THE POTTING AND BASKETING PROCESS
We are often asked what season is the best for potting and basketing
Orchids. Experienced growers say that, with the exception of the winter
season, they are engaged in potting operations all the year round,
potting each section as it requires it. Springtime is a period when a
general overhaul of the plants is usual, and, at that time, plants
requiring it should be repotted, but those which are not in the proper
condition, or which are showing flower-spikes, should be allowed to
remain until their flowering time has passed.
As a general rule, it may be said that the best time to perform the
operation is soon after the flowering season has passed, and that no
plant should be repotted unless it really requires it; but any plant
which has become in a bad condition in the pot by being in unsuitable
material should be repotted at once, no matter what season it may be.
Care should be taken to use the pots and crocks in a thoroughly clean
condition. Broken crocks are generally used for drainage, although they
are not now placed in the pots to the depth of one-half or more, as they
used to be. The depth of the crocks varies from about one-third in
Cypripediums and terrestrial Orchids generally, to a rather greater
depth for Cattleyas, Laelias, and similar Orchids, the depth of crocks
also being varied according to the density of the material used, fewer
crocks being necessary when a mixture of Osmunda fibre, or other
material which lets the water through quickly, is employed in place of
peat.
Sand and crushed crocks or potsherds are used by many for mixing with
the potting material, but they may easily be dispensed with, or used
only in very small quantities.
Turfy loam carefully broken up and mixed in suitable proportions with
peat and Sphagnum-moss, or Osmunda, or Polypodium fibre, is necessary
for Cypripediums, the proportion of loam being greatest for the
stronger-growing plants; certain Selenipediums and Cypripediums require
quite one-half of that ingredient. Some good growers use loam fibre
with a sprinkling of leaves and broken crocks entirely for _Cypripedium
insigne_ and others of the green-leafed class, and also for Calanthes,
Phaius, Zygopetalums, and other plants.
In preparing the peat for use in potting, the bracken rhizomes should be
set aside to place as a layer over the crocks, with a little
Sphagnum-moss. Bracken rhizomes have been used with advantage instead of
crocks to form drainage for Odontoglossums, and some growers like it so
much for that purpose that the horticultural sundriesmen supply it
sterilised in bags.
The methods of potting and choice of material vary with different
growers, each pursuing in some matters different methods to those
observed by others. It is desirable that an Orchid grower should
endeavour to find out the best methods for his own circumstances and, if
the results are satisfactory, that he should adhere to them, for there
is no more prolific cause of failure than in continually trying
experiments recommended by others. The operation of potting or basketing
Orchids is very simple, and can be readily learned by observation. The
aim should be to avoid injuring the living roots but to leave the plant
firm in the pot.
[Illustration: PLATE III
DENDROBIUM WARDIANUM
(At the time the photograph was taken this plant bore 264 flowers.)]
BASKETS AND POTS
It is more in accordance with nature to grow epiphytal Orchids of
convenient size in baskets to be suspended from the roof of the Orchid
house, and in the case of subjects reputedly difficult to grow the best
results are often attained in this way. At the same time, this is due as
much to the plants being placed near to the glass of the roof, as to the
fact that the air has better access to the roots than when the plants
are in pots. Hence it is that for suspending plants of small and medium
growth, Orchid pans made in the same way as the flower-pot are found to
be a convenient substitute for baskets, as they are not so liable to
decay as wood-baskets.
Stanhopeas, Lueddemannias, Acinetas, and some other Orchids which
produce their flower spikes directly from the base of the growth, must
be grown in baskets to admit of the proper production of their flowers,
which, if grown in pots, are sent down into the compost and lost.
Gongoras, Cirrhaeas, and similar genera, which produce slender spikes of
flowers of drooping habit, are also best in baskets, as they produce
their flowers much more freely when the plants are suspended.
The Orchid pan, for suspending, is also equally good for Masdevallias of
the Chimaera section, a large number of Bulbophyllums and Cirrhopetalums,
and generally for plants of small stature which would be too far away
from the glass if placed on the stage. For the bulk of the collection
the grower has to use the ordinary flower-pots, which are still
unsurpassed for general purposes. The elaborately designed pots,
perforated with holes or slits, which were used for Orchids years ago,
are not necessary, for there is no defect in the ordinary flower-pot
which cannot be overcome by the careful and skilful practitioner.
Rafts and cylinders of teak-wood made in the same manner as baskets are
useful for some species, but it has to be remembered that plants on
rafts are liable to suffer from lack of sufficient moisture-holding
material around them. _Broughtonia sanguinea_, however, is never so
happy as when grown on a horizontally suspended raft without the least
potting material.
The great trouble with suspended Orchids, and one which precludes the
cultivator employing this culture for so many plants as he could wish,
is the drip they cause to the plants on the stages. No Orchid should
have another plant suspended above it; if it is not possible to avoid
this, the relative positions of the suspended plants should be changed
as often as possible; water should only be given them by "dipping" the
plants, and they should be allowed to drain thoroughly before being
again suspended. As many of the suspended plants as possible should be
arranged on each side of the path, and in other situations where there
are no plants immediately under them.
Narrow rafts 4 inches wide and 1 foot or so in height are suitable for
_Angraecum infundibulare_, _A. imbricatum_, and other scandent Angraecums
of similar growth. These should be fastened to the rafts with some good
Sphagnum-moss between the plant and the raft on the lower half, the base
of the plant and the raft being afterwards fastened in a flower-pot with
Sphagnum-moss, the raft leaning at a slight angle. Sphagnum-moss can be
added on the upper part as the plant grows, and, when sufficiently
rooted up the stem, it can be severed half-way up when the base will
produce new growths.
STAKING OR FIXING ORCHIDS
Some years ago, when large specimens were favoured, it used to be the
practice to stake or "stick" the plants, as it was called, some of them
exhibiting almost as many sticks as pseudo-bulbs. The sticks rapidly
decayed, often leaving the stumps to harbour fungus and cause injury to
the plants.
The compact specimens of the present day, when properly grown, require
no support from sticks. In respect to specimens of larger growth, such
as Aerides of tall habit, Laelias of the _L. purpurata_ class, and
Dendrobiums, when they require sticking at all, they may be securely
supported by one stick in the centre, to which one of the strongest
growths should be fastened, any others requiring support being looped to
the centre stick. The fewer sticks used the better.
Dwarf plants with creeping rhizomes between the pseudo-bulbs used often
to be secured when repotted by small wire pegs, and the custom is not
yet quite obsolete. Metal, especially galvanised iron wire, which is
most commonly used, is very injurious to any portion of an Orchid which
is allowed to come in contact with it. Such pegs are unnecessary, for
the plants can be fixed with the potting material, and later on the new
roots will effectually secure them.
In fastening Orchids on rafts or blocks, fine copper wire should be
used, and all the care possible taken to prevent it resting on the
rhizomes or stems, a small piece of peat or Sphagnum-moss being placed
beneath the wire where it crosses the plant. Where Orchids such as
Phalaenopsis are grown in baskets or hanging pans, the leaves should not
be allowed to touch the wire suspenders, or injury will result. Where
leaves too closely approach the wire suspenders during their growth, the
wire should be bent to avoid contact, or have a small shred of
cotton-wool or other material bound round it at the point of contact, if
the leaf cannot be drawn aside.
For staking Orchids, bamboo canes are preferable to common deal-wood
sticks.
LABELLING THE PLANTS
It adds much to the interest of a collection of Orchids, either small or
large, if a proper system of recording the plants is arranged for by
means of a stock-book, in which the name of each plant is entered as it
is acquired, together with the source from which it was obtained, and
any other particulars that may be required when the plant flowers. This
entry need only be brief, and generally one, or at most two lines will
suffice for each plant. If it is intended to keep the plants under
numbers, the left-hand margin should bear consecutive numbers from one
onward, but if it is desired to have the names on each plant, the names
in the stock-book should be arranged in an alphabetical manner. In some
collections where numbering is practised the number is written across
the top of the label, and the name written lengthwise when desired.
The common deal label is not suitable, because the base soon decays in
Orchid houses, causing danger from fungal growth, and rendering the
identification of the plant after the label has perished, or fallen
away, very uncertain. The lead number for clipping the rim of the pot,
or attaching to the wires of the basket or suspending pan, is less
objectionable, but they are only convenient where numbers are alone
used. Zinc labels and various other contrivances have been tried, but
the best and safest label, either for numbers or names, or both, is the
white celluloid label, obtainable in all sizes, similar to the ordinary
wooden plant label, and in the ticket form for attaching to the baskets
by means of fine wire. This kind of label does not decay as the wood
labels, and it may be cleaned and used again as long as it remains in a
perfect condition. Let all labels be made as small as possible
consistent with their being firmly fixed, as it detracts much from the
appearance of a house of plants if the labels are too much in evidence.
Care must be taken during repotting that the labels removed from the
plants should each be returned to its proper specimen. Much trouble may
be caused by mixing the labels.