August 1, 1903. 
THE GARDENING WORLD 
669 
QUESTIONS AND ANSWERS. 
The Editor invites enquiries for reply in this column. These 
enquiries may cover any branch of gardening. Questions should be 
gut as briefly as possible, and written on one side of the paper only ; 
a separate sheet of paper should be used for each question. 
Readers are also invited to give their fellow gardeners the benefit 
of thevr experience by sending supplementary replies. 
Replies cannot be sent by post, even if a stamped, addressed 
envelope is enclosed, and the return of specimens cannot be undertaken. 
Anonymous communications are treated in the usual editorial manner. 
Address letters: The Editor, “The Gardening World,” 37 and 
38, Shoe Lane, London, E.C. 
Potato Stems Not Growing. (G. M.) 
During the last two years we have heard a good deal about 
Potatos either not throwing up .their stems, or if they do grow 
they make very weak growth. What is the precise nature or 
cause of this behaviour is not very clear ; in fact, many corre¬ 
spondents have complained of the same thing, but no one, so 
far as we know, has been able to give any definite or precise 
answer so that the matter can be remedied. Some authorities 
on the subject state that the Potatos were over-matured before 
being lifted in the previous summer or autumn, and that greater 
success would follow if the tubers were lifted before they become 
dead ripe. We are very doubtful whether this will explain the 
peculiar behaviour of Potatos in this respect. We think that 
something yet remains to be discovered. It very often happens 
that Potatos are weakened before being planted out by the 
sprouts getting broken off in the operation of planting, even if 
they are not pulled off intentionally. Would it be possible 
that your sets were allowed to become partly dried up before 
being put out in spring, and then put into dry soil ? We have 
seen Potatos, however, treated in this way, but did not notice 
that they behaved in the manner you mention. We think that 
a good deal depends upon the seed, and we should advise you 
to use the varieties that have hitherto given you most satis¬ 
faction until the mystery becomes cleared up. 
Orchid Seeds. (J. L. Cassels and Co.) 
We cannot tell you where 1 you are likely to get Orchid seeds 
to buy, for as far as we are aware they are not raised with the 
object of selling the seeds, but of raising plants from them. 
Usually those who save seed gather that which results from the 
crossing of two different species or varieties, with the object of 
getting something new. A considerable amount of interest is 
vested in these artificially-crossed species, because there is 
always a certain amount of uncertainty as to the value of the 
progeny so raised. The hybridists then desire in most cases 
to germinate and flower their own seedlings, with the view of 
testing their value before they put them into commerce. 
A large percentage of the raisers of seed are amateurs. You 
might, however, try Messrs. James Veitch and Sons, Ltd., 
Chelsea, London, and Messrs. Oharlesworth and Co., Heaton, 
Bradford. We may as well point out that seeds either of wild 
plants or cultivated ones are not an article of commerce, because 
those who grow Orchids would rather have the wild plants 
introduced than go to the trouble of raising them from seed. 
Grubs in Fern Fronds. (J. Fitt.) 
The specimens of grubs you sent could not be identified 
beyond the fact that they were the larvae of some of the saw- 
flies, but it could not be determined to what genus or species 
tlle .y belonged. If you could obtain some of the perfect insects 
and send them enclosed in a box we shall try and ascertain for 
you the name of the creatures. The best means of destroying 
the insect would be to bum the infected fronds, and thereby 
prevent the grabs from going through their metamorphosis and 
laving eggs upon other plants. You could also catch the four- 
winged flies if you find them hovering about amongst the Ferns. 
Ihey are not very rapid in their movements, and you would be 
'? e ca tch them with a butterfly net. They are flies with 
tour wings and rather flattened bodies. 
Vinery Attacked with Bed Spider. (Red Spider.) 
If your vinery is heated with hot water we should advise yo 
to make a thin paste or paint with flowers of sulphur and watei 
and paint the hot water pipes. Then for the purpose of creatin 
a slight fume of sulphur in the atmosphere of the house yo 
should Tight the fire and heat the water in the pipes gently, so a 
to diffuse the effect of the sulphur through the house. This 
might be done in the afternoon when closing the vinery, and if 
there are still some spiders remaining the operation might be re 
peated a second time. As a rule the red spider very soon suc¬ 
cumbs to this form of treatment. There would be no necessity 
for syringing or wetting the atmosphere of the house in any 
way. We must warn you, however, that if your house is heated 
with a flue that sulphur must not be used upon the same, 
because if it gets in any way overheated the sulphur might burn 
and give off strong fumes that would destroy the foliage of the 
vines. 
Sowing Winter Onions. (J. McK.) 
We should say that the third or fourth week in August would 
be a good time in your district for sowing Onions to stand the 
winter. It is not necessary that they should attain a large size 
before winter, but they should at least be well established and 
have taken, good hold of the ground to prevent their being thrown 
out by frost. If your district is warm and mild you might sow 
ten days r r a fortnight later than that time. In sowing winter 
Onions one of the most important points to observe is to sow in 
a. fully exposed position, so that the Onions may derive the 
benefit of exposure to light and air. They must be right away 
from trees and from walls that would shelter them in any way, 
so that they may get sturdy and hardy before the approach of 
winter. In this neighbourhood cultivators often sow somewhat 
later, as the climate is milder and the Onions commence growing 
much sooner in spring. 
Pears not Setting their Fruits. (M. M'Laren.) 
It is a fact that some Pear trees, and likewise some Apple 
trees, do not set fruits when confined to their own pollen. As 
far as we are aware, however, no experiments have been con¬ 
ducted in this country, and not many observations have been 
made and recorded upon the subject. The professors at Cornell 
University Experiment Station, Ithaca, U.S.A., have written a 
fair-sized book on the subject, but the varieties upon which they 
would make experiments would in most cases be different from 
European Pears, and their experiments would hardly be likely 
to help you except by furnishing you with a hint or two, which 
you might put into practice for yourself. With your indoor 
Apples and Pears, when they axe in bloom it would be worth 
your while^ to grow several varieties and fertilise the flowers 
artificially by taking the pollen from one and applying to another 
by means of a camel s hair brush. If you record the cases, and 
what varieties you used, you could then get a guide as to those 
which give the best results on future occasions. If you have any 
bees it might be worth your while to move a hive indoors while the 
trees are in bloom, otherwise you will have to make the experi¬ 
ment as. we suggest. 
Rare and Common Shrubs. (A. V. M.) 
None of the flowers you sent up are very rare in the south 
of England, but we feel quite certain that some of them would be 
laie in youi district, on account of the much more northern 
latitude. We have seen them, however, in Scotland, much 
fuithei noith than your district, but we had a similar expe¬ 
rience to you, in the shrubs being of slow growth and in their 
refusing to flower. We shall refer to them by name, and by 
refeience to the names of plants you will fined your numbers 
Kalmia angustifolia is always of slow growth and dwarf in 
habit, but if grown in a peaty soil, it ought to flower freely with 
you. Both the Spiraeas you sent should grow very success¬ 
fully with you; in fact, the typical form of S. salicifolia is 
naturalised in some places. Piptantkus requires the shelter 
of a wall, even in the south, to flower freely and stand the 
winter. Pernettya flowers freely much further north, but does 
not always fruit. Cassinia fulvida would be rather tender in 
the north. Kalmia latifolia will grow even in the far north 
but seldom flowers. We presume the wood does not ripen pro¬ 
perly. It flowers freely in the vicinity of London. On the 
whole, then, Piptanthus, Cassinia, and Kalmia latifolia would 
be the least common, and least likely to give full satisfaction 
in your district. 
Brown Aphis on Peaches. (P. C.) 
At this season of the year the aphides are mostly confined 
to the growing tips of the young shoots, while the tips'are youn* 
and tender, and also afford shelter by being partly closed up? 
The area over which they are distributed is, however, limited, 
and you could not do better than syringe the trees in order to 
damp the foliage, and then dust them with tobacco powder 
It is quite unnecessary to dust all the leaves ; in fact, it is only 
