100 



PRINCIPLES OF PLANT CULTURE 



Slightly immature seeds usually germinate sooner than 

 fully-matured ones. 



164. Length of seed viability. — The viability of all 

 seeds is limited by age, but the duration of the vital 

 period varies greatly in different species. Seeds of the 

 chervil rarely germinate if much more than one year old, 

 while those of the gourd family, the tomato and celery 



Duration 

 OF Ger- 

 minating 

 Power 



Av, Ext'n 

 Yra. Yrs. 



Duration 

 OF Ger- 

 minating 

 Power 



Av. Ext'm 

 Yrs. Yrs. 



Artichoke . 6 



Asparagus ... 5 



Bean . . 6 



Bean — kidney 3 



Bean — soy . . 2 



Beet . . 6 



Borecole or kale 5 



Broccoli . . 5 



Cabbage .... 5 



Cardoon .... 7 



Carrot . 4 or 5 



Cauliflower . • i ^ 



Celery I 8 



Chervil . . 2 or 3 



Chervil — sweet- 

 scented .... 



Chervil — • turnip- 

 rooted .... 



Com salad 



Cress — American . 



Cress — common 

 garden .... 



Cress — water 



Cucumber — com- 

 mon 



Eggplant . . 



1 



5 

 3 



5 

 5 



10 

 6 



10 



8 



10 



8 



6 



10 



10 



10 



10 



9 



10 



10 



10 



6 



1 



10 

 5 



9 

 9 



10 

 10 



Endive 



Gumbo or okra 



Hop 



Kohlrabi 



Leek 



Lentils . 



Lettuce 



Maize or Indian corn 



Melon — musk . . 



Melon — water . 



Mustard — black or 

 brown . . . 



Onion 



Parsnip .... 



Parsley . ... 



Pea 



Pumpkin . 



Rhubarb . . 



Salsify 



Sea-kale 



Spinach — prickly- 

 seeded . . . 



Squash 



Strawberry 



Tomato . . . . 



Turnip . . . 



10 

 5 

 2 

 5 

 3 

 4 

 5 

 2 

 5 

 6 



4 

 2 

 2 

 3 

 3 

 6 

 3 

 2 

 1 



5 

 6 

 3 

 4 

 5 



10 



10 



4 



10 



9 



9 



9 



7 



10 



10 



9 



7 

 4 

 9 

 8 

 10 

 8 



7 



10 



6 



9 



10 



