Very few directions for this department remain to be given; except for shifting plants, and a few observations on those that are most desirable for the Hot-house; which we will do in this month, considering May and June the best months of the year for that operation.
The days and nights will be very mild by this time, and the sashes in every favourable day should be opened both in front and top, so that the plants may be enured to the open air, which they will be exposed to by the end of the month, Leave in the beginning of the month the top sashes a little open every mild night, and gradually as the heat increases leave the front sashes and doors open. Continue to syringe them at least every alternate night, and if possible every night; and give them all, according to their respective wants, liberal supplies of water every day. Absorption amongst Hot-house plants is as great during this month as in any period of the year.
OF REPOTTING PLANTS, &c.
It is our candid opinion that this and next month are the best periods for shifting or repotting all or most of Hot-house plants. The end of August being the time always adopted around Philadelphia for that operation (and then they are done indiscriminately,) we will assign a few reasons for our practice.
First, that it is not congenial to the nature of these plants to have their roots surrounded with fresh soil, when they are becoming inactive; secondly, that there is not a sufficiency of heat naturally to quicken them to an active state when they are encouraged; and thirdly, being thus in new soil while dormant, they have a yellow and sickly aspect until they begin to grow; and the foliage thus deprived of its natural vigour will not appear so healthful again. Whereas, if they are shifted or repotted in this or next month, at which season they are between two stages of growth, they immediately, on receiving fresh assistance, and by the increasing heat of the summer, make new growths, are perfectly ripened before the approach of winter, and never lose that verdureal appearance they have attained. These are our reasons acquired from a close practice and observation, and are not influenced by the doings of others which are so much aside. No practical operator especially, nor in fact any individual, ought to be governed by custom in regard to the treatment of plants, without having an idea as to why and wherefore, founded on the principles of nature, and governed by her unerring results.
As many are desirous of having a knowledge of plants, before they order them, and likewise which are the finest flowerers and their general character, especially those who are at a great distance, and seldom have the privilege of seeing what is most desirable, our descriptions will be limited, and simply such as are given for the Green-house in March.
Acàcias. Several of these are desirable in the Hot-house, for the grandeur of their foliage, beauty of flower, and a few of them as specimens of valuable medicinal plants. A. Houstóni, now Anneslèia Houstóni, is one of the most magnificent of the Mimòsa tribe, blooming from August to November in large terminale spikes, of a crimson colour, stamens very long, and beautiful; leaves bipinnated in pairs. A. grandiflòra, likewise given to Anneslèia, and similar to the former in colour; has very large compound bipinnate leaves, with from twenty to forty pairs. A. Catèchu, flowers yellow, wood spiny, leaves bipinnated, about ten pairs. The inner wood of this tree is of a brown colour, from which the Catèchu used in medicine is prepared. It is disputed whether A. Véra, or A. Arábica produces the gum Arabic. We are inclined to think it is the latter, which grows principally on the Atlas mountains. The gum exudes spontaneously from the bark of the tree in a soft half fluid state. There are many others of this genus belonging to the Hot-house, but being shy in flowering, are not generally esteemed. Most of the flowers have the appearance of yellow balls of down, and are hermaphrodite. The pots should all be well drained.
Aloe. These grotesque looking succulent plants are principally natives of the Cape of Good Hope, and consequently will do well in the warmest part of the Green-house, although when convenient, they frequently get a situation in the Hot-house. It is not requisite, except for A. vulgàris, known as A. barbadénsis; which has orange yellow flowers; A. oblíqua, now called Gastèria oblíqua; A. dichótoma; and A. lineàta, which is perhaps the finest of the genus. The leaves are beautifully striped, with red spines, flowers scarlet and green. These are the only ones that actually need heat during winter. They ought to have very little water, once a month is sufficient. They would grow without it, and several of them would also grow by being suspended in the house, without earth or any substitute about their roots, by being frequently sprinkled with water.
Few of them are admired for the beauty of their flowers, but the whole are considered curious. They flower from May to September.
Ardísias, about eighteen species. Plants highly esteemed for the beauty of their foliage, flowers, and berries. The most popular in our collections is A. crenulàta. It has rose coloured star-like flowers, in terminale panicles, and produces beautiful small red berries, which continue until other berries are produced the following year, and frequently there may be seen on one plant, the berries of three successive years, thus being a very ornamental plant and very desirable. It is vulgarly called the Dwarf ever-bearing cherry. It will keep in a good Green-house, but not grow freely. A. solanàcea has large oblong leaves, narrowed at each end, and bears purple berries; A. élegans has entire, oblong, shining leaves; A. umbellàta, once A. littoràlis, is the finest of the genus for abundance of flower and beauty of foliage. The flowers are pink, in large decompound panicles, the leaves the largest of all the species, oblong, wedge shaped, nearly sessile, entire, smooth, and reflexed. They are all evergreens, and the pots should be well drained. They are natives of the East Indies, and delight in a high temperature.