332 POTTING AND REPOTTING OR SHIFTING. 



a kitchen -garden, or even when placed in a hotbed, becomes too compact 

 when used in pots, even though it receives as much watering in the one case 

 as in the other. The fact is thus explained by a correspondent : When 

 the nature of the soil is such as that the cohesion of its particles is greater 

 than that which is formed between the soil and sides of the pot, it loses hold 

 of the latter, and becomes concentrated by every withdrawal of moisture, 

 leaving an almost clear cavity between it and the sides of the pot, and this 

 cavity being readily filled with water, the soil is prevented from expanding 

 in a degree proportionate to the force that would be necessary to displace 

 the water. In addition to this, the fibres of the plant tend to bind it 

 together, and it ultimately becomes so much solidified that it either refuses 

 to take in sufficient moisture ; or, if it does, it retains it so as to prevent the 

 ingress of a fresh supply ; whilst at the same time the water so retained 

 becomes impure, and consequently injurious to the health of the plant. 

 A similar quantity of soil in the quarter from which the above soil is 

 supposed to be taken will be found in a very different state ; for there it is 

 kept from contracting on any central portion by its cohesion with the soil in 

 the circumference. Hence the necessity of using such soil for plants in 

 pots as is not too cohesive ; or at all events weakening its cohesive power 

 by mixture with sand, peat, turf, or other substances that may be found to 

 answer the purpose, and at the same time afford congenial nourishment to 

 the plants. And as glazed pots afford less hold for the soil than those with 

 a rougher surface, it is probable they are on that account objectionable. 



743. Bottom Drainage. Whether plants are put in small or large pots, 

 the first point which requires to be attended to is to cover the hole in the 

 bottom of the pot with some description of material which will readily allow 

 of the escape of water, and if possible prevent the entrance of earth-worms, 

 (296). The article commonly used is fragments of broken pots, which 

 being always, excepting in the case of pot-bottoms, portions of a curved 

 surface, never can cover the hole so closely as to prevent the escape of 

 water. One crock, somewhat larger than the hole, is placed over it, and over 

 that is placed a layer of smaller pieces, in depth more or less according to the 

 size of the pot and the degree of drainage wanted ; and to prevent the soil 

 which is to be placed above from being washed down into this drainage, it is 

 commonly covered with a layer of fibrous or turfy matter obtained from 

 turfy soil, or with live moss. In the case of small plants requiring nothing more 

 than ordinary care, a single crock, or in large pots a single oyster-shell, placed 

 over the hole in the bottom of the pot is generally found sufficient ; but in 

 very delicate plants, a fourth, a third, or even half the pot is filled with 

 drainage. This, as we have seen (584), is more particularly the case in 

 planting cuttings in pots. 



744. The mode of sowing or planting in a pot has nothing peculiar in it. A 

 small dibber, fig. 16 n, in p. 131, is commonly used for planting seedlings of 

 the smallest size ; the pot being previously drained, and filled full of soil 

 gently pressed down. In planting larger seedlings, or rooted cuttings, the pot 

 is drained, filled one-third or one-half with soil, raised a little in the middle, 

 and while the plant is placed on this soil and held upright with one hand, the 

 fibres are spread over the somewhat conical surface of the soil with the other ; 

 and afterwards the same hand is employed in taking up soil with a trowel and 

 filling it in over the roots, shaking up the latter a little, till the pot is full. 

 The pot is now taken up with both hands, and set down with ajar once or twice 



