SEA CABBAGE 



two feet tall, much branched, the flower a yellow crucifer and the 

 silique from one to two inches long. The plant is biennial. 



Black Mustard, Brassica nigra, and White Mustard, Brassica 

 dlha, are the mustards of commerce. The seeds germinate so rapid- 

 ly that it has been extravagantly said that a salad might be grown 

 while the joint of meat was roasting. Both species are common in 

 fields throughout Evirope. The powdered seeds are used as a con- 

 diment because of a fixed and very acrid oil which they contain. 

 The seeds of White Mustard are considered more delicate than 

 those of Black. 



Other species of Cruciferm in cultivation are: 



Rock Cress, Arabis alplna, one of the earliest and prettiest of 

 spring-blooming plants; growing in tufts which are covered with 

 terminal flat-topped clusters of pure-white crucifer flowers soon 

 after snow disappears. It is a perennial of easy culture, and 

 thrives even in poor soil, but requires plenty of sun. Native to the 

 mountains of Europe. 



Arabis dlbida is also a favorite and its flowers are a little larger 

 than those of alpina. 



Whitlow Grass, Draba, is a genus of spring-blooming plants ad- 

 mirably adapted for the alpine garden. Its flowers are small 

 crucifers, white, yellow, or purple, and the leaves grow in dense 

 little rosettes. When grown in mass the plants are effective. 



False Wall Cress, Aubretia deltoidea, is a favorite plant for 

 rock work and edging. It is a perennial evergreen trailer with 

 spatulate or deltoid leaves, producing violet or purple crucifer 

 flowers in early spring. Many variants from the type are in culti- 

 vation. Native to western Asia and southern Europe. 



Wall Flower, Cheirdnthus cheiri, is not hardy in New England 

 and the idea prevails that it is not hardy elsewhere. As a matter of 

 fact it bears the winter well on the shore of Lake Erie in northern 

 Ohio, and is regarded as one of the best of early blooming plants. 

 Its color range runs through, all the yellows to orange-brown. 

 With us it lives in the garden only, but in Europe it "sings among 

 the ruined walls and covers with light the grieving stones." 



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