December 9, 1905. 
THE GARDENING WORLD 
bv making a cut on the under side and pushing 
this down amongst a compost of sandy and peaty 
.soil prepared for the purpose. Use a good strong 
pe»- to hold down the shoot at the point where 
(lie cutting is made. The shoot must then lie 
covered with soil for a little distance on either 
side of the cut. The layers will take one or two 
seasons to root, so that, after all, raising plants 
from seeds is the best way. 
Cutting Down Cornuses. 
Being a weekly admirer of your practical and 
useful paper, and a close follower of Mr. A. E. 
Thatcher’s remarks on hardy trees and shrubs and 
perennials, I have been reading his remarks in 
your issue dated 2nd December on cutting back 
certain shrubs in April. I note that Spiraea 
Douglasii, amongst others, should be dealt with 
in this way, but what T should like' to know is 
how to treat two Cornuses I possess, namely, 
C. alba sibirica variegata and C. alba Spaethii. 
The two varieties I have mentioned are, as you 
know, somewhat slow growing, and perhaps 
should not be dealt with in the way Mr. Thatcher 
recommends for C. sanguinea and others. (R. 
Morton. ) 
Notwithstanding the fact that these two varie¬ 
gated varieties are dwarf in habit, they may be 
pruned as recommended for C. sanguinea. When 
treated in this way, they are usually grown in 
large beds for the sake of their ornamental foliage, 
and when annually cut down in this way they 
produce strong shoots during the summer, with 
much larger leaves than if allowed to grow up 
to their natural height and produce numerous 
small shoots. You will be quite safe in cutting 
them down, therefore, if you do not object to 
their being about 2 ft. high at the end of the 
season; they may grow more if the plants are 
vigorous and the soil good. 
Temperature of a Greenhouse in Winter. 
I shall be glad if you can give me some direc¬ 
tions for regulating the temperature during the 
cold months of a small span-roofed greenhouse. 
I was told by a friend that there was a danger 
of injuring my plants if I kept it too warm. (J. S. 
Warne.) 
The temperature necessary entirely depends 
upon what you are keeping in the greenhouse, 
and whether you desire any of the plants to be 
in bloom. As a rule, a greenhouse is merely 
intended for resting plants in the winter time, 
and, that being so, it would only be necessary 
to keep up a temperature sufficiently high to 
keep the plants in health. For instance, some¬ 
times plants of tender character are placed there, 
and it would be necessary to have at least a 
temperature, of 40deg. In the case of resting 
plants of a more hardy character, it will be 
sufficient if you merely keep out frost. Except 
during frosty nights, it would be unnecessary to 
keep a fire burning at all. We know that some 
keep a fire burning every night during winter, so 
as to make sure that no frost gets in. That will 
answer well enough if you study the art of 
stoking, so a.s not to have the temperature too 
high at one time and too low at another. For 
such plants as Fuchsias, Pelargoniums, Indian 
Azaleas, and Agapanthus, a maximum tempera¬ 
ture of 40deg. would be ample, unless you have 
any particular object in view, such as starting 
them into fresh growth in spring. If it has sunk 
to 35deg. before morning, no damage will accrue 
to the plants just named. 
Plants for London Back Garden. 
I have a small back garden in the district of 
Camberwell, London. It faces south, but is, un¬ 
fortunately, surrounded by high walls, and, 
therefore, does not get much sun. What plants 
would be likely to succeed best? The soil is 
very poor. (T. Paynter.) 
The soil about Camberwell was not originally 
poor, but we presume your garden has suffered 
at the hands of the builder, like those of most 
others. In taking out sand for building pur¬ 
poses, the best soil usually gets tumbled into the 
bottom of the pit, and the coarse material is placed 
on the top. You can improve it by top-dress¬ 
ing with fresh soil once or twice a year, and by 
making a liberal use of the sweepings ol the 
streets, if you can secure the same, as it con¬ 
tains a good deal of horse dung. You must be 
satisfied with plants that will grow with little 
or no sunshine. In the case of shrubs, we 
should recommend Euanymus japonieus, green 
and variegated, also golden Privet and Aucuba. 
Dwarfer subjects or flowers may include Peri¬ 
winkle, Primrose and Polyanthus, Evening Prim¬ 
rose, London Pride, Solomon’s Seal, and Daffo¬ 
dils. You could possibly get Tulips and 
Hyacinths to bloom fairly well the first year, 
but you would require to get fresh bulbs every 
year to give a satisfactory display. 
Large Trusses of Hydrangeas. 
Last spring I bought some plants of Hydrangea 
in bloom, as I was surprised at the large size 
of the trusses they bore. Will the same plants 
blloom as well next spring? We have a con¬ 
servatory, but no fire heat. (T. Fergusson). 
It will all depend upon the treatment you gave 
them last year after they had finished flowering. 
If you desire the continuance of large flowers, 
the best plan would have been to cut off the 
flower trusses as soon as they were past their 
best, and to have watered the plants with liquid 
manure to encourage vigorous growth. The buds 
producing the trusses of flower are developed 
during the autumn, when the young shoots are 
ripening off. We doubt, however, whether the 
trusses will be so large next year. These young 
plants get special treatment by skilled nursery¬ 
men, who take off the points of strong-growing 
shoots in summer, root them, pot them off singly, 
and then feed them to get large leaves and strong 
crowns, from which big trusses will appear next 
year. 
Sweet Scented Plants, 
I propose to have a border of sweet-scented 
plants, and. later on, may build a rockery for 
them. In the meantime they will be growing, 
so that I can learn how to propagate them, and 
keep adding to their number from time to time. 
Will you name a dozen for a start? (C. Ewen.) 
A collection of the more common or strongly- 
scented, with plenty of variety, should include 
Balm, Costmary, Lemon Thyme, Common 
Thyme, Lavender, round-leaved Mint (Mentha 
rotundifolia), and its variegated variety, also 
Southernwood, woolly-leaved Thyme (Thymus 
Serpyllum lanuginosus), Rosemary, Hyssop, 
scented Verbena and Mentha Requieni if you 
can succeed in getting it. 
Edging for Borders. 
I am about to lay out a small garden with 
borders round the sides, and part gravel and part 
grass in the centre. Would you advise stone 
tiles, wood or plant* for an edging? If the latter, 
what are the best and neatest to grow? (P. T. S.) 
It would all depend upon circumstances as to 
what we should use in the garden you mention. 
If there is to be much walking or running about 
in it by the younger members of the household, 
neat tile edgings would, no doubt, be the most 
suitable. On the other hand, if you can be sure 
that the edgings will not be unduly trodden upon, 
then we should certainly use plants. These may 
be varied in character if you wish, but if you 
desire them to be uniform, we should certainly 
plant Box. Other edgings that answer the pur¬ 
pose, and are easily rectified or relaid every year 
or second year, are Sea Thrift (Armeria), London 
Pride, Daisies, Gentiana acaulis, Arabis lucida 
variegata, etc. We have selected plants that 
are not straggling in their habit of growth, but 
can readily be kept 1 in neat form. 
Orange Tree with Black Leaves. 
.What is the cause of my Orange Tree going 
like the enclosed? Is it disease, and how can 1 
eradicate it? The tree is verv unsightly. 
(E. G. N.) 
The primary cause of the leaves of Oranges 
going black is precisely the same as in the case 
of Camellias. Oranges are, however, worse than 
Camellias. The primary cause is due to scales 
which have been allowed to live on the shoots 
and leaves. The viscous secretion ejected by 
these scales falls on the surface of leaves beneath 
them and a fungus in its turn feeds u(>on the 
excrement, and in a short time makes the leave 
turn black. The remedy is to get a strong solu 
Lion of soft soap and water, and thoroughly wash 
the leaves with a sponge. If the soapy solution 
is kept warm, it will take off the black matter 
on the leaves more readily. In future, you should 
keep a sharp outlook during the whole summer, 
end never allow scales to find a footing on the 
plant. You can then, with far less difficulty, 
keep the plant clean. 
Climber-for North Wall. 
There is a bare and unbeautiful north wall 
facing my sitting-room window. The wall is 
really the back of ail out-building, and is some 
3C feet high. What could I plant against it 
that would not take long to cover the eyesore? 
(M M.) 
Many things would grow on such a wall, pro¬ 
vided it has plenty of exposure to light, even if 
not direct sunshine. We think, however, that 
Japan Ivy (Ampelopsis Yeitchi) would he the 
most interesting climber you could plant in such 
a situation. The leaves will remain small until 
the plant gains strength, after which, they will 
assume a much larger size, more or less resem¬ 
bling the Irish Ivy, but larger. The Virginia 
Creeper is a more rampant grower, but would 
take more time aud trouble to keep it in order, 
as many shoots would have to be pruned awav 
every yeat, after the wall has been fully covered. 
Both of these grow rapidly if you prepare situa¬ 
tions for them, and use some good nch soil to 
give them a start. The Irish Ivy is also weli 
adapted for such a position, and would grow 
rapidly. The foliage is less graceful and inter¬ 
esting, however, than those previously named. 
Weeping Willow. 
I understand there are several kinds of Weep 
ing Willow besides Napoleon’s Willow. Which 
do you consider the most suitable for the centre 
of a lawn 20 feet wide and 40 feet leng? (C. 
Lewis.) 
The American Weeping Willow (Salix purpurea 
pendula) is the most graceful of all the Weeping 
Willows, and of moderat-e size. You should 
secure it with a stem at least 5 feet or 6 feet high, 
so as to give plenty of room for the long droop¬ 
ing branches to acquire something of their real- 
character and beauty. It is a British Willow, 
although it bears a foreign name, and require: 
no skill in it.s culture, or any particular soil, so 
long as it remains fairly moist in summer. 
Gloxinias that Failed. 
Last summer I had a fine batch of Gloxinias 
staged under a 3 ine in a Grape house, but the 
leaves gradually became brown and the plant 
ceased to flower. Will the same tubers be of any 
use next year? (C. A. R.) 
The cause of the leaves turning brown was due 
no doubt to the presence of a small mite on the 
under side of the leaves very similar to the well- 
known red spider, but smaller and with less 
colour. It is very difficult to detect with the 
naked eye, and requires a magnifying glass. The 
tubers should be quite as good for next year’s 
work if they are not getting too old. As a rule, 
the best flowers are obtained from plants not 
more than three or four years old. Next year, 
when you observe the least trace of the leaves 
becoming discoloured on either side, you should 
prepare a strong solution of soft soap or ordinary 
soap and water. Either lay the plants carefully 
on their sides or employ someone to hold them 
while., you thoroughly syringe the under-surface 
with this soapy solution. After every part of the 
plant has thus been wetted put them back in their 
place, and damp down every available part of the 
house with water from the tank. This will have 
the effect of creating a steamy moisture in the 
atmosphere which will greatly aid you in eradi¬ 
cating the pest. It may he necessary to repeat 
the operation in a few days if you can detect any 
of the enemy present, hut usually the first opera¬ 
tion is e.Tectual. 
