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CASSELL'S POPULAE GARDENING. 



placing a black mark against the weakly or miffy 

 growers. Very little experience will suffice to show 

 whether the weakness arises from bad culture, or 

 has its deeper roots in the constitution of the Rose, 

 or local climate. If the former, it may easily be 

 removed by a change of soil or of treatment ; if the 

 latter, it is almost impossible of cure, and is seldom 

 worth the trouble involved in the effort. 



From these general principles it will be well to 

 proceed to notice the particular diseases of the Rose, 

 and the best means of preventing or curing the 

 same. They are chiefly frost-bites, canker, extra- 

 vasated sap, mildew, and red rust, or orange fungus, 

 gout, and suckers. 



Frost-bites.— In our fickle climate these are 

 marvellously common, and they are also among the 

 most powerful of all causes of mischief among Roses. 

 The multiplication of Perpetual and very late-bloom- 

 ing Roses has greatly weakened the cold-resisting 

 powers of the Rose, and opened out, as it were, the 

 citadel of life to the ingress of cold. The hardiness 

 of most plants may be measured by their dormancy, 

 hardly any being frost-proof when in a state of actual 

 growth. Hence the mischief wrought by early spring 

 frost among late autumnal-blooming Perpetual and 

 Tea Roses. At first sight only the flower seems cut 

 off, which may seem a small matter, but generally 

 the entire length of the wood is ruptured or injured 

 from base to summit. These injuries are frequently 

 unseen at the time, but as growth becomes active 

 in the spring the frost-bites develop on the shoots 

 into irregular-looking scars or bruises, that often 

 destroy what seemed the most promising shoots. 

 Fortunately for Rosarians, several simple antidotes 

 to frost-bites are within reach — a paper cap, a wisp 

 of straw, or long dry litter from stable manure, or, 

 best of all, a small handful of the dried tops of the 

 common Bracken, suffice to carry the tops of Tea and 

 other tender Roses safely through frosts that have 

 wrecked those unsheltered close hy. 



Canker. — Roses are not, as a rule, subject to this 

 dire disease, though it occasionally affects them. 

 When it does it mostly arises from frost-bite, or 

 extravasated sap. It has, however, been so fully 

 treated under diseases of the Apple, that readers are 

 referred there for full practical instructions as to the 

 best remedial measures. In severe cases an entire 

 change of soil, site, and a fresh start with new 

 plants, is the best course. 



Extravasated Sap. — This is apt at times to 

 follow on the heels of severe frost-bites and bar- 

 barous pruning, and it increases the evils of the other 

 two, and hastens the disease or destruction of the 



Rose wood. The sap is mostly excessive in quan- 

 tity or infei'ior in quality when it is thus forced 

 through the bark, wood, or leaves. A poor con- 

 dition of growth, or plethoric condition of the sap, 

 is mostly the chief cause of this disorganisation or 

 disease. The sap being rather excessive in volume, 

 and often inferior in quality, is the moi'e easily 

 arrested by artificial or natural constrictions of stem 

 or branch, wounds, bruises, frost-bites, drought, 

 sudden alternations of heat and cold, &c. By mode- 

 rating the volume of sap by root-pruning, or semi- 

 starvation, by withholding water, &:c., so far as prac- 

 ticable, there will be less danger of its oozing through 

 in unnatural places, such as wood, bark, or surface 

 of the leaves. Of course, all such abnormal diver- 

 sion of sap from its normal courses and functions 

 results in the debility and disease of the Rose-trees. 

 A species of gangrene on the stem, and honey-dew 

 on the leaves, is the direct product of the extravasa- 

 tion of the sap. The latter is not only a disease, 

 disorganising the natural functions of the leaves, 

 but it also acts as a decoy for Aphides, which come 

 in such strength to feast on the houey-dew, that not 

 a few have thought the Aphides the cause rather than 

 an indirect effect of it. Very possibly, however, they 

 are both to a considerable extent ; as their feeding on 

 the leaves causes more saj) to escape, and thus the 

 insect pests and the food for them grow in strength, 

 to the corresponding weakening and iujury of the 

 Roses. 



Honey-dew should be at once sponged or washed 

 off, as otherwise its clammy saccharine qualities 

 completely block up the pores of the leaves, and 

 prevent them from performing any of their vital 

 functions. The block is made the more thorough 

 and severe by the excrementitious matter that the 

 Aphides leave behind after consuming the honey- 

 dew. This enforces the need of prompt cleansing of 

 the leaves. But this is simply a local remedy. A 

 more radical and constitutional one consists in 

 watering the roots with a very weak solution of salt 

 and water, at the rate of about a quarter of an ounce 

 to a gallon, or a little old brine in the water. 

 Whether this acts as a check on the ' absorbing 

 powers of the roots, or shortens the supplies sent to 

 the plant — that is, the leaves — is uncertain. Pos- 

 sibly it does both to some extent ; but assuredly salt 

 water tends to check honey-dew, and the oozing 

 through of the sap in unnatural places and states 

 generally, and as a remedy is as useful as it is safe, 

 provided always that it is sufficiently weak. 



Mildew. — This is one of the most virulent dis- 

 eases among Roses in many places. Certain soils 

 and sites favour its production and rapid develop- 

 ment. If not absolutely so infectious as it is mostly 



