156 THE GREEN-HOUSE. [Feb. 
But be very particular not to admit sharp or cutting winds, or 
frosty air, into the green-house at this season | to avoid which, you 
must never be absent while the windows are more or less open : 
for the changes of weather are so sudden, that a few hours inatten- 
tion might do irreparable injury to your plants, especially to the 
more tender kinds. The safest method now of admitting air, is by 
sliding down the upper tier of your front windows, less or more, 
according to the weather, which will not only admit the fresh, but 
discharge any foul air which has been generated in the house. 
In frosty weather, keep your lights all close, and if very severe, 
defend the windows at night. If you have roof-lights, protect them 
as directed in January^ page 87. 
Fires may also occasionally be used, and indeed are indispensa- 
ble at times^ but these ought never to be resorted to except when 
absolutely necessary, either to keep out the frost or to dispel dampsj 
and even then you are to be very cautious not to create thereby too 
strong a heat in the house, never above 40 or 45° of Fahrenheit's 
thermometerj for this would cause your plants to push and get into 
a fresh state of vegetation, which would be extremely injurious to 
them during any of the winter months. 
Another thing to be regarded, is to keep the plants of all kinds 
free from casual decayed shoots and leaves, for those are not only 
hurtful to the plants while in the house, but appear very unsightly} 
therefore, whenever such appear, let them be constantly taken offj 
keep also the pots, &c. and green-house always neatly clean. 
The latter end of this, or any time next month, you ought to 
loosen the earth in the top of the pots or tubs of your oranges, 
lemons, and other plants in general, and take out about an inch deep 
or more, adding some fresh in its stead; this will prove very bene- 
ficial to the plants, and whoever will bestow this little dressing 
upon them, will see the advantage of it in a short time. 
Your pots of Cape bulbs, such as Ixias, Gladioluses, Lachenalias, 
Moreas, Watsonias, Lapeyrousias, Walchendorfias, Tritonias, An- 
tholizas, Cyanelias, and Oxalis versicolor — Babianas, Massonias, 
Geissorhizas, Melanthiums and Melasphserulas, &c., which are 
now in a state of vegetation, should be kept all towards the front 
of the house, and as near the glasses as possible, lest they should 
draw up weakly, and thereby produce but indifferent flowers. 
Hot-beds for raising Green-house Plants. 
Make hot-beds to sow tender exotic seeds in, observing to work 
the dung well, turning it over two or three times while it remains 
in the heap, at intervals of four or five days; make the beds as 
directed for cucumbers, page 12, to the height of three feet six 
inches; put on your frames, and lay eight or ten inches of good 
fresh tan even over the bed; if that cannot be conveniently had, 
lay on six inches of dry earth; when the bed comes to its heat, sow 
your seeds separately in pots, and plunge them into the tan or earth; 
some of these will not vegetate for a long time, and others frequently, 
lie in the ground a whole year. When the heat of the bed is on the 
