104 FRUIT CULTURE UNDER GLASS 



an indefinite numlDer of years. Space alone, in most 

 instances, forbids this ; and this being the case, the roots 

 have a tendency, more especially when their outward 

 extension is barred, to seek downwards, far from the in- 

 fluence of heat and air, and where the soil is constantly 

 moist. Fortunately this tendency can be counteracted, 

 for roots have the habit of going to points where they are 

 fed. 



In order, then, to keep the roots as near the surface as 

 is desirable, the most successful means is to remove, 

 at intervals of two years at least, all the inert soil that 

 is found on the surface of the border unoccupied with 

 roots. This should be carefully done with a fork, and 

 sufficiently deep to lay bare some of the roots without 

 disturbing them much. Then cover them over with a 

 mixture of fresh loam in two parts, rotten dung or horse- 

 droppings one part, and lime-rubbish or charcoal pounded 

 rather finely one part, with the addition of half a barrow- 

 ful of bone-meal to every six barrowfuls of the mixture. 

 Lay this over the roots to the depth of 6 or 7 inches. If 

 this top-dressing is kept moderately moist, the roots will 

 work upwards into it and multiply rapidly. In the heat of 

 summer a light mulching of half-decayed stable-litter 

 should be spread over it, to prevent moisture from 

 evaporating and the necessity for much watering. In 

 thus treating a border of vines that have to be forced 

 early, the top-dressing should be put on in the autumn, 

 before the border is covered up from cold and wet, and 

 the heat from the fermenting material will warm the 

 new surface-soil, and all the more encourage the roots 

 to work upwards. 



In all localities where the rainfall is great, vine- 

 borders should be protected from excessive moisture; 



