ROSES UNDER GLASS. 155 



Six's Thermometer, which registers the rise or fall in 

 temperature. This is one of the many thermometers 

 made for horticultural purposes, and for the green- 

 house it is unequalled. Remember, everything will 

 depend upon your thermometer, so get a good make ; 

 they are not dear, and they should last a lifetime. 



With the consideration of temperature we must 

 also consider the equally important problem of correct 

 moisture in the atmosphere of a house. To keep a 

 house too dry is to court insect pests, such as red 

 spider, thrips, and aphis, while if too moist there is 

 the great danger of mildew. I think that two 

 syringings a day — that is, in the morning and after- 

 noon — is sufficient in addition to the watering of the 

 trees. Ventilation is of supreme importance, for care- 

 less ventilation, to my mind, is the principal cause of 

 mildew. Plants get checked in growth very easily, 

 and this is bad for them when they are growing 

 strong. 



Do not open your house in frost or fog, and avoid 

 as far as possible cold, cutting winds. When the days 

 are mild give plenty of air, but at all times watch the 

 thermometer. In tfte watering and syringing of all trees 

 see that the water is of the same temperature as the 

 house; this is one of the secrets of the successful cul- 

 ture of the Rose under glass. In feeding the trees, I 

 would advise the use of artificial manure as described 

 in the chapter dealing with the subject ; but this should 

 not be applied until the trees are making strong 

 growth and are showing bud; even then I should not 

 advise too strong a liquid. Regular watering and 

 feeding is most necessary. Do not let the soil get 

 sodden, else when your flower-buds are forming they 

 will damp off. 



If mildew does appear, dust over the foliage with 

 flowers of sulphur through a fine muslin bag, or spray 

 with Abol, or Cooper and Nephews' V2K. For all 

 insect pests under glass use Darlington's " Auto- 

 shreds " ; this fumigant is the finest and safest fumi- 



