, mimulus hybridus, pelargonium .times. hortorum, petunia hybrida, tagetes patula, verbena hortensis, viola tricolor, zinnia elegans) were grown in greenhouses, january-may 1987 and 1989, at day air temperatures of 27 .+-. 3.degree. c (9 h) and either 7 .+-. 3.degree. cor 18 .+-. 3.degree. c night air temperatures (15 h). morphological evaluations of the crop response to night temperatures were taken and calculations of fuel energy required to operate greenhouses at 7 and 18.degree. c were determined. crops which grew well at 7.degree. c and which were short, compact and bloom quickly were mimulus (cultivar 'yellow flower'), marigold (cultivars 'aurora', 'janie') and petunia (cultivars 'crimson', 'joy'). other croops which grew well at 7.degree. c, but took longer to bloom were geranium (cultivars 'cardinal orbit', 'orbit glow', 'pink elite', 'violet elite'), marigold (cultivars 'perfection'), pansy (cultivar cultivar 'universal mix') and verbena (cultivar 'springtime'). crops which were stunted or took too long to bloom were impatiens (cultivar 'accent'), dianthus (cultivars'big eye crimson' and 'scarlet', 'magic charm', 'princess'), snapdragon (cultivars 'liberty', 'pixie') and zinnia (cultivar 'peter pan'). fuel savings at 7 vs. 18.degree. c were 9.7 l of fuel oil per square meter in january, 8.8 in february, 9.6 in march and 1.8 in april.