544 
THE GARDENING WORLD 
April 25, 1891. 
PRIMULA OBOONICA. 
I note in your issue of April 11th that this Primula is 
said to have been crossed with P. sinensis. I have 
several times tried to effect the same cross, but without 
success, although I used the pollen of P. sinensis, and 
protected the blooms of P. obconica operated upon 
from insect agency. I know a large trade house whose 
foreman has also tried for several years to effect the 
same cross, but without success. It will, however, 
cross with some other species, and I believe that ulti¬ 
mately we shall get some good crosses from it. Some 
five years ago I obtained seeds from what I considered 
successful crosses, but from circumstances over which I 
had no control I was unable to sow the seed while it 
had any germinating power. 
It occurs to me that it is not a cross with P. sinensis 
that would be the most desirable, but that it would be 
preferable to use the pollen of some of the hardier 
species. Every grower of P. obconica knows well that 
P. obconica varies to an enormous extent. In some, 
the blooms are very thin, small and star-like, while in 
others they are large and almost circular, with each 
segment of the corolla almost overlaying each other. 
Some four or five years ago I exhibited an improved 
form at South Kensington, which was thought most 
highly of by the experts, and favourably commented 
upon by the press. 
At the present time I have several good forms of P. 
obconica, one of which has blooms almost lilac in 
colour, and very large, the leaves also being large, and 
leaf and flower stalks long. Another has almost white 
blossoms, although not so large as the last mentioned, 
but more freely produced. One plant in a 48-in. 
pot in my sitting-room has no less than thirty 
trusses of blooms, and it has been in the same room for 
two months. It looks as if it would go on blooming 
for another period of the same length. This is the 
freest form 1 have ever seen. 
Yet another recommendation of P. obconica is its 
comparative hardiness. Having a lot of plants in the 
autumn, I left some in an ordinary frame, which 
passed through the winter unharmed, though only 
protected with a mat, and are now coming into bloom 
grandly. Under similar treatment, many other things 
which I thought ought to have pulled through were 
killed by the frost. It will, I think, also make a good 
bedding plant, as last year I saw it bedded out in the 
neighbourhood of Bath, and doing well. I may add 
that seedlings from a pin-eyed flower will give both 
pin and thrum-eyed varieties, and vice versa. I several 
times kept the seeds separately to test this point, but 
with the same results always.— Con. 
-- 
GROUPS AT CHRYSANTHEMUM 
SHOWS. 
Your correspondent, “Man of Kent,” has touched upon 
what I have for some years regarded as a weak point 
in Chrysanthemum shows, namely, the too frequently 
unsatisfactory appearance of the groups staged for effect. 
I am quite willing to admit that they are about as effec¬ 
tive as amass of ill-assorted colours can be, and often as 
inartistic as any arrangement of plants can possible be ; 
and I fear must remain so as long as the present con¬ 
dition of things in the “ Mum” world continues. The 
present style of grouping is largely the outcome of the 
rage for enormous flowers, of mop-head and feather- 
duster proportions— very beautiful on the show-board, I 
grant; but that groups of plants carrying these monster 
flowers can be rendered artistic without the addition of 
some other plants I very much question. At the same 
time I opine that very beautiful and really artistic 
arrangements are quite possible made up entirely with 
plants belonging to the Chrysanthemum family, andcom- 
] rising the Japanese, show, and Pompon varieties, but 
not, I think, within the contracted limits frequently 
set apart ior these displays ; and it could only be 
from comparatively large collections thatan arrangement 
such as I should like to see put up could be furnished. 
There was at “The National” last autumn, as 
“ Man of Kent” says, some plants conspicuous for their 
dwarf growth and rich healthy foliage, the blooms 
being numerous and large, and it would be from such as 
these that the bulk of our ideal groups would be com¬ 
posed, with the addition of dwarf-grown Pompons in 
three or four shades of colour, and standards well 
grown, but not too lightly tied in- I saw some last 
autumn in a market nursery which would be admirably 
adapted for the purpose, with stems about 3 ft. in 
height, and heads 18 ins. to 24 ins. across. Having 
arranged our large-flowered plants in a bay, so 
that they gradually sloped down to the front, we 
should fill in the centre of each bay with dwarf 
Pompons, the colours of which might be mixed, with 
the exception of the front line, which should for prefe¬ 
rence consist of a good white ; and in the centre of each 
bay, riding above the Pompons, we would place one of 
the standards. In a very large group, higher and 
larger-headed standards might be used, towering above 
the large-flowered plants. 
If several growers could be induced to combine in the 
formation of a group as indicated, I believe a result 
would be achieved that would both please and startle 
not a few of those who habitually frequent the levies 
held by the queen of autumn flowers, and add much 
to the beauty and attractiveness of these displays. 
— TV. B. Glasscock, The Gardens, Shirley House, 
Croydon. 
-- 
BOTANICAL PLANTS. 
In connection with the Spring Show of the B,oyal 
Horticultural Society of Aberdeen, held in Aberdeen 
on Friday and Saturday, 10 th and 11th inst., Professor 
Trail delivered on each of the days a lecture on 
“Botanical Plants.” At the outset he referred in 
terms of commendation to the society’s rule anent the 
encouragement of the scientific study of horticulture. 
He then drew attention to the differences found among 
plants, selecting as examples the varieties in culti¬ 
vation of Carrots and Cabbages, alluding in some detail 
to the common Cabbages, Kale, Jersey Cabbages, with 
stems several feet in height, which were used as 
walking-sticks; Brussels Sprouts, Kohl Pi-abi, and 
Cauliflower, in which the flowers w r ere much modified, 
but when allowed to flower showed the same forms and 
the same kinds of fruit as common Cabbage. The 
varieties of flowers in cultivation were then dealt with, 
the Cyclamens and Auriculas being taken as examples. 
A passing reference was also made to the various forms 
of the Strawberry, the Apple, the Pear, &c. The 
difference in the structure of the plant was pointed out 
and illustrated by means of diagrams, to show in how 
far each of the chief tissues in the plants was required 
for its nourishment. Some of the varieties in culti¬ 
vation were actually prejudicial to the continuance of 
the species in cultivation, such as doubled flowers and 
seedless fruits ; but these forms were beneficial from 
man’s point of view. 
The greatest range of variation in cultivated plants 
always affected those parts on each plant directly 
useful to man. The method by which the main 
changes in plants were effected was by obeying certain 
laws of nature. We found the tendency to change on 
comparing the offspring with the parent forms. This 
tendency was increased by the effect of the surroundings, 
by the cultivation of the soil, the removal of weeds, the 
supply of manure and other food to the plant to enable 
it to take it up readily, and grow luxuriantly. The 
effect of such treatment was seen in comparing the 
results obtained by sowing seed from the same seed 
vessel. In poor soil the plant was weakly, showing 
small development of the stems and leaves, while the 
flowers were often comparatively of large size ; while in 
rich soil, with abundance of food supplied to it, and the 
weeds removed, the roots, stem, and leaves developed 
largely, while the flowers were often smaller or might 
almost be wanting. 
Then, along with this law of tendency'to change, 
we had to take the law of inheritance, by which the 
offspring tended to reproduce the peculiar forms of the 
parent where these develop from the [ordinary parent 
species. By careful selection of the varieties we found 
the law of inheritance tended to establish a variation in 
form from the ordinary type ; and it was by employing 
these two tendencies to change in certain respects while 
inheriting the peculiar changes that the diversity of 
flowers in cultivation had been brought about, and 
perpetuated by carefully keeping up the conditions that 
had first brought them into existence. Professor Trail 
was cordiaily thanked at the close of his lectures, 
and Mrs. Trail was presented by the society with a 
magnificent bouquet. 
-- 
CROWDED SHRUBBERIES. 
Crowded plantations and shrubberies are far too 
common, there being but few districts whSre they are 
not to be met with. By far'the majority of private 
grounds are laid out and planted either by landscape 
gardeners or by nurserymen, or it may be both have a 
hand in the matter. What they have to study is how 
best to create an immediate effect, at the same time 
arranging the trees and shrubs, deciduous and ever¬ 
green, so that the best of everything should ultimately 
be left in sole possession. The latter being distributed 
accordingly—that is to sayq with due regard to their 
habit of growth—all intervening spaces are filled in 
with what may be termed supernumeraries, as dis¬ 
tinguished from those permanently planted. In many 
cases, or where carte blanche is given to the planters, 
comparatively thick planting is practised, the 
shrubberies having a well-filled appearance at the 
outset; and the ground being trenched and otherwise 
well prepared, the growth of the majority of trees and 
shrubs is rapid in consequence. Before, however, the 
commoner and more vigorous occupants of these newly 
formed shrubberies overrun, impoverish, and literally 
spoil the choicer and more delicate subjects, the 
thinning out ought to commence, leaving only those 
originally intended to be permanent. In how many 
instances is this judicious thinning carried out? 
What is the present state of thousands of shrubberies 
and plantations ? Chaos is the word that really most 
correctly describes it. The more robust subjects do 
certainly manage to hold their own, but even these 
would have been far more handsome and valuable had 
they not been obliged to struggle for the supremacy. 
There are two ways of getting over this difficulty of 
thinning out plantations and shrubberies ; one, whole¬ 
sale transplantation, entailing a considerable amount of 
labour, and often shirked accordingly ; and the other 
the destruction, in the shape of cutting down or rooting 
out of much that might well have been saved. If the 
thinning out had been taken in hand before the trees 
and shrubs had overrun each other, those not required 
for their present position could be safely transplanted 
elsewhere, much other effective planting up being done 
largely with the aid of these thinnings. This, as it 
happens, is not the time of year to commence tree 
moving, though much could be safely done during the 
month of April. Not a few of the choicer specimens 
of Conifers especially, could, however, be yet prepared 
for moving next autumn, a trench being opened round 
them at a distance varying from 3 ft. to 9 ft. from the 
stems, according to the size of the trees, all wide- 
spreadiDg roots being cut cleanly through, and either a 
little good fresh soil or that turned out from the trench 
being returned. This must lead to the formation of 
many root-fibres nearer the stems, minimising the risks 
and much simplifying the work of transplanting next 
autumn. Not a few trees and shrubs of little value 
might also with advantage be grubbed cleanly out -at 
the present time. Left where they now are, 'they only 
overshadow and greatly impoverish their much more 
valuable neighbours, and the longer they are spared 
the greater harm they will work. Poplars, being cheap 
and of rapid growth, are largely planted for immediate 
effect; but the majority ought never to be tolerated in 
shrubberies, and not long preserved in outlying plan¬ 
tations. A group of Lombardy Poplar near a private 
residence, though not necessarily or advisedly in the 
shrubberies, will in time become quite a feature in the 
landscape, and a landmark for many miles around ; but 
the rest of the species T would unhesitatingly slaughter. 
Elms, again, are cruel neighbours to any kind of culti¬ 
vated shrub, plant, or flower, the roots of these foraging 
and robbing the ground of fertility and moisture for 
many yards around. Therefore confine the Elms—and, 
in fact, forest trees generally—to the park or anywhere 
else, well away from the shrubberies, and flower and 
kitchen gardens. 
The beautiful Salisburia adiantifolia and the Tulip 
Tree may well have exceptions made in their favour, 
but even these are more effective as isolated specimens 
than in shrubberies. Nor would I tolerate the presence 
of the heavy Scotch Firs and several others of the more 
dense Pines anywhere near dwelling-houses or shrub¬ 
beries, where they soon overshadow everything else. 
Either isolate them or else cut them out. This rule 
may not be so strictly enforced in the case of various 
other Conifers, but the majority of these even are out 
of place in mixed shrubberies, being far more effective 
well clear of everything else in a Pinetum or on the 
turf. Whether only common Firs or more choicer 
species of Conifer, and whether planted in groups or in 
long belts at the outskirts of parks, the same rule 
holds good as to the necessity of the timely thinning 
out, all the trees being kept well clear of each other, 
and thus allowed to develop in a natural manner. 
Forest trees and Conifers are not the only subjects 
requiring thinning out and to be .otherwise attended 
to, the commoner kinds of evergiv, u ; frequently doing 
more harm to choicer species than even these. Too 
often common Laurels, Portugal Laurels, Aucubas, 
tree Box, common Yew, and also golden Elders, Dog 
Wood, and other strong-growing deciduous trees and 
shrubs, are allowed to extend as much as they will, 
these coarse, hungry-rooted kinds completely over¬ 
running the borders, as well as monopolising more than 
their share of head room. Many of them ought either 
