EASTER LILIES 13 



Blooming Dates. — The number of days required to bring Easter lily plants 

 into bloom was reduced as the rooting temperatures were increased. 

 The shortest period was approximately 100 days at a rooting temperature 

 of 70°-80° F. as summarized in Table 3. With a rooting temperature of 

 40''-50° P., bulbs required about 150 days to bloom. The rate of develop- 

 ment 98 days after potting is illustrated in Figure 1, C and D. 



Table 3. — Relation of Rooting Temperature to Length of Growth 



Period of Lilium longiflorum giganteum. 



Waltham, Mass., 1935-37. 



Rooting' Number of Average Number of Days 



Temperature Observations from Potting to Bloom* 

 Cabinets 



70-80° F 2 99-106 



60-70° F 6 116-138 



50-60° F 6 135-149 



40-50° F 1 151 



*Date of flowering represents the time when the first flower opened 

 on at least 50 percent of the plants. 



Relation of Size of Bulbs to Earliness of Floivering. — The earliness of bloom 

 was definitely influenced by the size of the bulbs. As' shown in Table 4, 

 8-10 inch bulbs bloomed approximately 10 days earlier than the 7-9 inch 

 bulbs at 52°-55° F., and 20 days earlier at 62°-65° F. Similar results were 

 obtained under both controlled cabinet and greenhouse conditions. 



Table 4. — Size of Bulbs in Relation to Date of Bloom of 



Lilium longiflorum giganteum. 



Waltham, Mass., 1935-37. 



Average Number of Days 

 Huuling from Potting to Bloom 



Tenijieratures 



Cabinets 



42-45° F 



52-55° F 



62-65° F 



70-72° F 



80-82° F 



(Greenhouse 



52-55° F 



62-65° F 



Experiments with Lilium erabu and Lilium Howardi 



The commercial varieties erabu and Howardi are generally believed 

 to require low rooting temperatures for successful forcing (6). 



As shown in Table 5, however, erabu bulbs forced at Waltham pro- 

 duced a slightly greater number of flowers and blossomed 16 days earlier 

 when they were botli rooted and grown at 62°-65° F. than when they were 



