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nature of the plant will allow, and the soil in which they are inserted 

 should be as high as the roots will endure. The more completely these 

 conditions are maintained the greater the certainty of success, and with 

 ordinary care few failures need occur. 



" Bottom heat," as it is termed, or a warming of the soil, may be at- 

 tained by various means. Those whose requirements are extensive 

 usually have a structure specially fitted for the purposes of propaga- 

 tion, where the soil is heated by hot water either in pipes or wooden 

 or cement tanks. The latter mode is perhaps the best ; but where the 

 quantity desired is limited to the wants of an ordinary flower garden 

 or greenhouse no special structure need be necessary. A small hot 

 bed, with frame, will afford considerable convenience ; and those who 

 have a greenhouse may form one of the best propagating shelves 

 by inclosing a portion of the heating channel, whether flue or pipes, at 

 the warmest end, so as to form a tight chamber, with the heater pass- 

 ing through it. Usually there is a front shelf in greenhouses over the 

 heating apparatus, so that by simply inclosing a space below it an air- 

 chamber will be formed, where the heat will collect and warm a bed of 

 sand or soil laid on the shelf. For all ordinary purposes this will be 

 found sufficient, and the space can be enlarged to suit the wants of the 

 propagator. 



SOWING SEEDS. 



The Department is frequently in receipt of letters wherein the writers 

 complain of their inability to raise plants from seeds distributed by it, 

 as well as from those procured from other sources. The cause of fail- 

 ure is at once attributed to the quality of the seeds, and the source 

 from whence they were obtained is denounced for sending out a bad 

 article. It is safe to state that good seeds are the rule, and bad seeds 

 the rare exception. So far as the Department is concerned, there is 

 proof of their good qualities, as most of them are germinated and the 

 plants grown here ; and every respectable seedsman in the country uses 

 all the precautions that experience and business competition suggests 

 in order to secure seeds of the best quality. The truth is that they fail 

 to germinate because they are improperly managed ; and of all the causes 

 of failure the most frequent is that of covering them too deeply with 

 soil, where they either rot, owing to the excess of water and want of air, 

 or the feeble germ is unable to overcome the weight of soil it has to 

 move before reaching the light. The proper depth for each seed must be 

 judged by its appearance. The rule has been given to cover with a depth 

 of soil equal to the diameter of the seed, which is probably as nearly 

 correct and as definite as can be reached. The greatest difficulty is in case 

 of small seeds, which succeed best when merely scattered on the sur- 

 face and pressed into the soil. In the moist atmosphere of a greenhouse 

 or similar structure they will do very well; but when sown in the open 



