224 
AMERICAN AGRICULTURIST. 
[June, 
gentlemen have got bold of a practice that 
has been tried and abandoned many times botli 
here and in Europe. The failure is due to the 
obvious fact that the soil surrounding the hot- 
air flues abstracts the heat below and laterally, 
■while it is only wanted above, hence the heat 
abstracted from the flue except by the soil 
laying over it, is, to a great extent, lost. So 
well are we aware of this fact that in heating 
our green-houses by hot water pipes or by smoke 
flues, we are always careful to elevate them at 
least six inches above the ground, to prevent the 
loss of heat by the absorption of the soil below. 
In the past dozen years, plan after plan for ar- 
tificially heating pits and green-houses have been 
advocated, tried and abandoned by us, just as 
they had been advanced and abandoned by those 
who had preceded us ; such will be the fate of 
those " fire hot-beds." Those of us who have 
had nearly a quarter of a century's experience 
among the hundreds of green-house establish- 
ments in the vicinity of New York, have tried 
or have seen tried, the running of flues under- 
ground, to our cost and sorrow ; and have long 
ago come to the conclusion that if a hot-bed 
proper is to be used at all, it must be made of 
some such material as horse manure, leaves, tan- 
bark, or refuse hops. Hot-beds for commercial 
purposes are rapidly being abandoned, and the 
popular low ridge and furrow green-house, 
heated by smoke flues or hot water pipes, is in 
use wherever the expense can be spared. The 
convenience and satisfaction attending the work- 
ing of these green-houses, compared with the 
hot-bed, are manifest. We can get inside and be 
at work in all weathers, so that our labor is just 
as valuable in a stormy day as in a fair one, and 
the plants are always right under the eye. 
plants, when growing, need an abundant supply 
of water ; but the pot should be so drained that 
none will remain stagnant about the roots. 
After flowering, the water should be gradually 
The Scarlet Crassula. 
"While we take a pleasure m welcoming all 
such new plants as the Bouvardia, described in 
another article, we have an equal satisfaction in 
calling attention to old and meritorious ones — 
excellent things which are thrust aside to make 
place for new comers, and with few to say a 
word in their favor. One of the first green-house 
plants that the writer learned the 
name of was the Scarlet Crassula 
(Crassula coccinea) — though the 
old gardener did call it with a 
very broad Scotch accent " Crad- 
july Cockseeny." Though for a 
long time a popular plant, and 
even now a leading one with the 
London flower dealers, we can- 
not learn that it has ever receiv- 
ed a popular name. It is now 
placed by botanists in the ge- 
nus Rochea, and its former botan- 
ical name, Crassula, may as well 
be adopted as the common one. 
It belongs to the same family 
with the Stone Crops (Bedims) 
and House-leeks (Sempervivums), 
and like them has fleshy leaves 
and a great amount of vital- 
ity. Its leaves are arranged in 
four rows upon the stem, which 
bears upon its summit a cluster 
of scarlet flowers of about the 
size of those in the engraving. 
It is propagated from cuttings 
which are laid aside to dry for 
a few days before they are pot- 
ted — a precaution necessary with succulent 
plants to prevent them from decaying. The 
the scaelet ckassdla. — (Sochea coccinea.) 
withheld, and the plants should have a season of 
rest and dryness. The Crassula is well suited to 
house culture, as it endures a dry atmosphere ; 
but it is easily injured by frost. Two others be- 
MAZE AT CENTKAL PAKE. 
longing to the same genus, RocJiea falcata and 
B. perfoliala are interesting green-house plants. 
The Maze at Central Park. 
In the gardening of a century or two ago, the 
Maze or Labyrinth was considered an essential 
appendage to grounds laid out in the then pre- 
vailing style. The Maze is a tortuous, intricate 
path, bordered on each side by a hedge. If in- 
geniously arranged it affords an amusing puzzle 
to reach the center, where there is usually a 
shaded seat or a flue view to reward the suc- 
cessful visitor. In the present style of land- 
scape gardening the Maze is considered as too 
artificial, and it is mainly a thing of the past. 
At the New York Central Park one has been 
constructed by the efficient gardener, Mr. I. A. 
Pilat, and here, where the object is to furnish as 
much variety and amusement as possible, it 
comes in appropriately enough. The hedges 
may be of Norway Spruce; in England the Yew 
is a favorite plant for the purpose. The hedges 
are kept about five feet high, or they may 
be so tall that they cannot be seen over. In the 
labyrinth at the Park there is a commodious 
rustic shelter, A, at the center ; at B, are rustic 
seats, and at C, circular seats around shade 
trees. The Maze is situated east of the old 
Croton reservoir, not far from 79th Street. 
Pruning Evergreens. — We are frequently 
in the receipt of letters asking how and 
when to prune evergreens ; but each writer for- 
gets the important point, — what he wishes to 
prune for, or whether he is growing a forest for 
spars, or a low hemlock hedge. Many ever- 
greens, if they grow as single specimens, will 
take on a form which no art can improve. Spec- 
imen trees will need but little pruning ; if the 
upper limbs are disposed to overhang the lower 
ones they should be shortened, to give those be- 
low them a fair share of light and air. This may 
be done while the young growth is yet tender, 
if a mere cutting back is all that is required. If 
limbs need to be taken out, it may be done late 
in autumn or early in spring. Hedges in their 
early growth are cut in autumn after the sea- 
son's wood has ripened ; but when the plants 
have become well established, and it is desired 
to check the growth, they are cut back in June 
while the young shoots are still 
immature. Pruning at this time 
lias the same dwarfing effect 
that pinching has upon a de- 
ciduous tree. A very little trim- 
ming may afterwards be needed 
in early autumn to bring the 
hedge into the desired shape. 
Seeds op Perennials. — One 
great obstacle to the cultivation 
of herbaceous perennial plants, 
is the difficulty with which the 
seeds of many germinate. A 
large proportion of them re- 
quire to be sown as soon as 
ripe ; they come up soon and 
make strong plants, which will 
bloom next year ; while if kept 
until the following spring, they 
would remain a full year be- 
fore they came up. Several of 
the Columbines behave in this 
manner. We notice in the seed 
catalogue of Mr. Ortgies, of 
Zurich, Switzerland, that those 
seeds requiring to be sown in 
summer are indicated. This is 
very useful information, which our dealers 
would do well to give in their catalogues also. 
