THE COTTAGE GARDENER. 
37 
October 17. 
or who have seen the work done, would be able to dis¬ 
tinguish it from surrounding objects of years’ standing. 
With a reference to his excellent views respecting 
porous and non-porous flower-pots, we must draw to a 
conclusion. He says: — “ Thei’e are few gardeners, 
even at the present day, who have not a strong belief in 
the advantage of porous pots, for the growth and health 
of plants, over glazed and non-porous ones, or those 
made of zinc; but I have a decided opinion in favour 
of the latter, founded on the experience gained from 
much attention I have paid to the subject. The porous 
pot, simply from the fact of its being so, becomes, in a 
very short time, saturated with moisture ; and this very 
capacity for moisture renders it unfit for use; for 
example, the natural action of the plant not being 
active enough to abstract this moisture from the pores 
of the pot, causes it to have an unhealthy influence on 
the tender fibres of the plant which come in contact 
with its inner surface; and when it has been long in 
this stagnant state vegetation takes place on the out¬ 
side, first in the form of green unsightly slime, and 
then of moss; and hence, a great deal of trouble in 
washing it off, beside the injury to the plant growing in 
it. The glazed, or non-porous pot, absorbs no moisture, 
and is always clean. Evaporation of any excess of 
moisture after watering takes place from the surface; 
and the inner surface of the pot dries with the soil. 
Plants, as has often been proved at Trentham, carry a 
more healthy appearance than those under the same 
treatment, but in common pots. Zinc pots are even 
better than glazed ones.” 
We believe these zinc pots to be Mr. Fleming’s 
invention; or, at any rate, their introduction at Trent¬ 
ham is entirely owing to him; and it has often been 
observed by visitors, that the plants in zinc pots have 
a remarkably luxuriant and healthy appearance. 
We will close this memoir by drawing the attention, 
not only of young and aspiring gardeners, but of all 
young men whose future position in life rest mainly on 
the means used to acquire it—and those means are the 
same which have made Mr. Fleming so distinguished— 
Energy, Attention, and Perseverance.” 
BOTTOM-HEAT IN ITS RELATIONS TO 
ATMOSPHERIC TEMPERATURES. 
W hat is termed by gardeners bottom-heat, is, I fear, 
considered by many to signify some very high tem¬ 
perature of the soil or medium in which the roots of a 
plant are situated, almost irrespective of the air-heat. 
It is, doubtless, considered too abstractedly ; that is to 
say, without a due regard to the relation it bears to 
light and heat. If any tyro in horticulture should 
doubt the propriety of sustaining a proper relation 
between these important elements, let him boldly destroy 
their balance, for the sake of experiment; let him make 
up a hothed-frame at a period when a low air tempe¬ 
rature prevails, but no possibility of frost—say in Sep¬ 
tember or May—and let a bottom-heat of 80° be 
secured, and Cucumbers, or any other thing that will 
speedily show the effects of good or ill-management, be 
planted in such medium. We will now fancy them 
established, and then let him first try the effects of a 
comparative absence of light; we will not go so far 
as total blanching; let him fasten a canvass or other 
screen over the light, and he will soon find a thin, 
pale foliage, attenuated habit, and their necessary conse¬ 
quence, barrenness. 
Again, to test the temperature affair, let the same 
bottom-warmth be sustained, and let the atmospheric 
warmth be kept at a very low pitch, say 50° to 00®. I 
will not undertake to say precisely what result would 
appear, but the system of the plant would be completely 
perverted. These things being admitted, it is evident, 
that a proper consideration of the relation these elements 
bear to each other becomes a matter of much im¬ 
portance, not only as sustaining a healthy balance in 
the system of the plant, but as furnishing, by slight 
deviations, when requisite, from that exact balance, 
means whereby important objects may, at times, be 
carried out. I would here, more especially, point to its 
application to late autumn or winter-flowering plants, 
and even to forcing processes. In both these cases, the 
needs of forcing fruits or flowers are very different in 
character from those of the winter or spring. The 
autumn may, in broad terms, be called the period of 
consolidation, or, as gardeners have it, the “ripening 
period; ” the spring, the period of development. Of 
course, all the world know this, but I wish to make a 
special application by such reference. In winter or 
spring forcing, care is taken to nicely apportion the 
atmospheric warmth to the amount of light, as, also, 
the degree of air-moisture; as the process of mere de¬ 
velopment of parts already formed, and in an excitable 
condition, would not be carried out so well by imitating 
the arid conditions of an autumnal sky. 
This is all as it should be; but it is as much the good 
cultivator’s concern to feed and perfect those buds 
whence emanate blossoms or fruit, as it is to develop 
them in a proper way afterwards. The question, then, 
is, can those relations of heat, ventilation, and air- 
moisture, be so modified by the cultivator as greatly to 
facilitate the production of superior blossoms at the 
flowering or forcing period? I have now arrived at the 
point of my enquiries; and I do think I can make it 
appear that something may be done. * 
To illustrate the matter, I will call in to my assistance 
a few things with which all are familiar; for such, 
indeed, will best serve our purpose. The Neapolitan 
Violet: everybody kuows this, and most gardeners culti¬ 
vate it. Now, this Violet may be had in blossom, in a 
continuous way, from the end of September until the 
middle of May, or even later; and that, too, from one 
plant, or one set of plants. It is with us propagated 
in May or June, from runners or cuttings, and receives 
good culture through the summer mouths. In the very 
beginning of September, they are planted in a brick-pit, 
and here they remain until the end of March, when the 
pit is required for other purposes. 
Such a pit, of the finest young plants I ever saw, I 
have now, and I am putting in practice, daily, the very 
principles I have here alluded to. I have a bottom-heat 
of about 70°, produced by dung and leaves trod firm ; this 
heat will be of an abiding character for about three 
weeks; it will then speedily decline, as I wish it, being 
composed, in the main, of leaves in a highly-decomposed 
state, and by the middle of November, or sooner, will 
be quite cool. The plants have not received a drop of 
water from a pot—merely syringed ; and the lights are 
propped up, bottom and top, for the wind to blow 
through them, or even just to have a smell occasionally 
of one of those little autumn hoar frosts which make 
careful gardeners begin to put their house in order. 
Now, I have not tried the air-heat of this pit, but, 
assuming that the average day-heat, for a week, is about 
60°, and of the night, about 50°, here will be an advantage 
of a dozen or fifteen degrees in favour of a bottom-heat! 
