June U, 1913- 
THE GARDENERS’ MAGAZINE. 
443 
the green leaf. 
In the course of an admirable lan^rn lec¬ 
ture delivered before the North of Engla^ 
Sk)cietv at Leeds, last month, 
B.s.., told his 
audience that recent years have seen seve- 
ral attempts made to utilise the sun s rays 
Hireciv for the production of steam power, 
but it IS not always realised that every g^n 
leaf represents a successful attempt to har¬ 
ness the sun’s rays in the service of manu¬ 
facture, and with the energy so obtained the 
leaf is busy in daylight building up foods 
such as sugar and starch. We therefore in¬ 
directly utilise the sun’s rays every time we 
eat a green leaf, and so add this stored 
energy to our own supply. ^ ^ 
The sugar-beet industry, for instance, is 
an attempt, by the aid of the beet leaf, to 
utilise the sun’s rays to build up sugar for 
our use, and if in this country we are to 
compete with the tropical factory, which 
places its sugar-making agent, the sugar¬ 
cane leaf, under the more ardent tropical 
sunlight, then it will probably only be done 
by careful attention to subsidiary industries, 
such as for instance the commercial culture 
of yeast, which group themselves around the 
chik product, the sugar-beet. 
It can easily be seen that the flat green 
leaf, as it spreads itself out into the sunlight, 
is an effective trap for its rays, and by 
means of pigments it absorbs and utilises the 
red and blue rays. These, and perhaps espe¬ 
cially the red, can easily be shown bv experi¬ 
ment to be of great utility to the plant. 
Another possibility is thus opened up. Dur¬ 
ing the darker months of the year, a darkness 
often enhanced by fog and mist in this damp 
island, could not something be done by 
means of artificial light to encourage the 
growth, especially of our indoor plants? 
Siemens tried this many years ago, and 
recently Miss Dudgeon, at Dumfries, has ob¬ 
tained interesting results along these lines. 
Using the CPoper - Hewitt lamp, with 
its bluish light, she has obtained as¬ 
tonishing growth in many plants. They 
often showed a tendency to run too 
much to foliage, but this winter she has been 
able to check this largely by the use of a 
giving a greater proportion of red 
This light, thus utilised by the plant, is 
turned to account in its task of building up 
sugars and starch within the plant, sub¬ 
stances which are subsequrntly used in many 
ways within its tissues. ^ 
The great use of sugar to the plant lies in 
the fact that all the energy that went to its 
making can be obtained from it again if it 
w more broken down, and by doing this in 
the process of respiration, the plant can set 
tree heat, as is shown often in the warm 
yemperature of a flower bud or of germinat¬ 
ing seeds. 
stored in the plant, in the 
P <ducts that it makes with the aid of sun- 
iffht. is utilis^ by us in many ways. In- 
ustrial Leeds is now living and working with 
generations of 
p ants, and retained for us in the seams of 
eoal beneath our feet. 
e also at our meal tables, either directly 
vegetarians, or more indirectly, though 
tlS fhink more appetisingly, through 
he medium of a vegetarian anii^al, are draV 
g upon these stores of prisoned sunlight. 
Meyendorfi.— Like 
bromeliads, the long strap- 
^^aves of this species, arranged in a 
ci^fJ manner, go to form a de¬ 
in <irnamental plant. Just now it is 
tive and in this stage is very attrac- 
eelv^ u however, the flowers them- 
the ^ surroundings which form 
korne^ feature. The flowers are 
of tli^TTi short, very little is seen 
^hich "aro eentral leaves, however, 
fke outsido*^^^^^^- those borne around 
period A ' ^^aire during the flowering 
a good scarlet colour,, which renders 
and attrartf**'* Nidularium a bright 
“‘tractive occupant of the stove.-K. 
ORCHIDS: THEIR 
POPULARITY AND CULTURE. 
(Continued from page 365.) 
Taking into consideration the nature and 
general character of orchids, especially the 
’epiphytal species, one does not wonder that 
to master the essentials of their successful 
cultivation a longer time is required than is 
the case of other plants. By this I mean that 
growers fail to recognise the treatment ne¬ 
cessary to enable them to keep their plants in 
a thriving state for an indelintie period. It 
does not require more than an ordinary ac¬ 
quaintance with orchids to see by the cha¬ 
racter of their growth that Nature has made 
a special provision for their continual exis¬ 
tence. In the bulbous kinds, such as catt- 
leyas, laelias, dendrobiums, odontoglossums, 
oncidiums, lycastes, and others, the roots 
which nourish the plant are confined to the 
newly-made pseudo-bulbs, while the roots of 
the old back bulbs die after a lapse of time, 
but the better the cultivation the slower 
the decay. The advancing growth, however, 
suffers in no way by the death of these roots, 
providing the old pseudo-bulbs are removed, 
tor if allowed to remain they have to be 
.supported by the newer growth, which na¬ 
turally very seriously hinders the young 
bulb’s formation and maturation. It is in 
this renewing of the tenure of life that or¬ 
chids differ from other plants. The remov¬ 
ing of the old psendo-bnlhs should be done 
during the process of repotting, cutting them 
away from the last three or four leading 
ones; any that are removed from rare and 
valuable kinds, will, providing the eyes are 
sound, eventually start into growth, and, in 
due time, valuable stock is secured from 
material which, had it been allowed to re¬ 
main, would only have been detrimental to 
the parent plant. 
In the bulbless kinds, vandas, aerides, 
angreaecums, saccolabiums, and phalaenopsis, 
for example’ the natural provision for their 
existence is equally apparent; the lower part 
of the stems after the leaves and roots they 
produced are decayed, dies gradually up¬ 
wards, but the upper part is quite indepen¬ 
dent of the dead portion below, which has 
simply to be removed to enable the plant and 
its source of nourishment to be again brought 
into contact. This renewal of its existence is 
a peculiarity of this type of plant. In evi¬ 
dence of this I may say there are at the 
present time plants of vanda, aerides, and 
other distichous-leaved kinds m the M es- 
tonbirt collection that have been growing 
there for over fifty years. 
It is impossible to lay down any rulers 
the best for the culture of orchids. The 
plants are often found thriving under such 
verv opposite treatment,, and as one cannot 
be certain that the conditions and surround- 
ings are in all cases precisely similar, much 
more can be done by suggestion than by 
definite advice. I will, however, venture to 
sav that observation and common sense are 
very important factors if combined with a 
sys4m ^ culture the nearest approach to 
Nature, which must he the best, and will 
most probably lead to satisfactory results m 
the g^wing and flowering of . these plants. 
The cause of failure, in not a few instancy 
that come under my notice, is trac^hle to 
keeping too high a temperature. Nothing is 
more injurious to the plants, and 
would be far better m cooler quarters than 
are often allowed. A yery important matto 
is to see that a lower temperature is kept 
at night than in the day, for nothing is more 
injurious to plant life than high tempera¬ 
ture at night, nor is anything more con¬ 
trary to natural conditions. So sensitive 
are Ill plants, and especiaUy ^^^jhids to aL 
mosphenc influence, that no matter how well 
they^ are treated in other ways, they cannot 
long continue in a satisfactory condition of 
cultivation unless a proper atmosphe^ is 
maintained about them. Orchids, with few 
exceptions do not mind, hut thoroughly en- 
joy, sun heat, if moisture and pr are abun¬ 
dant, so long as they can obtain cool night 
air for recuperation after the heat of the 
day. The state of the atmosphere is without 
doubt of equal, if not more, impoiTance, than 
the potting compost for the plants to root 
in—a condition that not only applies to or¬ 
chids but to the majority of otlier plants. 
Light is the very life of most plants, but it 
is less under our control than any other 
factor. Possibly in no other cultural detail 
are orchids, and many other plants, so liable 
to be mismanaged as in respect to shading, 
and I would urge all young growers to make 
a special point of grasping the full value of 
this most essential element, light, for it is 
of the greatest importance, and nearly all 
plants pine for it in our dull, sunless win¬ 
ters, of which the recent one is a melancholy 
example. 
Influence of Ligrht. 
The great influence that light has upon 
orcliids will be seen in the plants grown in 
it, for not only are these more free-flower¬ 
ing, but the enduring properties of the 
blooms are greatly increased, frequently to 
the extent of lasting twice as long as others 
grown under more or less dense shade; more¬ 
over, the plants are hardier, so to speak, that 
is, they are not so susceptible to the effects 
of slight errors of treatment in otlier ways. 
In the case of those kinds that need a high 
temperature, with the ever-accompanying 
moist conditions of the atmosphere, it is 
not always possible to give them air as fr^ly 
as when growing naturally, but it is possible 
to a considerable extent to make up for this 
deficiency by giving the plants as much 
light as they will safely bear; for, with 
plants under glass, light has a similar cor¬ 
recting influence over deficiency of air to 
that which the presence of plenty of air has 
over an insufficiency of light. I suppose there 
are few engaged in orchid cultivation to¬ 
day who have not noticed during the past 
season the healthy vigour and growth of 
nearly all orchids that benefit by heat and 
sun.shine—sure evidence of how very benefi¬ 
cial was the hot weather of 1911, when dur¬ 
ing that rare and ideal summer we enjoyed 
in this country so many months of brilliant 
sunshine. I fear the season of 1912 will not 
give us such satisfactory results. 
I will not suggest tliat orchids, except just 
a few, will bear full exposure to light, but 
the aim should be to control it in keeping 
with the plants’ requirements. Shading 
should be employed to break or diffuse the 
sun’s rays, instead of totally obscuring them, 
as is so often the lule. Light, more than 
heat, is, in my opinion, most necessary to 
harden the tissues and. to give to the foliage 
that robust and finished appearance so plea¬ 
sant to the eye of all good cultivators. 
Another important requisite in the culture 
of all orchids is full and free ventilation, 
not only during the daytime but also by 
night, when it can be managed without 
creating a draught. It needs only to be o<m- 
sidered that the greater portion of orchids 
are epiphytes, growing, in their natural con¬ 
ditions, on the branches of trees and, in 
many cases, isolated positions on hill ades, 
to convince anyone that they are subject, 
in their native nome, to a circulation of air, 
therefore under cultivation they should be 
supplied with abundance of this very impor¬ 
tant element, in fact, it is absolutely neo^- 
sary for as it is with light so it is with 
air. ’ If there is any shortage in the supply 
of either of these factors the whole substance 
of the plants, leaves, bulbs, and roots, aie 
deficient in the solidity indispensable to keep 
up a healthy existence. Judicious use, there¬ 
fore, of the ventilators of the houses is 
always important at all season of the year. 
To freely ventilate the houses on hot, 
sunny days, and. to admit air only by a chink 
on dull days and by night is, to my mind, 
a most absurd practice. This close-shutting 
system, especially at night, with a view to 
keeping up a desired temperature, produces 
on plant life an amount of mischief difficult 
to calculate. I never could see the reason 
why ventilation, if so beneficial during the 
day time, should not he equally so during 
the night. Fresh air all night, with reason¬ 
able temperature, must be more conducive to 
