May 13, 1893. 
THE GARDENING WORLD. 
579 
My first attempts at pollinating were of the 
crudest description. I simply took the anthers 
from a double flower and placed them on the stigma 
of the one I wished to pollinate. This being my 
first attempt at pollination, and owing to the crude¬ 
ness of my method, I was not very successful ; but I 
succeeded in getting a fevv double flowers from the 
seedlings, flowers which would not be given a second 
glance now, but none of my best flowers of later 
production have given me half the satisfaction that 
those few poor ones did. They were double—there 
was no mistake about that—and they proved to me 
that I could grow double flowers if I wanted to. 
From that small beginning—I do net believe that I 
pollinated over a dozen flowers—I have continued 
year after year, getting a new strain from this man 
and another from that, to cross with those I already 
had. 
It may be prejudice on my part, but I must say 
that I have a strong partiality for a bed of Petunias. 
Hardly any other plant which is used for summer 
planting gives the satisfaction that the Petunia does. 
It is a rapid grower, a free bloomer, and is not, at 
least with me, troubled with insect pests. The best 
double flowers also make excellent pot plants, and 
give a constant succession of bloom throughout the 
entire summer. For pot culture, or for any one 
wishing to grow double flowers entirely, it is always 
better to procure plants of named varieties from a 
florist, but a packet of good seed will always yield a 
large percentage of double flowers. They will not 
all come double, as some always take after the 
female parent, the single flower, but at least half 
ought to be double. To me the great charm of 
growing seedlings consists in the uncertainty. One 
watches the flowers expanding. Is this going to be 
a double ? Is that ? Yes, here is one that there is 
no mistake about. Look at the mass of petals, still 
showing green, but there is not room in the corolla 
to contain them all, and one watches them, day by 
day, until the colour comes and the fully developed 
flower is there in all its beauty. 
To obtain the best result, I sow the seed in March, 
in either a hotbed or in the house in shallow boxes, 
covering it very lightly with fine soil. When the 
seedlings are about half an inch high, I prick them 
into small pots, and about the end of May plant out 
into the border. The Petunia is a gross feeder, likes 
a rich soil and an abundance of water, and the plants 
should have plenty of room for their development. 
I plant them a foot apart each way, and in a short 
time the ground cannot be seen between the plants. 
Owing to the constant hybridizing that this plant 
undergoes in the production of double flowers, it is 
almost impossible to give a description of the colours 
of any single variety propagated from cuttings. I 
could describe the colours and markings of 
each, but there is no certainty that they will 
all have the same colouring when they bloom 
again this year. I have had self-coloured flowers 
change to blotched ones the second year, and 
blotched varieties become self - coloured, and 
even from the same plant flowers can be picked 
which, when placed side by side, one would be 
positive came from two or more distinct plants. 
The general shape of the flower, and the fringing or 
frilling of the petals always remains the same in one 
variety, but the colouring changes. 
For the sake of any of my readers who might de¬ 
sire to try growing double seed, I will describe my 
system, which I find gives the best results. First, in 
order to have plants of strong vitality, in the late 
summer I pick out the best of the seedlings of that 
year, both double and single, and strike cuttings, 
which are wintered in the ordinary way in a cool 
greenhouse. Another point which I am particular 
about is, if possible, to see that all the single plants 
show signs of their double parentage. This may be 
seen in a small leaflet growing out of one or more of 
the anthers. These produce seed freely, although, 
as a rule, only when pollinated by hand. I never 
propagate for seed growing-from plants which have 
been for several years in cultivation, as I find that 
they seem to lose in vigour by constant propagation 
from cuttings. At the end of May I plant out in a 
sheltered spot in rich soil these wintered plants, the 
singles against a wire trellis and the doubles in the 
ordinary way, a foot apart. The single plants are 
trained to the trellis for convenience in pollinating. 
All the flowers that are not hand-pollinated are 
picked off, so that all the strength of the plants may 
be devoted to the development of the double seed, 
and that there may be no danger of mixing single 
seed with it. As soon as the flowers of the double 
plants are fully expanded they are picked, torn to 
pieces, and the anthers carefully picked out and 
placed in a sunny window to dry. As soon as the 
single flowers can be opened by hand, I remove the 
anthers with a pair of tweezers. This must be done 
before the anthers burst, for the minute they do this 
the flower is no longer of any use to the hybridizer. 
When the flower opens, the double pollen is applied 
to the stigma with a camel’s-hair brush, the flower 
is drawn into the shape of a bag and tied with 
thread, and the operation is complete. They are 
tied to prevent insects carrying pollen from other 
flowers, and destroying the efforts of the hybridizer. 
The principal difference between my system and 
that of most other growers is in planting the 
Petunias in the open ground. The claim is usually 
made that the seed is “ pot grown,” that is, from 
plants grown in pots. My contention is, and I think 
that I have pretty well proved it in practice, that a 
plant grown in a pot has not the vigour of one whose 
roots are allowed the range of a garden-bed, and 
consequently the pot-grown plant is not in a position 
to yield the same quality of seed as one grown in the 
open ground, while^ a continuance of the practice of 
pot-growing must necessarily impair the vitality of 
the parent plant, and through it that of its offspring. 
— G. A. McTavish, British Columbia, in American 
Gardener. 
—«■ 
Watering Vegetables. 
This is a matter which now claims daily attention, 
and if not well followed up, on light sandy ground 
especially, we shall get very poor crops this season. 
Watering, too, is not of much use unless mulching is 
systematically practised. It matters little what is 
used for this purpose so long as it keeps the ground 
moist by preventing evaporation. Straw litter, farm¬ 
yard manure, old Mushroom beds or even grass off 
the lawns are all useful. Early Peas are one of the 
first crops to suffer during weather like the present. 
All mine, both early and late, are mulched with 
rough straw litter and kept well watered. By this 
means I hope to get fair crops, even if the weather 
remains dry for another month, which there seems 
every prospect of its doing. The Cauliflowers 
planted out of pots, although these have been care¬ 
fully watered, are I see, hearting prematurely in many 
cases. The later ones that are now being lifted out 
of frames, I am shading with boards as they are 
planted, to keep them alive. Extra care must be 
taken to sow Lettuces in cool places, as it will be 
difficult to keep up the supply should we have a dry 
summer as well as spring.— G. II. S. 
General Work. 
Make successive sowings of Peas, and if ground can 
be spared a few extra rows should be sown this 
season, as some of the sowings with the dry weather 
will give short supplies. It is now time, if not 
already done, to sow Scarlet Runners and French 
Beans on a warm border. Thin Turnips as soon as 
large enough to handle and make more sowings. 
The early Carrots should also be thinned. The 
main crop of Beet may now be sown ; earth up 
Potatos as soon as they are high enough, as we may 
have frost any night yet. Give all fruit trees and 
Strawberries a good mulching and afterwards a 
thorough soaking of water. Now that the outdoor 
or natural Seakale is over, level down the ridges, 
and the plants will make fresh crowns, for earthing 
up next year, after the second year it is best to plant 
nevy ones.— G. H. S. 
The New Celery Culture. 
Some time ago (p. 390) I made reference to a buff 
variety of Celery that I had noticed during the past 
season growing in gardens by the wayside, and 
which was also represented as having certain good 
qualities. Not knowing the name, but surmising 
that it was White Plume, I asked if any of your 
readers had tested it from practical experience, and 
I gratefully acknowledge the replies that have been 
given, both home and colonial. I am still further 
interested in the note on p. 563 of your last number. 
The advent of this light-coloured variety into our 
gardens will no doubt give an impetus to the new 
culture as there described, or at least lead some of 
us to give the system a trial, especially for the 
earliest supplies. The mode of culture seems to me 
to be both feasible and commonsense-like, as White 
Plume of itself is deficient in colouring matter, 
otherwise chlorophyll, and the bed and border 
system will still further exclude the light and air so 
necessary to the chemical prjeess of bleaching, 
which renders our plants the more tender and crisp. 
The adoption of too much manure, I think, would 
re-act against its characteristic colour, or, at least, 
force it unduly into seed. In any case the plants 
wonld require careful stalking in exposed situations 
or the first strong winds would literally mow them 
down. Thus protected, I do not see why a good 
quarter should not be as useful and as safe as a brake 
of Parsnips.— B. L., Lindley, May 8th. 
- -*► - 
©leanings fxrrmt th§ 
SrtEnce* 
Action of Sulphuric Acid on Trees and 
Shrubs. —Professor F. W. Oliver has been engaged 
for some time “ On the Effects of Urban Fog upon 
Cultivated Plants,” and in quoting from a letter 
written by Mr. W. T. Thistleton Dyer on the sub¬ 
ject, he says that sulphuric acid is the chief agent 
that causes injury to trees and shrubs because their 
parts are permanent. The sulphuric acid is also 
cumulative in its action, continually parting with 
some of its water and taking it up again. As the 
water is given off the acid becomes more concen¬ 
trated and then becomes injurious by abstracting 
water from the surfaces with which it is in contact, 
thus giving those surfaces a charred appearance. 
1 he dilute sulphuric acid deposited upon trees and 
shrubs by fog becomes concentrated during dry 
weather, and then acts upon them like a caustic. 
The quantity which may be washed away by rain is 
augmented by fresh deposits, so that as time goes on 
the gain is probably greater than the loss. If such 
is the case we cannot be surprised that evergreen 
species, particularly Conifers and others, with a 
rough or hairy surface, should ultimately succumb to 
such an injurious agency. 
Leaves Locally injured by fog. —When blotches 
only occur here and there upon the upper surface of 
a leaf, Professor Oliver attributes them to the action 
of an acid. When sections of the injured portions 
are examined under the microscope, the epidermal 
cells are seen to be the first attacked, and as they 
succumb to the corrosive action of the acid, the 
adjacent cells get killed in the same way till the acid 
has eaten its way, so to speak, from the upper surface 
of the leaf right through to the lower. The proto¬ 
plasmic contents of the cells become separated from 
the walls. Leaves affected in this way do not, as a 
rule, drop from the plant, unless the fog is of long 
duration, or the affected area is large. The edges 
and tips of the leaves are the parts most commonly 
injured in this way, due, no doubt, to the moisture 
from the leaves collecting there, taking with them 
the injurious deposits. As the moisture evaporates 
the deposit becomes concentrated. After several re¬ 
petitions of the process, there would naturally be an 
accumulation of the poisonous deposit, hence the 
probable reason for the leaves being injured in those 
places. 
Fog causing leaves to fall —This is explained 
by Professor Oliver as due, not to deposit upon the 
surface of the leaf, but that the fog actually pene¬ 
trates the Jeaves through their stomata, and circula¬ 
ting through the intercellular spaces of the leaf comes 
in contact with the thin and delicate cell walls which 
can offer but a feeble resistance to the poisonous 
gases invading them. Passing through the cell walls 
they come in contact with and disorganise the cell 
contents. Further, it depends upon the constitution 
of the protoplasm and its power of resistance as to 
the amount of injury which the leaves of any given 
species will suffer. This is proved by the fact that 
many plants with thin walled and tender looking 
leaves escape injury, while the leathery leaves of 
other plants drop wholesale while still green, and to 
the naked eye apparently uninjured. Some leaves 
become withered and brown at the edges, and often 
more or less rolled up there. Most of them drop 
but in a few species they remain attached to the 
plants. Examination under the microscope shows 
that in all these cases the protoplasm is more or less 
disorganised and separated from the cell walls. It 
becomes discoloured in places, but the leaves drop 
in many cases while the discoloration is very local 
or altogether absent 
