158 THE PRINCIPLES OF FLORICULTURE 



to transplant seedlings too quickly, thus giving the weaker 

 seeds time to germinate before the soil is disturbed. 



121. Relation of size of seeds to vigor of the resulting 

 plantlet. The vigor of the resulting plantlet is generally 

 in proportion to the size of the seed. This is true not only 

 between seeds of different species, as for example, pea 

 and petunia ; but it is true of different seeds of the same 

 variety. The plumper and larger the seed, the stronger 

 will be the resulting plantlet. Plants show a strong tend- 

 ency to inherit the traits of the parents, hence it follows 

 that seed-producing parents should be strong and healthy. 



122. Depth for planting seeds. The depth for plant- 

 ing seeds varies with different seeds and with their re- 

 quirements for soil moisture. Since the plantlet must 

 force its way through the soil, other things being equal, the 

 less energy required and the shorter the time needed to 

 reach the surface, the stronger the vitality of the resulting 

 plantlet. Therefore, seeds should not be planted deeper 

 than is necessary to insure the proper supply of moisture. 

 Many seeds will not germinate if they are covered at all. 

 The rule, however, is that seeds should be covered to a 

 depth about twice the diameter of the seed. 



123. Soil for seeds. A good potting soil, or one 

 which has been used for some other crop like carnations, 

 is quite ideal for seed sowing. It should have a liberal 

 sprinkling of sand to insure good drainage. If it contains 

 some finely sifted leaf-mold, the physical condition of the 

 medium will be better. Pans or flats may be used ; pans 

 are preferable when only a few seeds are sown, but flats 

 should be used for larger numbers. There should be good 

 drainage in the bottom of the flat or pan. Above this, 

 there should be an inch of coarse litter, and then the soil 

 should be compacted over this, making sure that the 



