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completed. While the plant is flowering it draws principally on its 

 last-made bulb, but also on the back bulbs, each in turn drawing 

 nourishment from the next older bulb. This is easily proved 

 by observing an Onadium carrying a long spike. It is to be seen 

 that all the bulbs show signs of shrivelling, and if the spike is 

 bearing many flowers and the last-made bulb is not of a good size, 

 it may even cause so much shrivelling as to kill the plant, the 

 bulbs being unable to again recoup themselves. It becomes 

 obvious, therefore, to every cultivator that it is far safer, if the plant 

 is not to be injured, to cut away all flower spikes that are not 

 supported by large bulbs. It is also very desirable that the last- 

 made bulb, even if of good size, should have been made by its own 

 plentiful root action, and not have drawn too largely on the back 

 bulbs for its sustenance. 



To grow orchids successfully, it is more than half accomplished if 

 the glass-house is a suitable one and is in a suitable position. Speak- 

 ing generally, a span roof house with the sides facing east and west 

 is the most suitable. In a lean-to house facing south or west it is 

 absolutely impossible to grow the cooler orchids successfully, because 

 it is necessary to heavily shade the house from the burning summer 

 sun and in so doing the light is sacrificed. A lean-to house with a 

 cool aspect, say north or east, is quite suitable for such plants as 

 Odontoglossum and cool Oncidium. It is quite possible to grow orchids 

 requiring more heat and enjoying more sunlight in a house facing 

 south or west. Shading will, however, be necessary, though not to 

 so great an extent. The four things the orchid cultivator has to 

 remember are, light, air, moisture, and temperature ; if any of these 

 is more important than another it is air. If orchids are grown that 

 require great heat it is not possible to give all the air they require, 

 and in fact the steamy forests of Guiana do not suggest air, but rather 

 the want of it ; but most of the orchids now cultivated come from 

 hilly districts where the air is constantly in motion. It is not suffi- 

 cient to have bottom ventilators and top ventilators open ; when the 

 outside conditions are suitable it is far better to open the door wide 

 at one end of the house and to shut the ventilators, so as not to 

 cause a draught, for plants are as susceptible as human beings to 

 draughts. With regard to light, give all the light possible without 

 the direct rays of the sun, except from October to the end of 

 February, when the glass should be kept as clear as possible to admit 

 the maximum amount of light. The amount of moisture in the 

 house is an important matter. It is, however, quite a mistake to 

 suppose that the house wants damping three or four times a day. 

 If an understaging is provided of some porous substance, such as 

 brick ballast or broken coke, the former for preference, a large amount 

 of moisture will be retained after thoroughly wetting it. In summer 

 I find that once a day is, as a rule, sufficient, unless the weather is 

 extremely dry and hot. In winter, when the plants are resting and 

 a drier air is required, sometimes once a week is all that is necessar) , 



