PROPAGATION 15 



employed. Plants raised from seed do not as a rule flower so soon as 

 those which originate from cuttings or grafts. Occasionally, too, as with 

 desert shrubs like Calophaca wolgarica, the root system is ill-adapted for 

 our climate, and they are much longer-lived when grafted on plants with 

 more adaptable roots ; in the case of Calophaca^ use is made of Caragana 

 or Laburnum as a stock. 



SEEDS. 



Except where large quantities of plants are required, as is usual with 

 forest trees, quick, holly and such-like, it is not advisable to sow seeds of 

 trees and shrubs in the open ground. They are much more under control, 

 germination is quicker and more certain, if they are sown in boxes or pots 

 in a cold frame or slightly heated house. If the quantity justify it, they 

 may be sown on prepared soi-1 on the floor of a frame. Where no con- 

 venience of this sort exists the protection afforded by a cloche, or 

 handlight, in the open ground is a considerable advantage. 



Soil and Drainage. The soil in which seeds are sown should be 

 fine where it is in contact with the seed, and it should be thoroughly 

 well drained. If a pot is used, at least one-third of its depth should be 

 filled with potsherds. For fine seeds like rhododendron, the pot may be 

 at least half filled. Above the potsherds leaves or loam fibre is placed to 

 prevent the fine particles of earth running amongst them. Finally, the pot 

 is nearly filled with a light compost of loam, finely sifted leaf-soil, and sand. 

 In the case of peat-loving plants like the heath family, finely broken-up 

 peat is to be employed in place of loam. For shallow pans or boxes less 

 drainage is of course required, but except for large seeds a depth of 2 to 

 3 ins. of soil will suffice. 



A common mistake is that of sowing seed too thickly. It is a matter 

 about which no fixed rule can be laid down, and it must be left to 

 individual judgment. But young seedlings standing too closely together 

 are apt to become drawn up and weakly, and, if the weather be dull, to 

 decay through damp. Another frequent mistake is that of sawing seeds 

 too deeply. A good old gardeners' rule is that a seed should not be buried 

 more than its own depth. Thus a walnut should be buried an inch deep, 

 whilst the seeds of some Ericaceae, like rhododendrons, which are minute, 

 must not be covered at all, but simply sprinkled on the top. 



Moisture. A most important requisite for the perfect germination of 

 seeds is the provision of a uniform and proper degree of moisture in the 

 soil and in the atmosphere. There is nothing more harmful to minute 

 seedlings than rapid fluctuations between dryness and saturation. Large 

 robust seeds like acorns or most of the pea family are not so susceptible 

 as the more minute and delicate ones. The ingenuity of the cultivator 

 may be exercised to secure as uniform a condition of moisture as possible. 



