OF SEED-SOWING. 161 



dener : but it sLould be obvious that minute seeds, 

 whose powers of growth must be feeble in proportion 

 to their size, will bear only a very slight covering ; 

 while others, of a larger size and more vigour, will 

 be capable, when their vital powers are once put in 

 action, of upheaving considerable weights of soil. 

 As, however, the extent of this power is usually un- 

 certain the judicious gardener will take care to em- 

 ploy, for a covering, no more earth than is really 

 necessary to preserve around his seeds the requisite 

 degree of darkness and moisture.* Hence the com- 

 mon practices of sowing small seeds upon the surface 

 of the soil, and covering them with a coating of moss, 

 which may be removed when the young seedlings 

 are found to have established themselves. In other 

 cases very minute seeds are mixed with sand before 

 they are sown. 



The latter practice is not, however, merely for the 

 sake of covering the seed with the smallest possible 

 quantity of soil, but has for its object the separation 

 of seeds to such a distance, that when they germinate 

 they may not choke up each other. If seedlings, like 

 other plants, are placed so near together that they 



* It may, perhaps, be as well to notice, in this place, an erroneous 

 opinion, not uncommonly entertained, that seeds must he " well" 

 buried in order that the young plants, when produced, may have 

 " sufficient hold of the ground." The fact is, that a seed, when it 

 begins to grow, plunges its roots downwards and throws its stem 

 upwards from a common point, which is the seed itself; and, con- 

 sequently, all the space that intervenes between the surface of the 

 soil and the seed is occupied by the base of the stem, and not by 

 roots. 



