GROWING PLANTS WITHOUT SOIL FOR EXPERIMENTAL USE 



Table 2. — Light, temperature, and humidity requirements and development of selected plants 1 



Species 2 



Conditions used in growth chambers 



Temperature 

 Illumination Photoperiod (day-night) Humidity 



Plant development under average 

 greenhouse conditions 



Height in — 



4 weeks 8 weeks 



Bloom Maturity 



Ft.-c. 



Alfalfa 1,500 



Barley 1,600 



Barnyardgrass 2,200 



Bean 'Black Valentine'. 1 , 500 



Beet 1,200 



Bermudagrass 1,200 



Bluegrass 1,200 



Broadbean 1,200 



Broccoli 1,400 



Buckwheat 1,400 



Cabbage 1,400 



Carrot 1,200 



Corn 1,600 



Cotton 1,800 



Cucumber 1,400 



Dill 1.200 



Endive 1,200 



Fall panicum 1,200 



Flax 1,400 



Head lettuce 1,600 



Johnsongrass 1,600 



Leaf lettuce 1,600 



Limabean 1,500 



Melon 1,400 



Millet 1,800 



Mustard 1,400 



Oat 1,600 



Okra 1,500 



Parsnip 1,200 



Pea 1,200 



Peanut 1,600 



Pepper 1,400 



Pigeongrass 2,200 



Pintobean 1,500 



Plantain 1,200 



Potato 1,400 



Red clover 1,200 



Rice 1,600 



Sorghum 1,800 



Soybean 1,600 



Spinach 1,400 



Squash 1,400 



Sudangrass 1,800 



Sugarbeet 1,200 



Sugarcane 1,800 



Sunflower 1,600 



Sweetpotato 1,400 



Swiss chard 1,400 



See footnotes at end of table. 



Hours 



°C. 



Percent 



Cm. 



Cm. 



Days 



Days 



14 



26-20 



40 



20 



36 



Tti 



100 



16 



30-20 



40 



25 



61 



60 



90 



14 



30-25 



50 



30 



55 



50 



70 



12 



20-15 



60 



36 



.. 



30 



3 65 



12 



25-20 



50 



.. 



30 



.. 



120 



12 



26-20 



50 



8 



15 



7.-) 



90 



12 



26-20 



40 



8 



20 



75 



90 



14 



20-10 



50 



30 



70 



45 



85 



12 



23-18 



55 



20 



36 



_. 



4 120 



12 



26-20 



50 



15 



55 



35 



70 



12 



23-18 



55 



15 



36 



.. 



4 120 



12 



23-15 



50 



10 



30 





85 



14 



30-25 



70 



76 



183 



56 



105 



14 



30-25 



40 



20 



51 



50 



90 



14 



30-23 



50 



.. 



.. 



35 



60 



12 



30-23 



55 



15 



81 



60 



100 



12 



23-16 



do 



10 



.. 



__ 



4 70 



12 



23-16 



in 



15 



.. 



40 



70 



12 



30-20 



50 



'_'() 



til 



45 



85 



14 



23-16 



60 



12 



.. 



_. 



To 



14 



30-23 



60 



122 



.. 



10 





14 



25-18 



tin 



__ 







60 



12 



20-15 



40 



30 



.. 



40 



7.-) 



14 



30-23 



50 



.. 





35 



60 



14 



30-23 



40 



20 



86 



til! 



100 



12 



23-18 



55 



15 



50 



60 





16 



30-20 



40 



25 



70 



70 



100 



14 



30-20 



50 



30 



til 



50 



80 



12 



23-15 



50 



36 





30 



60 



12 



20-15 



50 



36 





30 



60 



14 



30-25 



in 



15 



36 



42 



100 



14 



30-20 



50 



.. 



30 



60 



85 



14 



30-25 



50 



25 





10 



is:, 



12 



20-15 



t;o 



36 





:•;<) 



65 



12 



25-20 



40 





15 



To 



90 



12 



21-16 



10 



1.". 



61 



50 



75 



12 



21-16 



50 





20 



80 



110 



14 



30-25 



70 



30 



76 



75 



105 



14 



30-23 



40 



20 



86 



60 



100 



12 



30-20 



40 



36 



56 



35 



80 



12 



25-20 



55 



.. 



25 



50 



.- 



14 



30-23 



40 





__ 



35 



BO 



14 



30-23 



-Hi 



20 



86 



60 



100 



12 



25-20 



50 



10 



36 





120 



14 



30-25 



50 



8 



38 



__ 



140 



14 



30-25 



30 



76 



178 



56 



100 



12 



25-20 



50 



15 







85 



12 



25-20 



60 



10 



30 





-. 



