April 16, 1S85. ] 
JOURNAL OF HORTICULTURE AND COTTAGE GARDENER. 
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Royal Society at 4.30 P.M. Linnean Society at 8 P.M. 
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2nd Sunday after Easter. 
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National Auricula Society’s Southern Show, South Kensington. 
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ON WATERING PLANTS. 
VERY gardener knows that plants are incapable 
of taking up food from the soil unless it be pre¬ 
sented to them in a liquid state, and that no 
matter how rich in suitable foods the soil may 
be, so long as it is kejit dry the plants are 
unable to partake of them. On the other hand, 
water in excess of what the plant requires is 
often as prejudicial to growth and health as the 
other extreme. To know how much water will 
be good for a given plant we must first learn something of 
its nature or of the conditions under which it grows naturally, 
for the great points to determine are the amount which is 
most congenial to a given species under given circumstances 
and the periods of growth when water should be applied or 
withheld. Taking Nature as a guide first of all, we find 
many plants thrive under often very diverse conditions as 
regards soil and moisture, as, for instance, among the plants 
which are native of our own country the conditions under 
which the same species is found growing are often extremely 
varied. This is sometimes to be accounted for by the 
mutable nature of the species, which enables it to adapt 
itself to a variety of conditions; but generally there is one 
set of conditions which are most suited to the welfare of a 
plant when wild, and if we could be certain that we know 
what these conditions were we might safely follow Nature as 
a guide in the cultivation of such plants. For hardy plants 
there is, as a rule, less difficulty in affording the conditions 
supplied to them by Nature; but for plants cultivated in pots 
under glass this is not so easy, and sometimes it is quite 
impossible. We will, therefore, consider here the question 
of watering in its relation to the management of plants in 
pots, as harm is more frequently done by careless watering 
for them than it is possible to do to plants growing in the 
open ground, which are less dependent on the watering pot 
for their food. 
To treat this subject in such a manner as the extremely 
varied nature and requirements of the hosts of indoor plants 
would necessitate, dealing with each group separately, would 
require a much longer paper than is intended. We can only 
deal with it in a general way by pointing out the most im¬ 
portant points to be considered. Bearing in mind that all 
the materials (except a very small fraction obtained by means 
of the leaves from the atmosphere) out of which a plant builds 
up itself are conveyed into it by means of the fluids absorbed 
by the roots, which fluids must be supplied as water, and 
that in addition to what is so used there is also a very large 
amount of water given off through transpiration, it must be 
apparent that the quicker the growth of the plant and the 
larger the leaf area the greater must be the supply of water 
at the roots. Plants which grow slowly and which have not 
a large leaf area will, on the other hand, require less frequent 
supplies. In a moist atmosphere such as a stove there is 
much less transpiration (perspiration) from the foliage of 
plants than in an exposed well-aired house. All large-leaved 
thick-rooted plants require an abundance of water when 
growing: plants with small leaves and fine roots, such as 
Heaths, Leschenaultias, &c., being satisfied with much less. 
Palms, Crotons, Drachmas, Begonias, Agaves, Cycads, and 
many others require to be kept constantly moist whilst 
growing; the two last-named genera differing only in their 
habit of resting during winter, when they will do with a 
scant supply of moisture. This is the golden rule with 
regard to watering, no plant should be allowed to get dry 
during its growing season, and it is owing to neglect of this 
rule that so many plants are injured and often killed. 
The best example to illustrate how often harm results 
through allowing plants to get dry before they are again 
watered is the Ericas. There can be no doubt that for every 
five plants of this genus that are killed by an excess of 
water ninety-five are killed by allowing the soil to get too 
dry before giving them a fresh supply. In the nurseries 
where Heaths are grown by thousands they not unfrequently 
perish by hundreds through drought. In a hot summer 
these plants, which are usually grown in rather small pots 
by nurserymen and market gardeners, are dried in a very 
short time if not frequently watered, and as watering is 
deferred till the plants show signs of drooping it is often too 
late to prevent fatal results. I had worked this out to my 
own satisfaction some time back, and I was pleased recently 
to hear from one of the first Heath growers in England that 
last season he was forced to the same conclusion. With the 
drainage and soil arranged so as to prevent stagnation it is 
impossible to give too much water to a healthy plant when 
making vigorous growth if it is supplied at reasonable in¬ 
tervals. There is, of course, another evil consequent on 
excessive watering, and that is its effects on the soil; but it 
must be plain to anyone who thinks for a moment that to 
check the absorption of food by the roots, as is done when the 
soil is allowed to get dry, is to seriously interfere with the 
growth of the plant, and in the case of delicate kinds to cause 
serious injury. 
There is, however, a group of plants which thrive only 
when the soil about them is kept uniformly saturated; of 
these, Sarracenias, Nepenthes, Droseras, many forms, and 
Aroids are familiar examples. Naturally these plants are 
either semi-aquatic or are found wild only in very moist 
climates, and we are therefore bound to supply them with 
conditions similar to those such plan : s are always found in 
in a state of nature. Many Orchids must be placed under 
this category ; in fact, there is no Orchid to which abundant 
supplies of water is uncongenial during its season of growth. 
In the case of Cattleyas we have almost reformed the old 
system of partially dry treatment, which is now replaced by 
one of abundant moisture whilst they are growing, with a 
less liberal supply during their resting time. Nature has 
come to our assistance here, for collectors tell us that Orchids 
of all kinds are found in greatest abundance where the con¬ 
ditions include excessive moisture during at least a portion 
of the year. A study of the geographical distribution of 
these plants points to the same conclusion. We are, there¬ 
fore, by the above facts driven to adopt that treatment for 
plants in pots which supplies them wfith uniformly moist 
conditions at the roots when growing, large-leaved rapid¬ 
growing plants to have a regularly abundant supply, and 
those with small leaves and of a slow-growing nature suffi¬ 
cient to keep their roots continually moist. 
The second point to be considered is the resting period 
which almost all plants require. There is a popular belief 
that a plant cannot be rested unless it be subjected to total 
dryness at the root, and so far as regards a large proportion 
of the plants we cultivate this is no doubt correct. But there 
are many plants which are never naturally subjected to 
periods of drought. In temperate and northern countries 
vegetation is forced to rest by lowness of temperature accom¬ 
panied by much wet. Take as an instance the resting 
season for the plants of our own land. Here we have much 
more moisture as a rule in winter than in summer, and yet 
No. 251.—Yon. X., Third Series 
No. 1907.—Yol. LXXII., Old Series, 
