12 BEGINNER'S BOOK OF GARDENING 



Offsets and Crowns 



An offset is a crown of leaves, generally borne near 

 the surface of the ground, which after a while becomes 

 detached from the parent plant and begins to lead a 

 separate existence. The commonest example of the 

 method of division is afforded by the house-leeks or 

 sempervivums. 



Nearly all perennial plants may be increased by simply 

 dividing their root-stock into as many parts as there are 

 eyes or crowns. At the end of every season the root- 

 stock of most perennial plants and bushes develops on 

 each branch a terminal bud. This bud or crown can 

 usually be separated with more or less root attached, 

 and may then be treated as an independent plant. In 

 some cases, as in that of the lily-of-the-valley, these 

 crowns may be separated in the autumn and treated 

 almost exactly as bulbs. 



Layers 



Many kinds of plants may conveniently be increased 

 by a method known as layering. Shoots or runners 

 from the parent plant fall over and lie on the surface of 

 the ground, and then become either naturally or artificially 

 covered at a certain point by leaves or earth, and emit 

 roots where the joint touches the ground. Eventually 

 this branch separates or may be separated from the 

 parent plant, and forms a new individual. The practice 

 of layering affords one of the simplest methods of 

 propagation in the case of suitable plants, for the young 

 layer plants are nursed by the parent until their roots 

 have become established and they can fend for them- 

 selves. Among our native plants which naturally in- 

 crease themselves in this way the blackberry and 

 strawberry are perhaps the commonest examples. In 

 the garden, plants which it is proposed to increase by 



