THE DISA GRANDIFLORA. 



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post, when they will want more water at the roots, as well as 

 over the foliage. Twice a day will do them no harm, according 

 to the state of the weather. 



March, April, and May they will take copious supplies. In 

 the latter month, if about 1 oz. of guano is dissolved to a gallon 

 of aired water, and given them once a week, they will derive 

 much benefit from it. 



The principal insects which attack the plants are red spider, 

 green and black fly, which get down the centre of the young 

 growths, and if not eradicated will soon cripple the young shoots. 

 I used to lay the plants on their sides and syringe the fly out 

 with a little soft soap and water, as tobacco smoke disfigured the 

 young leaves at the tips. But now I use that gardener's friend 

 called " XL All," a vaporiser that will kill the fly on the first 

 application without injuring the most delicate foliage, provided 

 that it is quite dry at the time of fumigation. 



Slugs are also very fond of Disas, and would soon ruin the 

 plants if not looked for in the evening. Some shell snails also 

 are very troublesome, boring holes through the tender leaves, 

 and being so very small they are difficult to find. 



About the middle or the latter end of May, if it begins to be 

 very hot, I remove the plants out of the house into a cold frame 

 on the north side, bringing them back to flower, as in the frame 

 the spikes would be too near the glass, and could not be so 

 easily inspected as in a house. During the time they are in the 

 frames, if the lights are drawn off now and again during gentle 

 showers of rain, it will do them a great deal of good. Rain- 

 water is the best to water them with if it can be got. 



The lights should be well tilted up at all times, so that they 

 can have plenty of air. If a little is left on all night, when 

 the weather is favourable, the growths will be all the more 

 robust. 



Hybeidisation. 

 I am quite sure there is a large field for the hybridist to work 

 up new varieties belonging to this Alpine genus. Messrs. 

 Veitch have already given us several new ones, for which we are 

 greatly indebted to them, such as Disa Langleyensis, the result 

 of Disa racemosa crossed with D. tripetaloides. Also the most 

 beautiful Disa Veitchii, a hybrid between Disa grandiflora and 

 D. racemosa. The sepals are of a bright carmine, with the 



