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THE FLOWER GROWER'S GUIDE. 



to within a few degrees of the freezing-point occasionally, but if this is often repeated 

 the chances are that a marked deterioration in the value of the plants will soon take 

 place. A safer rule would he to keep the hot-water pipes sufficiently warm to maintain 

 a temperature of 40° on cold nights and 45° on mild nights, the day temperature vary- 

 ing from 45° to 50° according to external conditions. Enthusiastic amateurs, however, 

 are apt to err in the direction of giving too much rather than too little fire-heat in the 

 winter, especially when they first obtain an apparatus. A gentle warmth in the pipes 

 keeps the air in the house genial and moving. Without it the atmosphere is stagnant, 

 cold, and damp. A little top air ought to be given on mild days. 



Plants in Pits and Frames. 



Much that has been advanced as to the watering and shading of plants in green- 

 houses also applies to those placed for a time in pits and frames. When only a change 

 of air is needed, or enough fresh air to dispel damp and to keep down the temperature 

 somewhat, raise the cap ventilators of span-roofed frames, and in all other cases either 

 block up the lights at the back or slide them down a few inches. Blocking them 

 open in front admits a rush of cold air to an injurious extent, and if the temperature 

 cannot be kept sufficiently cool by raising the lights higher at the back, block them up 

 at the sides rather than in front. 



During the hottest part of the year plants will thrive the most satisfactorily when 

 set on a cool moist bed of ashes, but when the days are shorter and the nights longer, 

 the majority may well be raised on wooden stagings or inverted flower-pots, so as to 

 bring them near the glass, where they will get more light and warmth and be less liable 

 to damp off. It economises fuel to mat over 'heated pits in severe weather; those not 

 heated, and frames generally that contain greenhouse plants, should have a heavy pro- 

 tection of mats and strawy litter as well, the sides also having some of this banked 

 against them. Never uncover till the frost is quite out of a pit or frame, and if 

 by chance the occupants are found in a frozen state, syringe them freely with cold 

 water and keep them heavily shaded till they are recovered. Sudden thaws are 

 ruinous. 



