CHAPTER XI.
WINDOW GARDENING, AND THE MANAGEMENT
OF PLANTS IN POTS IN SMALL GREEN-HOUSES.
The management of plants in rooms is extremely difficult, from the want of proper light and pure air: though this latter want may, in some measure, be obviated, by opening the window in front of which the plants stand, whenever circumstances will permit. It should never be forgotten that fresh air is almost as essential to plants as water; and that they are seriously injured by being forced to inspire air at their breathing pores that is in an unfit state for them. I have often observed the healthy appearance of plants belonging to cottagers; and I believe it arises principally from the habit that most poor people have, of setting their plants out in the rain whenever there is a shower. This not only clears the leaves of dust, and opens the stomata or breathing pores, but gives the plant abundance of fresh air. Without a sufficiency of air and light, plants will soon become weak and sickly, and their leaves will turn yellow; but if a little fresh air be given to them every day when the temperature is not too cold, they will grow quite as well in a room as in a green-house.
Another reason why plants kept in rooms are generally unhealthy, is, that they are watered in a very irregular manner. Sometimes they are suffered to become so dry that the mould in which they grow will crumble under the pressure of the finger, and the spongioles of the roots are quite withered; and then a profusion of water is given to them, quite cold from the pump, though they have probably been standing in a temperature of from 60° to 70°. As a climax, part of this water is suffered to remain in the saucer for a day or two, till even the healthy part of the roots is thoroughly chilled, and the plant, if of a delicate nature, is destroyed. The reverse of all this should be the case. The plant should never be suffered to become so dry as to have the mould in a crumbling state; but if such a circumstance has been suffered to occur, it should be well watered with warm water of at least the temperature of the room, and better if rather warmer. Enough of this water should be given to fill the saucer; in order that every part of the mould and of the roots may imbibe some benefit from the moisture; but as soon as this has been done, the pot should be lifted out of the saucer, and the water thrown away, as nothing can be more injurious to the roots of most plants, than to have the pot they grow in, kept standing in water. There are, however, some exceptions to this rule, such as all the kinds of Mimulus, the Hydrangea, Calla ethiopica, and some kinds of Calceolaria. All these, and all marsh plants, require abundance of water, and will not flower well unless the saucer be kept half full, though the water should be changed every day.
It is also a common fault to put plants kept in rooms, into too large pots; or, as the gardeners express it, to over-pot them. This has always a bad effect. If the soil be good, and not over-watered, the plants will indeed grow rapidly; but it will be to produce leaves and branches instead of flowers: and if the soil be over-watered, the mass of soddened soil round the roots has the same effect upon them as stagnant water in the saucer. The soil should always be in such a state as to admit air with the water to the roots; and this it cannot do when it becomes a blackened paste by being saturated with water. At the same time frequent repotting is often absolutely necessary to keep the plants in a dwarf compact habit of growth, and to prevent them from being drawn up. The way in which gardeners ascertain when repotting is necessary, is by turning the plant out of its pot with the ball of earth attached; and if they find the roots look white round the outside of the mould, then the plant should be transferred to a larger pot; but only one size larger: afterwards it may be repotted again if necessary, but always to a pot only a little larger than the one it was taken from. By persevering in this mode of treatment for some time, and never advancing more than one size at a time, a plant may be grown to a large size, and made to produce abundance of flowers; while by the contrary treatment, that is, suffering it to remain in a very small pot, or shifting it suddenly into a very large one, the stem will become weakened and elongated, and the flowers will be few and very poor. In short, on the skilful management of repotting, or shifting, as the gardeners call it, a great deal of the art of growing plants in pots depends.
The best soil for plants in pots is generally peat mixed with vegetable mould and sand; and the pots should be filled nearly a quarter of their depth with little bits of broken pots, called potshreds, so as to ensure complete drainage. When plants are shifted, they are turned out of their old pots with their balls of earth entire; the roots are then examined, and if any are wounded or decayed they should be cut off. The new pot has then a layer of potshreds placed at the bottom with a little earth, and the plant is placed in the centre, so that the bole or collar may be just above the level of the rim. The new earth is then put in, and the pot shaken to make it settle. The plant is then slightly watered, and set aside in the shade for the rest of the day. Plants should never be repotted when in flower; the best time is indeed when they are growing, till their flower buds begin to swell, when they should be allowed to remain undisturbed till the flowering season is completely over. Sometimes the soil in a pot looks black, and covered with moss. When this is the case, the plant should be turned out of the pot, and the black sodden earth partly shaken off the roots, which should be pruned, and should have all their decayed parts cut off. The plant should then be repotted in another pot of the same, or nearly the same, size as the one it was taken from, which should be well drained, and filled up with a compost of vegetable mould, sand, and peat. Thus treated, and only moderately but regularly watered with warm water, which should never be allowed to stand in the saucer, the plant will soon recover; and if judiciously pruned in, if it has become elongated, it will become handsome, and what gardeners call well grown.
Another objection to growing plants in rooms is the great difficulty that exists in keeping them clear of insects; particularly the Aphis or green fly, and the kind of mite, (Acarus tellarius) commonly called the red spider. These are generally destroyed by fumigation; and the best mode of fumigating them is by Clark’s Patent Blower, with the fumigator attached, which has been already described. Washing with a syringe and abundance of water is, however, probably a better mode; as it has been often observed that neither the green fly nor the red spider will ever infest a plant, that is frequently syringed.
The management of plants in a small green-house differs very little from that of plants in rooms. Whenever the weather will permit, air should be given if only for half an hour in the middle of the day. The house should be kept clean, and free from dead leaves; and the plants should not be too much crowded. Nothing can look worse than pale sickly green-house plants, drawn up to an unnatural length, and so weak that their stems will not stand upright without the aid of a stick. When green-houses are crowded with plants, some of which are too far from the light, this must be the case; and when it is, it is quite hopeless to expect either healthy plants or fine flowers. Though it is adviseable to have saucers to the pots of plants kept in rooms, for the sake of cleanliness, it is much better for those kept in the green-house to be without them. As different green-house plants require a somewhat different treatment, the following directions for the management of a few of the most popular may be useful to my readers.
Camellias.—The Camellia is a plant which requires abundance of water, and is yet soon killed by suffering stagnant moisture to remain about the roots. When grown in pots there should be abundant drainage; that is, the pots should be more than a quarter filled with potshreds. The soil should be peat earth, mixed earth, and sand; and the plants should be potted high, so as to let the collar of the plant be quite above the rim of the pot. The pots should not have saucers, or if they have for the sake of cleanliness, the water should be carefully poured out of them immediately after the plants have been watered. The plants should be watered abundantly every day while their flower-buds are swelling, as if this be neglected, the buds are very apt to drop off. When the flowers begin to expand, the watering is not of so much consequence, though it should be continued in moderate quantities; and abundance should be again given when the plants are making their young shoots. After they have done growing, watering once or twice a week will be sufficient till the flower-buds again begin to swell. During the growing season the plants should be set out and syringed all over the leaves once or twice a week; but care should be taken not to do this when the sun shines, or at any rate not to set the plants in the sun while they are wet, as the heat of the sun acting on the water, will scald the leaves, and make them appear blotched, and partially withered. The roots of Camellias are seldom very strong, and they are very easily injured. Great care should, therefore, be taken when the plants are repotted not to bruise the roots, or to cut off all that are at all injured. If on turning out the plants previous to repotting, the ball of earth has no white roots appearing on the outside, the earth and decayed roots should be shaken or cleared away, till good roots are seen; and these should be carefully examined, and all the bad parts cut away. The plants should then be repotted in a pot not more than an inch in diameter more than the diameter of the ball of earth left round the sound roots; and it should be well drained at the bottom with very small potshreds, or clean gravel. Small Camellias should not be shifted oftener than once in two years; and large ones, that is, those above five feet high, not oftener than once in three or four years; but if the earth in the pot appears to have sunk, a little vegetable mould may be laid on the surface. The usual time for shifting Camellias is just when they have done flowering, before they are beginning to send out their young shoots. When planted in the free ground in a conservatory, they will require no other care than regular watering, and syringing the leaves once or twice a week. When planted in the open air, the roots should be carefully protected by straw during frosty weather. There are some Camellias in the Vauxhall Nursery, (Messrs. Chandler’s,) which have been treated in this manner, and have stood out for several years. The hardiest kinds and the most suitable for planting in the open air, are the single red, the double red, and the double white. The magnificent Camellia reticulata is also said to be tolerably hardy. The tenderest of the common kinds are the beautiful apple-flowered variety of C. Sasanqua, and the single variety of this species, the flower of which resembles that of the tea-plant. These plants are both of low growth, and ought always to be kept in pots.
Geraniums or Pelargoniums.—The beautiful green-house shrubs which we are accustomed to call Geraniums, have, in fact, been long separated from that genus, and formed into a new one called Pelargonium. The difference is in the shape of the seed vessel; that of the Pelargonium being like a stork’s bill, and that of the Geranium like a crane’s bill. Both are nearly allied to the Touch-me-not; and when the seed is ripe, the valves of the seed pod burst asunder and curl up. There are almost innumerable species, hybrids, and varieties of Pelargoniums grown in our green-houses, so mixed up together by hybridizing, that it is very difficult even to class them. One of the hardiest kinds, which has numerous descendants, is the Horse-shoe Geranium, Pelargonium zonale; and another, P. inquinans, is the common scarlet. The rose-scented Geranium, P. graveolens, and oak-leaved, P. quercifolium, with their numerous descendants, the flowers of which are all crimson, striped with brown so very dark that it looks almost black, are also tolerably hardy. All the shrubby kinds which are generally kept in green-houses, require a rich loamy soil, that is, about half very rotten dung, and half sandy loam, to make them produce fine flowers. When the flowering season is over, the plants are cut down, and cuttings made from them. (See page 82.) When these have struck, they are potted in a compost of vegetable mould and sand, and continue in this soil till February or March, when they are repotted in rich soil for flowering. Some gardeners throw away the old plants as soon as they have made the cuttings; but others take the old plants out of their pots, and shaking the earth from them, prune the roots, and repot the plants in smaller pots. Pelargoniums require a great deal of air; and when about to flower they should have a great deal of water, but at other seasons very little. They are killed with the slightest frost; and are very liable to damp off, if watered too much, and not allowed sufficient air in winter. Air is, indeed, quite essential to them.
Heaths.—The kinds grown in green-houses are all natives of the Cape of Good Hope, and they are very numerous; but they may be classed under six heads, which are named from the shape of their flowers. These divisions are tubular-shaped, ventricose, spreading or salver shaped, with an inflated calyx, globular, and ovate. They all require to be potted high, and to be grown in three parts of peat earth to one of fine white sand, or in what is emphatically called heath mould. The fine hair-like roots of heaths cannot penetrate a stiff loamy soil, and manure would be too gross for their spongioles to take up. The collar of the plant should always be above the soil, as it is very easily rotted by moisture. Heaths require good drainage, and frequent waterings; and though the water should never be allowed to stand in the saucer, the roots should also never be allowed to become quite dry, as when once withered, they are not easily recovered. Heaths also require abundance of free air, and no plants are more injured by being kept in rooms. They should not be shifted oftener than once in three or four years. They are propagated by cuttings taken from the tips of the shoots, and then struck in pure white sand. The pots containing the cuttings should be plunged up to the rim in a hot-bed, and each should be covered with a bell glass. Heaths are easily killed by frost, which acts upon them by splitting, or rather shivering their stems.
Verbenas.—No family of plants better rewards the care of the cultivator, and none can be more beautiful than the Verbenas. The old scarlet Verbena melindres, or, as it is frequently called, V. chamædrifolia, is the most brilliant of all the kinds, though it is one of the most tender: it is a prostrate plant, and when pegged down, it is well adapted for covering a bed in a geometric flower garden; or it may be planted in a vase, or rustic flower-basket to hang down over the sides. Verbena Tweediana is an upright growing plant, and though the flowers, which are crimson, are not half so brilliant as those of V. melindres, the plant has the great advantage of being one of the hardiest of all the kinds. V. melindres latifolia, and V. mel. splendens are both hardier than their parent, and they unite its brilliant colour, with the upright habit of Tweediana. V. incisa has pale pink flowers, and an upright habit of growth. It is tolerably hardy, and grows freely, but its flowers have a faded look. V. Arraniana has an upright habit of growth, and purple flowers, with very dark bluish-green leaves. It is very tender, and very apt to be attacked by a kind of aphis, and other insects. V. Aubletia, V. Lambertii, and V. Sabinii are prostrate tufted half herbaceous kinds, all hardy. V. Neillii has lilac flowers, and rather an upright habit of growth; and V. teucroides is a coarse-growing plant, with a long spike of white flowers, which turn pink in dying off, which has been much more praised than it deserves. There is also a yellowish kind, V. sulphurea; V. venosa, a very strong-growing species, with purple flowers, and many other species, hybrids, and varieties. All the Verbenas require to be grown in sand and peat, or heath-mould, and to be kept moderately watered: they all strike readily from cuttings or layers; and, indeed, when pegged down without any slitting or twisting, most of the shrubby kinds will throw out roots at every joint. When worm casts are observed on the surface of the pot, as will very often be the case, the plant, with its ball of earth entire, may be turned out of the pot, and the worms, which will always be found on the outside of the ball may be picked off. Worms do considerable injury to plants, especially such as are in pots, by rupturing the fibres and impeding the free percolation of the water, besides giving the surface of the earth in the pot, a very unpleasant appearance. The flowers of the Verbenas should always be cut off as soon as they wither. The Lemon plant, Verbena triphylla, now called Aloysia citriodora, is remarkable for the sweetness of the odour of its leaves. It is tolerably hardy; but requires great care in watering; as the leaves will soon curl up and wither if it has too little, and they will drop off if it has too much. The flower has no beauty; and the only recommendation of the plant is the delightful fragrance of its leaves.
Petunias may be raised, either from seed or cuttings, as they seed freely, and strike readily. The first kind introduced was the white-flowered kind, Petunia nyctaginiflora, which is an abundant flowerer, and very fragrant. Petunia phœnicea, or violacea, is another original species, and from these nearly all the myriads of hybrids and varieties have arisen. These Petunias hybridize freely with each other, and most of the kinds produce abundance of seed. P. bicolor is a different species, and does not either mix well with the others, or seed freely. Petunias may be treated as annuals, and raised on a slight hot-bed every year from seed; and thus treated, they will do very well in the open ground. In warm dry situations, they may even be suffered to sow themselves in the open ground, and will come up and flower abundantly. Treated as green-house plants, they are, however, all shrubby, and will last several years. When intended to be kept in pots, the seed should be sown on a slight hot-bed in February, and the young plants pricked out into very small thumb pots, as they are called, while in the seed leaf. In these pots they should remain either in the frame of the hot-bed, or in a room, or green-house, for about a week or ten days, and they should be then shifted into somewhat larger pots. These shiftings, always into somewhat larger pots, should be repeated six, eight, or ten times, if the plants are wanted to be bushy; and not more than four, if the plants are wished to grow tall. The bushy plants will flower abundantly, without any support; but the tall-growing plants, which are suffered to flower in comparatively small pots, must be trained to some kind of frame. When the tall plants appear growing too straggling, the extremities of the shoots should be taken off and made into cuttings. Petunias may be grown in any good garden soil; and require no particular attention as to watering, &c. In fact, they are, perhaps, the best of all plants for a lady to cultivate; as they will afford a great deal of interest and amusement, with the least possible amount of trouble.
Fuchsias are another family of plants that may be cultivated with very little trouble. Fuchsia globosa is at once the hardiest and the handsomest kind. F. virgata is also tolerably hardy. All the Fuchsias require a light, rich soil, or a mixture of rich sandy loam and peat; and regular watering, as when the outer roots are once withered, either by want of moisture, or by exposure of the pot to the direct rays of the sun, the plant generally dies. For this reason the Fuchsia is not so well adapted for a window plant, as many others. Fuchsia fulgens differs considerably from the other species, and will not flower well unless in the open ground, and with a sunny exposure. It is also tuberous rooted, though woody in its stem. It is easily propagated; and even a leaf taken off without injuring the part of the petiole which was attached to the stem, has been known to grow and form a plant. Several handsome hybrids have been produced, by applying the pollen of F. fulgens to the stigma of F. globosa, F. conica, and F. gracilis. It may here be mentioned, that whenever hybrids are to be raised, by fertilizing one plant with the pollen of another, the anthers of the flower that is to produce the seed, should be removed with a pair of scissors, before they burst. The pollen from the other flower which is to form the hybrid, should be afterwards applied with a camel-hair pencil to the stigma of the flower, which is to produce the seed; and a bit of thread should be tied round the flower-stalk, in order that the seed-pod may be saved, and set apart. All hybrids may be made in the same manner; but it must always be remembered that flowers will not hybridize properly, unless they are naturally nearly allied.
Calceolarias.—Perhaps no plants have ever been hybridized more extensively than these. The principal parents of the numerous and splendid plants that we are continually seeing produced, are C. corymbosa, and C. arachnoidea, the one a yellow, and the other a purple flower; but there are many other species that have been crossed and re-crossed with these, so as to form a very great variety. C. bicolor has a very large pale yellow-and-white flower; and it has been the parent of some very fine hybrids and varieties. All the calceolarias require rather a rich soil; and the usual compost is two parts of thoroughly rotten dung, one part of leaf mould, or old turf, and one part of white sand. The ingredients of this compost should be well mixed together, and broken fine, but not sifted. All the Calceolarias require plenty of water, and abundance of light and air; and they will all flower best when planted in the open ground. They are, however, very subject to be attacked by a kind of aphis; and when kept in pots, they should be frequently syringed.
Myrtles should be grown in a soil composed of peat and loam, in which the former predominates; they should be regularly watered, and frequently syringed. Some persons nip off the tips of the young shoots, to make the plants grow bushy; and though it has this effect, it is a bad practice with the flowering kinds, as it prevents them from flowering. A better plan is to make cuttings, and first to plant them in very small pots, gradually changing them into larger ones, till the plants have acquired a bushy habit of growth.
Mimulus.—Some of the kinds of plants of this genus are very handsome, particularly the hybrids raised by the nurserymen from M. cardinalis, M. roseus, M. luteus, and M. guttatus. These species are all herbaceous, and all natives of South America, Mexico, and California. They are all nearly hardy, and though generally grown in a green-house, they will stand quite well in the open air, dying down to the ground in winter, but sending up fresh and very vigorous shoots in spring. When these plants are grown in the open ground it should be in a shady moist situation; and when they are kept in pots, they should always stand in saucers half full of water. This water should, however, be changed every day, and when given to the plants it should always be as nearly as possible, of the same temperature as themselves. The little musk plant, Mimulus moschata, requires the same treatment as its more showy brethren. As all the species of Mimulus have been found in their native habitats growing in coarse sand or gravel on the brink of a river, this kind of soil should be chosen for them in pots; and the soil in which they are grown can hardly be too poor, provided they have abundance of water. In Chili, the inhabitants eat the leaves as a kind of vegetable. The shrubby kinds of Mimulus; viz., the common monkey plant, M. luteus, and the scarlet-flowered species, M. puniceus, are now considered to belong to a new genus called Diplacus. They are both natives of California; and in their treatment they should be considered as green-house plants, and have rather a better soil, and less water than the true kinds of Mimulus.
Hydrangea Hortensia is another plant, that when grown in a pot, requires to have the saucer kept half full of water. There are several species, most of which are hardy shrubs, but Hydrangea Hortensia, the kind usually called the Hydrangea, is a native of China, and only half hardy, though it will live in the open air in sheltered situations, or with a very slight protection. This plant was named Hortensia by the botanist Commerson in compliment to Madame Hortense Lapeaute, the wife of a French watchmaker. The Hydrangea, when the colour of its flower is to be pink, should be grown in a rich loamy soil; but when the colour of the flower is wished to be blue it should be grown in peat. In both cases the plant should be pruned every year, and the old wood cut out; so that the wood which is to produce the flowering shoots should never be more than two or at most three years old. Cuttings strike readily at any season when the plant is in a growing state; if put into a rich soil and kept moist they will root in a fortnight, and flower in a month.
Succulent plants.—There are very few things in gardening respecting which gardeners appear more to disagree than in the treatment of succulent plants. Nearly all these plants are natives of the sandy plains in the neighbourhood of the Cape of Good Hope, where they are subjected to alternate seasons of extreme wet and extreme dryness. Cultivators attempting to imitate this, have grown their plants in poor sandy soil, and kept them entirely without water at one season, while they have been inundated with it at another. The fact is, that when we attempt to imitate nature, we should remember that the attempt is useless unless we can do so in every particular; and also that the plants we have to cultivate, have been nursed up into so very artificial a state, that if they were transplanted to their native plains they would probably perish, like a poor Canary bird, which a mistake of philanthropy has turned out of the cage in which it has long lived. For this reason, we must adopt the mode of treating succulents, which the best gardeners find most successful, without troubling ourselves to discover why it is so different from the natural habit of the plants. This mode of treatment is, then, to grow the plants in a rich loamy soil, kept open, as it is called, by the addition of lime rubbish; and to give the plants water all the year, but more moderately when they are in a dormant, than when they are in a growing state. They should also have as much air and light as possible. The water should never be suffered to stand in the saucer of any succulent plant; but it should be given regularly, diminishing the quantity a little every day as the season for rest approaches. If the water be suddenly stopped the leaves of the plants will shrink and become flaccid, and when this is the case, the plant generally dies. A deficiency of air on the other hand will cause the plant to damp off. All succulent plants are very soon affected by frost.
The Australian plants, of which so many beautiful kinds have been introduced within the last few years, should nearly all be grown in a mixture of sand and peat; and they should have their pots filled one-third with potshreds. They all require abundance of water, but they will all perish if water is retained about their roots. Most of the Australian plants are very tenacious of life, and if cut down when they appear dead, they will generally spring up again from the collar or the roots.
The principal climbing plants grown in pots are the Maurandyas, the Lophospermums, the Passion-flowers, the Rhodochiton, the Eccremocarpus, the Ipomæas, and the Cobæa. There are, however, several others, all of which are very handsome. The greater part of these require a rich light soil to make them grow rapidly, and to be kept in small pots to throw them into flower. The Bignonias or Tecomas should be grown in equal parts of loam and peat; and this compost will suit the Polygalas, and other showy climbers. The Sollyas and Billiardieras should be grown in peat, and frequently syringed to keep off the green fly. The Thunbergias are very liable to be attacked by the red spider. Many of the shrubby climbers may be treated as annuals, and raised from seed every year in January, and planted out in June; but they do still better treated as biennials, and sown one year to flower the next.