Part 2
The bulbs of Daffodils, Tulips, Snowdrops, Scillas, &c., all conform very closely to the Onion in structure. It will be noticed that at the base of the Hyacinth, for example, is a flattish or deltoid mass of tissue. This is called the "disc" and is really the stem portion of the bulb. On the upper surface it bears a number of thick scaly leaves packed very close together, and rolled round each other, with the flower-spike in the centre; while from the under surface, the roots emanate when growth takes place. It may be easily imagined by the reader that if the "disc" were drawn out lengthwise, and if a space separated one scale-leaf from another, that the bulb would be very similar in appearance to an ordinary leafy stem. Nature, however, has a certain object in view in modifying the stems and leaves in such a manner that they are tightly packed away when at rest, within a brown protecting coat, so that they resemble the large scale-protected flower-buds that may be seen in winter on Horse-chestnuts, Lilacs, Ash, &c. The thick scale-leaves are really storehouses in which food has been stored up by the larger and broader green leaves that perform the functions of assimilation, respiration, &c., above the ground during the growing period.
When the bulb begins to grow, the food in the thick scale-leaves is drawn up to supply nourishment to the flower-stem, until the new green leaves can manufacture or elaborate a fresh supply in the sunlight from the raw materials drafted into them from the soil by the roots. Under favourable circumstances more food is elaborated than is necessary for the wants of the plant, and then extra growths or young bulbs called "offsets" are developed at the base, or rather the side, of the older bulb.
It should be mentioned here, however, that all bulbs do not vegetate in the same way. In many cases the original bulb persists for several seasons, as in the Daffodil and Hyacinth, for example; but in others it vanishes completely during the period of growth, and is absorbed, or swallowed up, as it were, by the flower stem. The most common example of this among bulbs is the Tulip, to which more detailed reference has been made at p. 133.
=Kinds of Bulbs.=--Most true bulbs are constructed like the Onion, Daffodil, Snowdrop, or Hyacinth, in having the scale-leaves rolled round each other, forming different layers or coats. Such bulbs are said to be "tunicated." In the case of the Liliums, however, the scale-leaves only lap over each other at the edges, and are arranged spirally round the central axis. These bulbs are called "scaly," or "imbricated," and are shown in the annexed sketch on p. 12.
The individual scales are much thicker at the base than at the apex, and in the case of tunicated bulbs, they are also thicker on one side than the other. By this arrangement, the various "coats" can be rolled round each other more tightly, and without wasting any space.
Illustration: SCALY BULB OF LILY.
=Definition of a "Corm".=--In outward appearance, many corms are so much like bulbs, that the two terms are interchangeable and loosely applied, at least, among gardeners. By cutting a "corm" through the centre lengthwise, a great difference, however, will be noticed in the structure. In the bulb, the "disc" is small and unimportant, while the scale-leaves upon it are the most conspicuous feature. In the "corm," on the other hand, the "disc" is the all-important feature, and is devoid of any thick scale-leaves upon it. The new growths appear on the top or sides, and the lines round the circumference show where the sheathing papery scale-leaves were attached. In the "corm" then, it is the disc, and not the scale-leaves, that is the great storehouse of food.
PLATE 4. DAFFODILS ELLEN WILLMOTT, (17. MDME. DE GRAAFF, 18. HORSFIELDI)
=Growth of a Corm.=--The vegetation of the corm is very remarkable, and somewhat resembles that of the Tulip. When a corm commences to grow, the reserve material within it is used up for the benefit of the flowers and leaves. The result of this absorbing process is that by the end of the season the old corm has almost vanished, or is reduced to a dry shrivelled, woody, and lifeless mass, incapable of further growth, and attached to the base of the new corms, as shown in the annexed sketches of Gladiolus and Crocus on page 14.
These new corms are the direct result of the work that has been done by the green leaves in the daylight, and after a period of rest, they go through precisely the same process the following season--vanishing themselves, but leaving others behind to carry on the work of producing flowers, and, if possible, seeds.
Illustration: GLADIOLUS. _o. c._ old corm; _c. r._ contractile roots; _n. c._ new corms with "spawn" (_s_.) at base.
Illustration: CROCUS CORM. _o. c._ old corm; _n. c._ new corm with growths.
=The importance of Green Leaves to Bulbs and Corms.=--If the reader wishes to be successful in growing bulbous plants in his garden he must have very great respect for the green leaves of his plants, and always endeavour to keep them in the cleanest and healthiest possible condition. From what has just been said about the production of new bulbs in the Tulip, and new corms in the Crocus and Gladiolus, it is obvious that the leaves play a most important part. Indeed, without their aid there would be neither bulbs nor corms to carry on the work of the plants from year to year. In the form of carbon-dioxide the leaves eat up the carbon and oxygen from the atmosphere. Under the influence of sunlight the gas is decomposed, so that the oxygen is given off again into the air, while the carbon is retained for the production of starch and other materials. These are elaborated in the cells of the leaves, and after undergoing certain changes pass down the stems and are stored up in the bulbs or corms beneath the surface of the soil. It is only _green_ healthy leaves that can perform this important work satisfactorily. When the foliage therefore begins to turn yellow and wither, it may be taken for granted that its work for the season is coming to a close, and the bulbs or corms are going to enjoy a well-earned rest. It should, perhaps, be mentioned also that leaves can only become green in day light; and although some bulbous plants like a certain amount of shade, it would never do to exclude the light from them altogether, or even to plant them in places where they could not get an adequate amount of sunshine, or diffused light, during the day.
SOIL FOR BULBOUS PLANTS.
Comparatively few of the bulbous plants mentioned in this volume will require anything better than ordinary good garden soil that has been deeply dug, contains a certain amount of well-decomposed manure, and is well-drained so that the water freely passes away. Such a soil will give general satisfaction, with the least amount of trouble, especially if it is inclined to be light rather than heavy.
To secure really first-class results, however, the soil in beds or borders that are to be planted with bulbs should be particularly well-prepared in advance. A heavy soil, that is, one inclined to hold water, and of a clayey nature, will require a good deal more labour to bring it into a proper condition than a soil that is already friable and in a fair state of tilth. The heavy soil should be not only deeply dug to a depth of two feet or more, taking care not to bring the lower layers to the surface in the operation, although they should be turned over and pulverised as much as possible where they are. Plenty of sand or road-grit should be incorporated with a heavy soil, not only to keep it "open," but also to increase its warmth--a matter of some importance in our cold wet winters. The upper layer of soil, say a foot from the surface, may be still further improved by the admixture of old cow-manure and soot. In very bad soils, powdered quicklime may also be added, not only to absorb superfluous moisture, but to render the soil sweeter and more fertile. On no account, however, should fresh, rank manure be dug into the soil just before the bulbs are planted, as the heat and gases generated by its decomposition are often injurious to the extremely tender tips of the young roots.
PLATE 5. (DAFFODILS 19. CYCLAMINEUS, 20. TRIANDRUS ALBUS, 21. PRINCESS MARY OF CAMBRIDGE, 22. GLORIA MUNDI, 23. SIR WATKIN)
An ordinary good garden soil--that is, one that is regularly dug, hoed, manured, and cropped with some class of plants--will only need to be well dug for bulbs, and to have some well-decayed manure and soot incorporated with it a week or two before planting. For some bulbs, such as the Mariposa Lilies (Calochorti), some of the bulbous Irises, and a few other kinds, it may be necessary to take particular pains with the preparation of the soil for them. Attention has been specially called to plants of this nature, where such has been considered necessary. It should be remembered that when bulbous plants are attacked by fungoid diseases, referred to at p. 145, it is very often the result of a badly prepared soil, and not to any inherent defect in the bulbs.
HINTS TO BEGINNERS.
There is a beginning to everything, and the cultivation of bulbous plants is no exception to the rule. It is probable in many cases that the beginner at bulb-growing falls into precisely the same errors as the beginner with other classes of plants. The most common error of all, perhaps, is that he wants to grow at once every bulbous plant known. He sees a book, like the present one for example, and admires the beautiful pictures of bulbous plants in it. The result may be--and I hope it will be--a keen desire to invest in the bulbs that can produce such charming blossoms. But this keen desire should be tempered with discretion. His garden may be only a small one, and perhaps already stocked with many other plants. As he cannot hope to get the whole of Kew Gardens into it at once, it would be as well to start with only a few _kinds_ of bulbs. I do not mean of a _few bulbs_ of _many_ kinds, as he is almost sure to be disappointed in the results. In these days of imperial thought it is no use thinking of producing an effect in a garden with six bulbs of either Snowdrops, Crocuses, Tulips, or Daffodils. It is as well to think of the larger bulbs like the Lilies and choice Hyacinths in _dozens_; of the medium sized ones like Tulips, Daffodils, Tritonias, and bedding Hyacinths in _hundreds_; and of the smaller ones like Crocuses, Snowdrops, Spanish Irises, Scillas, Chionodoxas, and Bluebells in _thousands_. The dearer and choicer kinds are better left alone, perhaps, until some advance has been made with the others.
=Buying Bulbs.=--To buy bulbous plants in dozens, hundreds, or thousands of course means money. The beginner, however, is not advised to buy large quantities of _all_ the kinds mentioned to begin with, as the cost might be prohibitive, or the convenience for their proper treatment inadequate. What is strongly recommended, however, is to start with a large number of any one, two, or three kinds as can be afforded one year, instead of frittering away the same amount of money over a few bulbs each of perhaps a dozen different kinds which will fail to produce the anticipated effect later on. It is much better, for instance, to buy, say 100 bulbs of cottage or Mayflowering Tulips, than to invest in 100 bulbs belonging to eight different genera.
The 100 Tulips would make a fine show in the garden, because there would probably be enough of them; whereas the other bulbs, although quite as handsome in their own way would be lost, or at least inconspicuous, owing to the small number of each in flower at the same time.
If only one or two kinds of bulbs can be bought in sufficient quantity each season, with care they can be increased each year afterwards, and need not be purchased again. This will permit of the purchase of a sufficient number of one or two other kinds the following year, and as these will increase and multiply in the same way, there will be quite a large number of excellent bulbs available at the end of a few years. Each season there is a larger and better display than the preceding one, and that is a result very rarely attained, even after several years' labour, and a lot of money has been spent, when the principle of having only a _few_ bulbs of _many_ kinds is adopted.
If the effect is not produced the first season, enthusiasm is likely to be killed, or the interest in bulb-growing may be seriously diminished.
The beginner is strongly advised to start with such easily-grown and effective bulbs as Tulips, Daffodils, and Spanish Irises, afterwards adding Montbretias or Tritonias, Gladiolus, Liliums, Chionodoxas, Scillas, Snowdrops, Grape Hyacinths, Crocuses, &c., according to fancy. Of course all these may be started with, but as stated before, each kind should be purchased in sufficient quantity to make a bold and effective display when in blossom.
PLATE 6. DAFFODILS (24. GRAND MONARQUE, 25. SOLEIL D'OR, 26. WEARDALE PERFECTION, 27. LULWORTH)
=A Word of Warning.=--Beginners must not run away with the idea that the largest bulbs give the most blossom. In many instances this is very far from being the case--notably with the florists' Hyacinth--which is a most deceptive bulb. Small heavy bulbs are much better than large light ones--that is light or heavy according to their size. In Daffodils, too, there is a good deal of variety in the shape and size of different varieties, some being naturally smaller than others, and yet capable of throwing fine blossoms. All healthy bulbs, no matter to what genus they belong, should be firm and solid, and not soft and pappy to the touch. A distinction must also be made between well-ripened "flowering bulbs," and those often advertised as "planting bulbs." The latter are perfectly sound, but being merely offsets from the "flowering" bulbs, are not likely to flower the first year after planting, although a few of the stronger ones may do so. When one can afford to await a couple of years, "planting" bulbs offer a cheap means of stocking a garden, as a thousand can be purchased for a few shillings.
The other hints, necessary for a beginner, will be found in the following pages attached to the different groups of bulbs or corms he may wish to grow.
HOW DEEP SHOULD BULBS BE PLANTED?
This question has been agitating the minds of gardeners for some considerable time, and has given rise to a certain amount of discussion. Some advocate very deep planting, on the strength of having discovered the bulbs of such plants as Snowdrops, &c., a foot or more beneath the surface of the soil without any decrease in vigour. On the contrary, it has been contended that the plants have shown unusual sturdiness, notwithstanding the amount of reserve material the bulbs must have expended before the leaves were able to reach the light. It is natural that bulbs that are left in beds and borders for a few years without lifting should be found at a greater depth than is generally recommended for the planting of new bulbs. In the course of time the soil is turned up more or less deeply, and any bulbs in it are almost sure to be buried deeper than they were before; or frequent top dressings of soil or manure may have been given, and thus place the bulbs still further from the light. It is possible, however, that bulbs get buried deeply owing to the downward pull of their own contractile roots referred to below.
Although I am not going to recommend very deep planting, there is one great advantage in having bulbs in the open air well covered with soil, viz., that the temperature of the soil at one, two, or three feet is often as much as 20 degrees higher than it is immediately on the surface during very cold and frosty weather. This is a wonderful provision of Nature for the protection of all kinds of roots and bulbs beneath the soil in winter.
In the following pages the average size of the bulbs or corms of different genera is given. It will be noticed that they vary from half an inch in diameter in some of the smaller Narcissi, to three, four, or five inches in some of the Liliums. Between these two extremes there are nearly all shapes and sizes, and it is not unnatural that the amateur should be somewhat puzzled as to the depth he ought to plant any
## particular bulb.
For planting bulbs in the open air, I venture to propound a safe general rule, viz.:--_cover a bulb or corm with about twice its own depth of soil_. Thus a bulb one inch through from top to bottom would be planted about three inches deep, so that it would be covered with two inches of soil. The adoption of this principle means fairly deep planting in the case of large bulbs. There are a few exceptions, however, to this rule, but they have been noted in the proper place.
Illustration: DIBBER.
The actual planting of bulbs in formal beds may be done with either a garden trowel or dibber. The trowel is better for the larger bulbs like Liliums, and may of course be used for smaller bulbs if found to be more convenient. The dibber is useful for making holes at very regular distances apart in the lines, and into each hole a bulb may be dropped in, afterwards covering it over with soil.
Illustration: _Wrong_ and _Right_ way of planting Bulbs with Dibber.
A blunt dibber as shown in the sketch, will be found more useful than a pointed one for the work, although it may not be pushed into the soil so readily. The danger of a sharp-pointed dibber is shown in the sketch. A fairly large bulb is liable to be hung up in the hole as its diameter is greater than that of the dibber at a certain depth. Under these circumstances roots would not be emitted so readily from the base, as when the bulb is resting flat on the bottom of the hole as shown in the sketch to the right.
PLATE 7. GARDENIA NARCISSUS (28) POET'S NARCISSUS (29) HYACINTHUS AMETHYSTINUS (30)
THE NATURAL SINKING OF BULBS AND CORMS.
In connection with the question of planting, attention may be directed to a very interesting and remarkable power possessed by the roots of many bulbs and corms. A glance at the sketches of Gladiolus, Tritonia, Nothoscordum, and Lilium, will show the reader some thick fleshy roots with conspicuous rings on them. They are readily distinguished from the finer fibrous roots, and, as may be readily supposed, their functions are quite distinct. To thoroughly understand what these thick-ringed roots are for, the reader will remember what has been said at page 13 about the way in which the old corms of Crocuses and Gladioli disappear, or are surmounted in autumn by new ones. If the plants were not disturbed for several years, one would imagine that as the new corms were always produced _on top_ of the old ones, they would sooner or later come through the surface of the soil, and thus run the risk of being either parched by drought, or shrivelled up by the heat of the summer sun; or, again, of being frozen to death in winter. And yet, examination of the corms will show that the new ones are quite as deep down in the soil, if not deeper, than their predecessors. This remarkable state of affairs to preserve what may be called the _status quo_ is entirely due to the action of the thick, ringed roots referred to above. These roots usually strike straight down into the soil. When they have gone as far as Nature intended them to, they begin to contract much in the same way apparently as a worm does when going into its burrow, and for this reason they have been called "contractile."
Illustration: NOTHOSCORDUM BULB. Showing Contractile Roots.
Illustration: TRITONIA CORMS.
During the process of contraction a tremendous force must be exerted to enable the roots to pull the corms or bulbs down to their proper level in the soil. The passive resistance of the latter is overcome, and as a result its particles are pressed much closer together than they were before.
Sometimes this pulling power of the roots is exerted horizontally instead of vertically, and this accounts for the spreading of many bulbous plants like Tulips, Grape Hyacinths, &c., over a large area in the course of a few years when left undisturbed.
=Bulbous Plants without Contractile Roots.=--Some bulbous plants have not the advantage of contractile roots to keep them down in the soil, so they must secure this desirable end by different means.
Illustration: COLCHICUM. _o. c._ old corm; _n. c._ new growth; _o. r._ old roots.
Illustration: BULBOCODIUM. _o. c._ old corm; _n. c._ new growth; _o. r._ old roots.
A glance at the sketches of Colchicum and Bulbocodium will show a peculiar method of growth. The new corm instead of being produced on top of the old one, is developed at the side. Note, however, that the new corm is not on the same level as the old one. That would be no advantage whatever. Therefore it takes, as it were, a step _downwards_, so as to be well out of reach of mowing machines, rats, and mice, and other enemies, and also probably because it knows it will be much warmer in winter when several inches below the surface. The same principle seems to be employed by the bulbs of the Dog's Tooth Violets (_Erythronium_), as may be seen from the sketch--the new bulb to the right being distinctly lower than the older one to the left.
Illustration: ERYTHRONIUM.
PLATE 8. FRITILLARIAS (31. MOGGRIDGEI, 32. WALUJEWI, 33. MELEAGRIS ALBA, 34. RECURVA)
PROPAGATION OF BULBOUS PLANTS.
Perhaps there is no one class of plants that have so many ways of being easily increased as bulbous plants proper. Some kinds, _e.g._, Liliums, Alliums, may be increased in four different ways--from offsets and "spawn," scales, bulbils, and, last of all, seeds.
=Offsets.=--The great mass of bulbous and cormous plants, however, are so readily multiplied by detaching the offsets from the parent bulb or corm, that the other methods are rarely employed except by trade growers. Nearly all hardy bulbous plants produce offsets freely. These offsets represent a superabundance of nourishment that has been elaborated in the leaves, and very often there are several smaller ones attached to the base of the larger ones that have been produced in precisely the same way.
In the case of Daffodils, Tulips, Hyacinths, Crocuses, Gladiolus, and a host of others, the new offsets are pressed against the sides or on top of the older ones. In the drawing of the Tulip (p. 30), three new bulbs are to be seen surrounding all that is left of the old bulb. This latter has practically vanished up the main axis from the disc to produce flowers and leaves--hence it follows that the Tulip bulb somewhat resembles the corm in its vegetative characters. The bulbs taken out of the soil in early summer are not those that were planted the previous autumn.