CRUCIFER.^. 49 



The flowers appear in March, April, and May, 

 are pure white, large individually as compared with those of the 

 preceding, in loose clusters. Native of Switzerland. 



Hesperis {^Dame's Violet or Rocket). — This is not a numerous 

 genus in perennial species, but is of great value, on account of 

 a few varieties of the common Rocket H. 7natronalis, the great 

 beauty of which is much enhanced by the delicious fragrance 

 they possess. The single varieties of Rockets are tolerable as 

 components of the mixed border only in large collections of 

 perennials : their proper use and value, however, is in the orna- 

 mentation of open woods, banks about streams and lakes, semi- 

 wild places either in partial shade or sunshine, and shrubberies. 

 Their ornamental qualities are not of the highest character, but 

 their fragrance is welcome everywhere. The double varieties 

 are much more ornamental, and they produce a more peniia- 

 nent floral effect, while their fragrance is not inferior to that of 

 the single ones. They are fit to grace the most select position, 

 and theyare especially commendable to amateurs, whose gardens, 

 being limited, should contain only the cream of gay plants and 

 sweet. One drawback to their being universally cultivated must 

 be noticed. They are very short-lived in many soils, especially 

 those of a light sandy texture. It is often experienced that, 

 while the single varieties grow and flower v/ell in such soils in 

 a state of nature — that is, with the surrounding surface clothed 

 with herbage — the double sorts become quickly unhealthy, and 

 will not be coaxed to live for any length of time under the con- 

 ditions of cultivation or artificial keeping. lu and about large 

 towns, except the soil is very congenial, they rarely succeed 

 well, as they have a special repugnance to the smoky impure 

 atmosphere of towns and their environs. The soil in which 

 they attain their greatest luxuriance and beauty is a rich deep 

 loam, well drained, on a cool bottom. But under the most 

 liberal treatment, and in the most suitable soil, they are apt in 

 a few years to decline in vigour and ultimately die out. The 

 species is, in fact, but a rather long-lived biennial, and it is 

 consequently necessary to propagate periodically by cuttings in 

 order to keep up a healthy vigorous stock of flowering plants. 

 Cuttings may be taken at various periods and in diff"erent con- 

 ditions : when they have made a little growth in spring ; when, 

 after early flowering, the stems have been cut down and second 

 growth made ; and just when the flowers are on the wane the 

 stems may be cut over and used as cuttings. To take cuttings 

 at the first period entails of course a greater or less loss of 

 flower; but it sometimes happens that the choice lies be- 

 tween that temporarily and the total loss of stock ; and if the 



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