256 



THE GARDENER'S ASSISTANT. 



retained) the parts that remain are better 

 nourished, a healthier leaf-action is induced, 

 and this, reacting on the roots, brings about 

 a permanent improvement in the vigour and 

 health of the tree. See figs. 330, 331, of an 

 old Oak that has been treated in this way. It 

 may be mentioned that this result is accelerated 

 by top-dressing the roots with good soil or 

 even short manure. An occasional thorough 

 watering, too, is a great help in seasons of 

 prolonged drought. 



Pruning of Shrubs. — -The pruning of evergreen 

 shrubs merely for the purpose of keeping them 

 to some given size or shape is a simple matter. 

 The true problems of pruning scarcely arise. 

 All that is required, as a rule, is the mainten- 

 ance of some particular outline, such as in topi- 

 ary work, hedges, low banks of Laurel, &c, 

 or the restricting of individual shrubs to certain 

 dimensions. The best, and generally the most 

 convenient, time for this kind of pruning is in 

 July and August. With flowering evergreens, 

 like Berberis stenophylla, B. Danvinii, Rhodo- 

 dendrons, and such like, the case is different. 

 The succeeding crop of blossom has to be con- 

 sidered. With these the best time to prune is 

 as soon as the flowers are over. It is desirable 

 to get as long a season of growth as possible. 

 For this reason, especially with evergreens that 

 flower rather late, it may sometimes be worth 

 while to sacrifice a year's flowers and prune as 

 soon as growth commences in spring. As a 

 general rule, however, such plants do not need 

 pruning. It is only when they are outgrow- 

 ing their bounds, or getting out of shape, or 

 perhaps not in good health, that pruning is re- 

 quired. Large Rhododendrons that have been 

 damaged by transplanting, or have become thin 

 and poor in leafage, are often benefited by re- 

 ducing the growths, They may, indeed, be 

 placed in the same category, and treated on 

 the same principles, as the old trees whose re- 

 in vigoration has already been discussed. 



Irish Yews, the fastigiate Cephalotaxus, and 

 other erect-growing shrubs or small trees, often 

 consist of a mass of erect, comparatively thin 

 and weakly, growths huddled together, and are 

 very apt to blow loose and become unsightly 

 during our winter storms. This necessitates a 

 good deal of labour in tying, which may, how- 

 ever, be largely avoided by forming a central 

 stem to each plant and keeping the lateral 

 branches shortened back, adopting, in fact, the 

 same methods that have been described in re- 

 gard to large-growing trees. Hollies, Pines, 

 Spruces, Firs, and the like should always be 



kept to a single stem if the object be to obtain 

 fine specimens. 



Deciduous shrubs that are grown for their 

 flowers may, for purposes of pruning, be divided 

 into two groups, viz.: (1) those that flower on 

 wood made the previous year (which constitute 

 the great majority); and (2) those that flower 

 on wood produced during the current season, 

 such, for instance, as Sjnrceajaponica, Genista tinc- 

 toria, and Hydrangea paniculata. It is a general 

 rule with all shrubs that as long a period as 

 possible should intervene between the time of 

 pruning and the following flowering season. 

 Taking first the second group, i.e. those that 

 flower on the current season's growth — as a 

 rule from July till the end of autumn — pruning 

 has to be done in winter, or not later in spring 

 than when the first signs of growth are visible. 

 The autumn-flowering Spiraeas (S. jajwnica, &c.) 

 and Hydrangea paniculata may be taken as 



! examples. These remain in flower up to late 

 autumn, and, if undisturbed, the old flower 

 stems will remain on the plant all the winter. 

 The pruning of these shrubs consists in shorten- 

 ing back the growths that flowered the previous 

 autumn ; also, if there is a likelihood of the new 

 growths being too crowded, in entirely remov- 



' ing some of the old stems. If the plants are 

 tall enough for their position they may be 

 spurred back to within a few buds of the older 

 wood. On the other hand, small plants need 

 little more than the tips of the growths removed. 

 There are a few other shrubs, like Forsythias, 



j Chimonanthus fragrans, Primus triloba, &c, which, 

 although they flower on the wood of the pre- 

 vious year, do so early in the year before the 

 growing season commences. These also should 

 be pruned on the shortening -back system, be- 

 cause if pruning is done as soon as ever the 

 flowers are over, the whole, or practically the 

 whole, season of leaf-growth is still available for 

 them. Fig. 332 represents a Forsythia in winter 

 unpruned, with lines indicating what should be 



j cut away in April, after the flowers are over. 

 Those shrubs which belong to group 1, such 

 as Philadelphus, Diervilla, Deutzia, the earlier 

 flowering group of Spiraeas, and the like, flower 

 after the growing season has well begun. To cut 

 back the shoots of these in winter or spring would 

 be to remove the flowering wood. If, on the 

 other hand, they are spurred back after flower- 

 ing, the season of growth is curtailed and the 

 succeeding crop of flowers greatly reduced. It 

 is evident, therefore, that to merely shorten 

 back the shoots would be wrong. Pruning for 

 shrubs of this group must be mainly a matter 



