: 
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B. 
1900 SUPPLEMENT—RECENT INTRODUCTIONS, &C. 73 
Aquatic Plants—continued. 
judicious disposition of the plants according to their 
individual characteristics, more particularly with respect to 
their habit of growth. For instance, there are those kinds 
whose leaves float on the surface of the water, amongst 
which are included the beautiful Water Lilies and the 
Sweet-scented Water Hawthorn; whereas other kinds 
assume a more or less tall and erect habit, as, for instance, 
the Flowering Rush and the Bog Bean. Then there are 
those the foliage of which is entirely submerged, but 
which produce their flower-scapes above the surface 
of the water, such as the pretty Water Violet, the 
Water Soldier (Stratiotes aloides), and the interesting 
Bladderworts, besides numerous other equally desirable 
and pretty subjects that thrive luxnriantly at the water's 
edge, where their roots can revel in an abundance of 
moisture. 
The most suitable time for planting hardy Aquatics is 
about the beginning of April, or as soon as they commence 
active growth. Of course it may be desirable afterwards to 
introduce a few new acquisitions, to fill up spaces where 
plants may have failed, or to introduce a few tender kinds 
during the summer months which require the protection 
of a greenhouse during the winter; but for general 
planting, the time stated above is invariably the most 
_ advantageous. In ponds, the groups—more especially those 
with floating leaves—should be separated from each other 
by clear open spaces of water, so that when in full growth 
their beauty will be better displayed, and the surface will 
not present the appearance of being too much covered with 
foliage, which would have a decidedly monotonous effect. 
So much for the hardy section. Now for the tropical and 
tender plants. Everyone who has viewed a representative 
collection of tropical and tender Aquatic Plants must have 
admired the great diversity of their appearance and, in 
many instances, the contrasts they present to the more 
familiar ones of temperate or northerly latitudes. 
Forming, as they do, a class of plants requiring conditions 
resembling, as nearly as possible, those in which they are 
found thriving in their native habitats, their cultivation in 
this country has necessarily been limited to some of the 
principal establishments where these conditions have been 
afforded, and they then have gained for their enterprising 
owners the genuine appreciation of horticulturists. 
In the construction of a house for the cultivation of 
tropical Nymphas and other Aquatics, the span-roofed 
form is the most suitable to adopt, as this admits the 
greatest amount of light, which is a most essential condi- 
tion in their successful cultivation. The roof should not 
be too lofty—this is also an important point in con- 
nection with the conditions to be observed in their treat- 
ment. As no shading will be required it is all the more 
necessary that the house should be glazed with good clear 
glass, as oftentimes, through the presence of air-bubbles in 
the glass, which focus the sun’s rays, heat is conducted - 
which scorches holes in the leaves, and thereby disfigures 
the plants. Ventilation should be amply provided, both in 
the sides of the house and in the roof, for Aquatics 
generally, and Nymphzas in particular, when in full growth, 
require abundance of air on hot, sunny days. Around the 
inside of the house, abutting on the walls, benches or 
borders may be formed for the accommodation of orna- 
mental plants, or small tanks or beds may be constructed 
for the culture of Aquatics, or moisture-loving plants. For 
heating the house, sufficient pipes should be introduced 
to ensure a minimum temperature of from 65deg. to 70deg. 
Fahr., and this would afford means for maintaining a higher 
temperature when desired, and would minimise the amount 
of piping necessary to be einp!oyed for heating the tank. 
A tank for the reception of thé Aqnaties should be con- 
structed in the centre of the house, and whatever the 
desired shape may be, and whether entirely sunk in the 
ground, or partly above the ground-level, a firm foundation 
must be first secured. The bottom should be made perfectly 
Vol. V. 
Aquatic Plants—continued. 
solid with a layer of bricks well bedded in cement 
and sand, and on the top of this course a good thickness 
of stone or brick rubble concrete should be added. The 
walls may be built with either brick, concrete, or stone, 
the thickness of which will largely depend upon the size 
of the tank. If it be desired to have a tank from 20ft. 
to 30ft. in diameter and about 2ft. Gin. in depth, walls 
12in. thick to within 10in. of the top, and from that point 
sloping outwardly, with the masonry set in cement, would 
be sufficiently strong. The tank should afterwards be 
faced both inside and out with about lin. coating of 
good cement, and the surface smoothly finished off to 
make it watertight. On the inside, formed against the 
walls, a few beds, enclosed in brickwork, might be intro- 
duced for the accommodation of strong, erect-growing 
Aquatics; these should reach to about 6in. below the top 
of the tank, so as to admit of their being submerged to 
a depth of 3in. or 4in. when the water is at its normal 
height. 
For heating a tank of the dimensions given, two 4in. 
pipes (a flow and return) carried round the inside, about 
6in. from the walls and the same distance from the bottom, 
will be quite sufficient, and these should be furnished with 
valves on the outside of the tank to allow of regulating the 
temperature of the water. An air-pipe should be fitted to 
the flow-pipe at its highest point, to release any air or 
steam that may accumulate in the pipes. The tank should 
be furnished with a plentiful supply of water, and a tap 
connected with the service-pipe, so that it can be turned on 
to its full capacity when the tank requires refilling, or .- 
regulated to a gentle flow when the Aquatics are in full 
growth, or as desired. An overflow stand-pipe is also 
necessary, the top of which should reach to nearly the 
full height of the tank. If constructed in two parts, 
somewhat on the telescope principle, so that the upper 
portion can be raised or lowered by sliding or screwing into 
the bottom part, means will thus be afforded for keeping the 
water at any desired height. A large brass perforated cap, 
similar to the rose of a watering-can, should be fitted to the 
top of the overflow-pipe to prevent floating matter from 
choking it, and the escape of small Aquatics. This stand- 
pipe should be situated conveniently close to the wall: It 
should be fitted into another pipe, set level with the 
bottom of the tank and connected with the drain provided, 
so that when any operations necessitate the tank being 
emptied the stand-pipe can be removed and the water 
readily drained off. If it should be considered desirable to 
paint any part of the tank that is above the ground-level, 
it will be best to defer doing so for a time, as the new 
cement would blister the paint and cause it to peg off. 
It is not advisable to plant a new tank immediately 
after it is finished, but it may be filled with water, 
which should be allowed to stand for at least a week. 
The scum that will have by this time accumulated on 
the surface should be flushed and syringed off, and the 
tank then filled up with fresh water. 
The next important operations are the arrangement of the 
tubs or large pots in the tak, and the preparation of the 
soil in which the Aquatics are to be planted. Of course, 
brick enclosed beds may be more freely introduced where 
plenty of room is afforded for growing very large speci- 
mens; but in a tank of limited dimensions, where it 
is desired to grow several plants of moderate size, 
tubs or large pots will be the most suitable, as these 
have the advantage of being readily moved. If tubs 
are employed—and perhaps they are preferable for an 
indoor tank—a very useful size will be found in those 
measuring about 18in. square, and the same in depth, 
with the angles securely dovetailed. They are best 
made of well-seasoned lin. elm boards, as this wood is 
very durable when submerged in water. Z 
The Nymphza family is represented by so many species 
and varieties of decided merit that they should occupy a 
: ae 
