AIR IN GREEN-HOUSE?. 
127 
them in a dry, cool frame, planting them out 
among rockwork in the spring, or, if preferred, 
blooming them as pot alpine plants. The plant 
is easily increased by the small off-shoots pro- 
duced from it when in a growing state, or by 
seeds. 
The Primulas are the type of a natural 
order of plants, — Primulacea? ; and in the 
Linnasan arrangement, they belong to Pent- 
andria monogynia. A collection of the dif- 
ferent species of Primula forms an exceed- 
ingly neat and interesting group. 
GERANIUMS AND OTHER GREEN-HOUSE 
PLANTS. 
There is not a plant that is worse managed 
than the Geranium in private establishments. 
It is allowed to grow its own way, and gene- 
rally to get bare on the lower part of the 
stems, and lanky and gauky all over. Year 
after year the plant is permitted to stretch its 
limbs whichever way it is inclined to grow, 
and there is scarcely a set of more uncouth 
objects than the plants in most private green- 
houses. The secret of all this is, that private 
growers are afraid of the knife, whereas they 
can hardly use it too much ; but when the 
plant has once assumed this straggling ugly 
form, it is difficult to do much for it : for, 
generally speaking, it has no eyes to break if 
it is cut clown, and this arises from a species 
of cleverness which is very destructive to the 
beauty of an old plant. Many lady gardeners, 
who tend their own green-houses, are bent 
upon taking off slips, either to increase their 
stock or to give to their friends, and they 
fairly go to work at the wrong end. A nice 
shoot or two comes out at the lower part of 
the stems. They boast they have some nice 
slips coming ; and as soon as they are large 
enough to come off, they merely break them 
out close to the stem, and make new plants. 
Now this is destroying that part of their best 
plants which most requires the new branches 
to furnish them well at the bottom, and it 
actually strengthens the rambling growth, 
which it should be the object to check. To 
this habit, which is cetainly not so general as 
it used to be, but is still very prevalent, may 
be attributed the ugly growth of most green- 
house plants, as well as geraniums, and the 
constantly breaking off of these under-slips 
renders the stem so barren of eyes as to make 
it doubtful if they would break out, if the 
plants were cut clown. But private persons, 
and particularly lady gardeners, are also afraid 
of renewing their plants, instead of depending 
on old ones; and this prevails through almost all 
their garden stock, whereas nearly every thing 
they grow would be the better for renew- 
ing ; and it is absolutely necessary in most 
subjects to renew them annually, whenever 
young plants grow and bloom better than old 
ones ; and this is the case with very many 
plants. But supposing we really want large 
plants, they should only be allowed to grow in 
the most handsome form. Every luxuriant 
branch should be checked before it grows too 
far out. Not a leaf should be taken off the 
lower part of a plant ; for bare stems, which 
can never afterwards be properly furnished, 
are the certain consequences of this too gene- 
ral practice of breaking off the lower side 
shoots to make new plants. Reverse the prac- 
tice ; take the slips from the top, and leave 
every thing on the lower part, and we pro- 
mote bushy growth, and secure handsome 
plants, however old they may be. 
TREATMENT OF BARE-STEMMED PLANTS. 
The best mode of making plants sightly 
that have become bare at the bottom, is to turn 
them into standards. Select the best among the 
stems, of which, perhaps, there are several, and 
cut the rest away. You must have regard to two 
or three points of importance : first, it ought 
to be a stem that carries the largest quantity 
of well-shaped head ; for this purpose, remove 
the rest on one side by the hand, and hold 
them away from the one you propose to re- 
tain, and trying the best of them one at a time, 
you make your election by choosing that which 
has the best head ; when you have convinced 
yourself which this should be, cut away the 
others close to the pot, and to the old wood ; 
put a stake in the pot, quite upright, to fasten 
the stem to, that it may be made to grow per- 
pendicularly. Cut in all the rambling branches 
of the head, that it may break out in other 
placesandbecomemorebushy. There will gene- 
rally be a vigorous growth in consequence of 
the cutting in of so much of the plant, and this 
hastens the increase of the head ; but as soon 
as the shoots are strong, those which are 
pushing too fast for the rest should have their 
ends pinched off, for otherwise they would take 
the lead, and cramp the growth of all the rest. 
Whatever shoots then come out down the stem 
should be rubbed off, unless they come so thick 
all the way down as to justify the forming of 
a bush once more ; all partial buds, however, 
and they are mostly very much so, should lie 
rubbed off, that the whole strength may go 
into the head. By this means handsome 
standards may be made of very ugly bare- 
stemmed bushes. 
AIR IN GREEN-HOUSES. 
The circulation of air is one of the most 
important provisions in all kinds of horticul- 
tural buildings, nothing but that will fairly 
