44 
Sept. 20th, 1884. 
THE 
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o 
Fumigating Orchids. —In my opinion the fumi¬ 
gating pot is as great an enemy to Orchids as to 
insects, and the sooner the practice of fumigating, in 
order, as it is said, to kill the insects, is discontinued 
the better it will be for the plants. This has long been 
my view of the matter, and I did not come to the 
decision hastily, but based it on the result of years of 
practice and observation. In every case I have found 
that the fumigation of Orchids, when carried out to 
that extent which alone will secure the attainment of 
its object—the killing of even a portion of the insect 
pests in the house, is always followed by some ill 
effects on the plants, which are immediately visible, 
and by much more which does not make itself evident 
until some time has elapsed. It is well known that 
it is really of no use to fumigate once, but that, in 
order to stand a reasonable chance of success the 
operation must be performed two or three afternoons 
in succession, and thus we can readily imagine that 
tender plants must necessarily be injured,, be the 
material for raising the smoke ever so good, but when 
it is caused by bad material the evil consequences are 
very great and soon make themselves evident. In 
olden times nothing but pure tobacco was used in 
fumigating, and that, no doubt, is the best and least 
harmful, but in the present day, in which the chemist 
plays such a prominent part, a number of things are 
brought forward for the purpose of fumigating— 
things composed of we know not what, but all of them 
causing more or less injury to the plants. 
The worst of it is that fumigating Orchids with any 
material, while certain to cause mischief, falls far 
short of the object for which it is intended, and fails 
to take any appreciable effect on that most dreaded 
pest, the yellow thrip, for as soon as the smoke 
begins to get dense, down far into the heart of the 
plant it goes, into narrow openings where the smoke 
cannot penetrate, leaving the less wise but less harm¬ 
ful aphides to fall victims, and quietly emerging from 
its hiding place again when the smoke clears away. 
Thus the insect on whose extermination all the 
grower’s efforts should be concentrated is free to 
continue its unsightly and harmful work. 
Many who have had to do with Orchids for any 
length of time, and have had experience in fumigating 
them, will be able to call to mind lamentable instances 
of injury to plants from that cause, and it would be 
well if they were to communicate their experience 
through these pages. I should also like to hear 
what others who may be in favour of fumigating have 
to say in defence of the practice. For my own part 
I have on several occasions seen a house of Odonto- 
glossums with the foliage blackened after fumigating 
as though they had been frozen, and I once saw 
£300 worth of 0. vexillarium reduced to the value of 
as many shillings by the same means, while on every 
occasion that I smell tobacco in an Orchid house I 
look for damage and seldom fail to find it. Some plants 
are much more easily affected by it than others, or 
show the evil consequences more quickly, among the 
most susceptible being Lycaste Skinneri, some Masde- 
vallias, Odontoglossum Roezlii, Bolleas, Pescatoreas, 
&c., and the two last have in many cases been 
chased out of our collections by the fumigating pot. 
These all show immediate injury wherever fumigating 
is done sufficiently to kill insect life, but the thick¬ 
leaved plants, such as iErides, Cattleyas, and Lffilias, 
although not seeming to be injured at the time, I have 
often found become, later on, spotted as though 
boiling water had been thrown on them, and in a 
manner which I considered could only be traced to the 
fumigating. 
Now that most growers adopt the “ pure ah and 
cool treatment” system,insects are not so bad as they 
used to be in our younger days, when we often had to 
spend the best part of two or three days over a large 
Vanda or JErides, densely covered with that close- 
sticking small brown scale, and often, notwithstanding 
all our care, left the specimen much scarred by 
their removal. Scale has decreased, but the abomin¬ 
able yellow thrip, so tenacious of life, is still 
in the ascendant and if on its extermination the 
Orchid growers efforts be centred he mil not fail to 
keep down the other insects at the same time. I 
THE GARDENING WORLD. 
say, therefore, what I have proved in practice, that 
the only safe way of keeping down all insect pests 
peculiar to Orchids, and particularly the yellow thrip, 
is by dipping the plants head downwards in a bath 
prepared with a solution of pure tobacco water (this I 
certainly prefer as the safest and most effectual) or, 
as some do, of fir-tree oil made only of half the 
strength recommended on the bottles, and mixed with 
rain-water only, or with any other dipping solution 
which the Orchid grower may fancy and which expe¬ 
rience has proved to him to be safe. This dipping 
system, apart from the freedom from danger of injuring 
the plants, should recommend itself to all in pre¬ 
ference to fumigating, as by its means the plants 
affected can be treated without putting the whole of 
them in the house under treatment because of the few 
requiring it. Dipping, therefore, and hand cleaning 
are the best means of keeping Orchids clean, and the 
beneficial effects of it, if carried out on certain small 
collections which I have seen periodically damaged by 
the fumigating pot, would be immediately visible by 
the improvement of the condition of the plants and 
their better flowering, for they cannot bloom well 
when their foliage is constantly injured. The im¬ 
proved state of things would, I am sure, repay over 
and over again any additional trouble taken. 
Dipping cannot be dispensed with wherever yellow 
thrips are found, fumigate or not, for it is the only 
means of getting rid of them. Few places are quite 
free from this insect, indeed such plants as Odonto¬ 
glossum Roezlii are seldom without them unless the 
plan adopted by some of the best growers be followed, 
and that is to dip all such plants three days in succes¬ 
sion every month as long as there are any signs of 
yellow thrips on them, and once a month afterwards 
be they ever so clean. There is no danger of injury 
to the plants by a little of the dipping (particularly of 
tobacco water) getting down to the roots, and conse¬ 
quently there is no need to place the plants on their 
sides to drain, all that is required is to immerse them 
head downwards, the hand being placed over the soil 
in the pot to keep it in its place. When thoroughly 
immersed remove it, still head downwards, give it a 
gentle shake, and replace it on the stage. The stuff 
used for the bath may be strained off when done with 
and stored in jars for use another time, if sufficient 
of it remains to make it worth while to do so. So 
stored it is always ready and of great service to use 
in sponging plants whenever the eye lights on any 
requiring it .—James O'Brien. 
— s~ - < ' 0 ‘ ~ - 
ORCHID NOTES. 
Orchids at Kew. —The following are among the 
more noteworthy of the Orchids in flower at Kew at 
the present time:—Cattleya aurea var. Dowiana, a 
beautiful variety with pale yellow segments and very 
richly coloured labellum. The latter is deep yellow 
in the centre, towards the base, with radiating lines 
of deep purple-brown, and the margin violet coloured, 
becoming very broad towards the apex, where it is 
beautifully fringed. Odontoglossum violaceum, with 
spikes 3 ft. long, and very numerous small white 
flowers, which are beautifully barred with pale violet. 
Oncidium triquetrum, a little gem, with leaves 3 in. 
long and spikes measuring 6 in., the flowers are 
marbled with rich brown on a pale ground. 0. bifrons, 
spike 4 ft. long with numerous yellow and brown 
flowers which are very sweet scented. 0. Schlimii, 
spike graceful, 3 ft. long ; flowers small, numerous, 
yellow, barred with orange-brown. Cypripedium 
Stonei: this beautiful Bornean species is amongst the 
most striking of the genus; the sepals are white 
with longitudinal brown bars, the petals measure 4 in., 
and are white with yellowish green lines and beauti¬ 
fully twisted, and the lip veined with pale purple- 
brown on a paler ground. Of the beautiful genus 
Phalfenopsis, the following may also be seen, P. 
grandiflora, P. rosea, P. Esmeralda, P. violacea and 
P. cornu-cervi.— Orchis. 
Oncidium Lanceanum. — This grand old Oncid 
is very frequently found in a condition best described 
as far from thriving, and more especially when grown 
in pots, although when properly managed it may be so 
cultivated and well too. Others again grow it on 
blocks, and creditable plants can be so grown if careful 
attention is paid to the necessary supply of water. A 
far better plan, however, and one which will give the 
best results, is to grow it in baskets, in peat and 
sphagnum in about equal proportions, with charcoal or 
crocks mixed freely through it. This will be found the 
best material for the roots, but one thing must be 
borne in mind, sour or decaying material must not be 
tolerated. While growth is in progress, careful attention 
must be paid not to allow any water to lodge in the 
young unfolding leaves, which being of a thick fleshy 
nature are very susceptible to damp if carelessly 
treated. Flowering as it does, late in the summer, or 
early in the autumn, according to the heat given, it 
causes it to be doubly valuable where orchid flowers 
are in demand. It does best in the East Indian 
house, in a position free from draughts, but yet where 
the air can pass freely round it. By this treatment I 
have had two spikes from one growth.— E. Dumper. 
Cattleya Gaskelliana. —The Cattleya bearing 
this name shows great variation in the colour of the 
lip, some being blotched with purple, whilst others are 
blotched with different shades of magenta. The 
shape of the lip too, is as diverse as its colour, some 
of them being nearly rounded at the edgings, as in 
C. Trianse, while others are as beautifully fringed, as 
the better forms of C. Mendelli. Being as yet com¬ 
paratively new, many who have not obtained it, will be 
glad to hear that it flowers freely from the young 
growths, as soon as the latter have fully completed 
their extension. Pot culture will I think be best for 
it, at least by that system, it thrives admirably with 
me.— E. Dumper. 
Cattleya Eldorado.—It is a pity this grand 
autumn flowering Orchid is not more frequently met 
with than is now the case. Unfortunately for its 
more extended culture it has the unenviable character 
of being “ miffy,” which deters many from trying it. 
The worst thing I find in it, however, is that it is 
very liable to breed mealy bug with the young growth, 
so that careful attention must be bestowed on it as 
soon as the leaves open sufficiently to disclose it, and 
so stop the further spread of this unwelcome pest; 
the bug, however, sticks well to it owing to the 
glutinous matter covering the young leaves. Basket 
culture, at the coolest end of the Cattleya house, suits 
it best, and it must only be shaded sufficiently to 
prevent the sun damaging the foliage.— E. Dumper. 
—-——- 
PLANT CULTURE IN MOSS. 
Some experiments on growing plants without earth 
have been made during the present year by Mr. W. 
Sowerby at the Royal Botanic Society’s Garden, in 
the Regent’s Park, and are thus recorded in the 
Society’s Quarterly Record : —“ The items necessary 
to sustaining vegetable vitality and growth are, 
1, light; 2, air ; 3, water. ‘ Earth ’ in its vast variety 
of forms, or the compound known under that name, is 
but an adjunct, not a necessity. . . . We placed two 
specimens of Scarlet Pelargoniums in garden pots, 
one filled with Dumesnil’s fertilized moss, and the 
other with fresh clean ordinary moss, both without 
any earth or admixture of any kind ; all the soil was 
carefully washed from the roots of the plants; they 
suffered little by the change, and after a few weeks’ 
growth there appears but little difference in the two 
plants; they both look as well and healthy, if not 
better, than those of a like kind, growing as usual in 
earth. On the 7th February, seedlings of the common 
Lupin were planted in a small pot filled with broken 
window-glass, the pieces varying in size from that of 
coarse sand to an inch square, and other seedlings of 
the same age and plant in a similar pot filled with 
boys’ stone toy marbles; in Both cases the pots were 
placed in saucers of water, the water reaching nearly 
half-an-inch upwards from the bottom of the pot; 
nothing has since been supplied except water, and at 
the present moment one of the plants in the pot of 
broken glass is in flower, and appears as if grown in 
the ordinary way. Those in the pot of marbles did 
not get on so well, and died after about two months, in 
consequence, I think, of the spherical form of the 
marbles allowing them only to touch each other by 
points, thus not holding so large an amount of water 
amongst them as the broad flat surface of the pieces 
of glass.”— Florist and Pomologist. 
