THE CULTIVATION OF HARDY BULBS AND PLANTS. 211 



only of a whole genus, but often the wants of a particular 

 species. 



If practicable it would be best to sow all seeds of hardy 

 plants at once when ripe ; we only delay sowing for the sake of 

 convenience, because we should in the case of autumnal sowings 

 be obliged to house a very large number of pans and boxes of 

 young plants too small to pass the winter outside. Hard-shelled 

 seeds must be sown at once, also all seeds of bulbs suitable for 

 out-of-door cultivation. If seed of Colchicum, e.g., is kept only 

 a few days exposed to the air there will be not more than from 

 1 to 5 per cent, come up after a year, the rest taking up to five 

 years before germinating. However, if they are sown at once, 

 when the seed-pod splits, the number of seedlings may be 

 25 to 30 per cent, the first year, the rest taking only one or two 

 years more to show life. 



Delay sowing seeds of Lilium, Fritillaria, Tulipa, &c, until 

 spring, and you may be sure that 20 to 80 per cent, will refuse to 

 move. 



Campanulas readily germinate, and so does Ostroivskya 

 magnified, but if sowing is deferred until spring the seeds may 

 lie dormant for an entire year or may be dead for ever. 



It is the practice to cover seeds with soil to the depth of their 

 diameter or a little more, but with very few exceptions all seeds 

 of bulbs want to be covered with from half to one inch of soil. 

 To this rule the large family of Gladiolus is an exception, 

 wanting to be but slightly covered with some light soil or other 

 material. 



The influence of rain and frost on germination is very 

 remarkable. Himalayan and other Primulas, sown in a pan 

 and kept as usual under glass, may take three weeks to 

 germinate slowly and unevenly ; but if a second pan be kept 

 under the same treatment, with the difference that any time 

 after a week it be exposed to a gentle rain, the majority of the 

 seeds in this pan may be up within twenty -four hours. I have 

 even known very hard seeds, which had been sown a long 

 time, to come up suddenly after a heavy thunderstorm. Of 

 other seeds a percentage, or all, lose germinative power if 

 they once become dry during the time in which they lie 

 dormant. Clematis, Anemone, Hepatica are of this class ; 

 these should be plunged in coal ashes, fine-grained cinders, or 



