The Gladiolus - Part 6
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Part 6

The _Nanceia.n.u.s_ strain, crosses between _Lemoinei_ and _G. Saundersii_, was introduced in 1889.

_Childsii_, originated by Max Leichtlin, Germany, was first disseminated in 1893. It consists of hybrids of _G. Saundersii_ pollinated with the finest Gandavensis varieties.

Lemoine's New Blue was first exhibited at the Chicago Exposition 1893 and placed on sale the following year.

_Gladiolus Princeps_, _Childsii x G. cruentus_, the finest scarlet variety ever raised, was introduced in 1903.

_Gladiolus primulinus_ and hybrids were first publicly offered in 1909.

[Ill.u.s.tration: PRINCEPS]

CHAPTER II.

Hybridizing Gladiolus.

The gladiolus, owing to the large size of the blooms and its open character, is one of the easiest plants to pollinate artificially.

Healthy vigorous plants should be selected for seed bearers, and the bloom spike supported with a firm stake. The blooms should be visited in early morning as they open, and the anthers removed before they have shed pollen, with the fingers, or better with slender forceps, taking care not to injure the style or the three-parted stigma, which will be ready to receive pollen about midday in bright weather or late in the afternoon, or even next day if cloudy or dull.

The blooms should, immediately after the anthers have been removed, be covered with thin cheesecloth, or "bobinet," firmly tied or pinned in such a manner as effectually to keep out bees and visiting insects.

Ordinary mosquito netting will not serve after it has been wet with dew or rain, as the mesh becomes so loose that energetic little pollen carrying bees force their way through, often entirely spoiling results.

The pollen-bearing blooms should be carefully selected to open the same day and should be as well protected with muslin or fine netting as possible to prevent robbery of pollen.

About noon, when the anthers are covered with dry-dust-like pollen they can be pinched out with forceps and carried to the seed-bearing spikes in a covered dish to protect from wind. The anthers may be taken separately in the fingers, or with forceps, and lightly brushed over the stigmas, which should be erect and open if they have reached the receptive stage. One anther will usually suffice for a seed bloom if pollen is abundant, but in some of the lighter-colored varieties it is scantily produced and several may be needed. Occasionally the anther valves do not open freely enough to permit the escape of pollen, which may then be taken out with a narrow-bladed penknife, or better with a little instrument made of a flattened pin fixed in a wooden handle.

The pollinated blooms should immediately be covered with the netting, which should remain until they fade. If conveniences are at hand the work may be rapidly accomplished--several hundred pollinations being made in a single day by an active worker. Pollen can also be used from cut blooms, the spikes being kept in water in a light room, free from flies or bees, but it gradually loses power when the upper blooms open under such artificial conditions. If the work is carefully done the resulting seeds will produce hybrids or cross breeds as the case may be, and it is always possible that the ideal sought for may appear among the number. Pollen may be kept a week or more by drying in the shade and wrapping in paraffin paper, but is far less reliable than if applied fresh from the anthers.

The blooms of large garden varieties are rarely self-pollinated, even if left uncovered, but the chances of fertilization with inferior kinds, generally the most abundant pollen producers, are so great that it is well to protect all seed-bearing blooms from insect interference. If the work is to be done on a large scale sleeves of netting or muslin large enough to enclose the entire spike will be found serviceable. The ends may be drawn together by cords looped through the fabric, effectually barring out the meddling bees. If a greenhouse structure or even a well lighted room is available, the plants may be grown in large boxes or pots and taken inside when blooming. This is especially desirable in the case of rare species and varieties, as there is no interference from stormy weather. Every bloom can be pollinated and practically every grain of pollen utilized under these secure conditions.

CHAPTER III.

Special Care of Seedlings.

Rare or scarce gladiolus seeds, particularly those resulting from difficult crosses, should not be risked under ordinary garden or field conditions of growth. We naturally wish to bring to maturity every possible plant that the ideal we are breeding for may not be lost, if it should by chance be included in the number. If grown in pots or boxes the first season, with due care every good seed is likely to produce a vigorous bulb that may be planted out next year. I have found six-inch standard flower pots, after many trials, to be the most convenient receptacles for small quant.i.ties of seeds, though almost equally good results may be had from well drained wooden boxes five inches deep. The boxes may be a foot or more wide and 18 to 20 inches long, and should be new and clean.

On no account grow gladiolus seeds or bulblets successive years in the same pots or boxes without sterilization, lest disease be fostered.

Sterilization may be effected in the case of pots, by roasting an hour or more in an oven at a temperature above the boiling point of water, or by well soaking in bichloride of mercury or formaldehyde solution, described in a preceding chapter.[C] Boxes may also be roasted in the oven or soaked in sterilizing solutions, but it is best to use new ones if procurable. Boxes should have at least one-half-inch drainage hole to each sixteen square inches of bottom surface, as gladiolus seedlings greatly dislike waterlogged soil. An inch of pebbles, broken sh.e.l.ls or sterilized potsherds should be placed in bottom and pot or box filled to within one-half inch of top with light compost made of two parts rich loamy soil and one part sand, well mixed together. Some very old fine manure may be used, but it should be confined to the bottom third of the receptacle and not come into contact with the seeds or resulting bulbs.

The seeds previously rubbed free from chaff, should be thickly sown on the surface--one hundred seeds is not too many for a six-inch pot--and covered with one-half inch of clean sand. Water with a gentle spray until entire ma.s.s of soil is saturated, cover top with old burlap or bagging and place pots or boxes in a secure place where the temperature will not vary greatly from sixty degrees. But little more water will be needed until the plants begin to come up, which should be in about twenty days. A sunny situation in greenhouse or garden is needed to grow the seedlings to best advantage, but if in the latter, protection should always be given from beating rains as the tiny seedlings are very easily broken down during the early stages of their development. Water should be given with sufficient regularity to keep the soil constantly moist without becoming sodden and all weeds removed as they appear. The bulbs will mature in twelve to fifteen weeks from germination. Water should gradually be lessened as growth ceases and foliage begins to yellow until the soil quite dries out, when it may be pa.s.sed through a sieve and even the smallest bulblet secured.

[Footnote C: Page 59.]

The little seedling bulbs, ranging in size from a wheat grain to a hazelnut, keep best in dry sand and should be sown next season like peas in drills in the garden. Some of the strongest are likely to bloom the second year and all should produce flowers the third. If seeds are sown under gla.s.s soon after ripening, in early October, according to foregoing directions, the bulbs may usually be ripened off in March, cured in sand in a dry warm place and planted out in May, thus securing a few blooms the following Autumn, one year after gathering the seed.

Most of the bulbs thus treated should attain blooming size by the end of the first season. If only a few seeds of a rare variety are obtainable, very porous compost in five-inch pots or shallower boxes, the seeds sown near the edges, will give best results. The seedling gladiolus the first year is so slender and with such a small root system that considerable attention is needed to avoid excess moisture unless closely planted.

A useful modification of the above method is to replace the bottom of a box of convenient size with wire netting of one-half-inch mesh or less, sink it to within an inch of the top in the soil in a convenient sunny place in garden, fill with prepared compost, sow seeds and proceed in the described manner except that less attention will be required in watering than if entirely exposed to the air. Box and soil can be lifted out when the bulbs mature, the soil dried and sifted to secure every minute bulb. If a considerable quant.i.ty of seed is to be sown a board frame eight inches deep, with bottom lined with one-half-inch mesh netting, and sunk in the ground, will give complete security from moles and similar vermin. If ordinary poultry netting is stretched over the top, additional security against surface marauders is given. Hand hybridized seeds are too precious to risk in ordinary unprotected soil.

Five thousand seedling bulbs may be grown in a frame 46 feet, if seeds are thickly enough sown.

CHAPTER IV.

Gladiolus Species.

The following list includes the most important Gladiolus species, as recognized by modern botanists. Many species formerly included in the genus _Gladiolus_ are now correctly a.s.signed to _Acidanthera_, _Antholyza_, _Babiana_, _Freesia_, _Montbretia_, _Tritona_ and _Watsonia_. Most true Gladiolus species will hybridize together, under favorable opportunity, but all attempts to breed the above genera with Gladiolus, thus far, appear to have failed. The most important garden hybrids of Gladiolus, useful in breeding work, have been described in preceding chapters. An attempt is here made to note the height of each species, the season of bloom in the northern hemisphere, the native locality where known, and the approximate date of introduction to cultivation:

Gladiolus adlami, dull yellow with minute red spots, Transvaal, 1889.

" alatus, 3/4 ft., scarlet, yellow, June, 1795.

" alatus algoensis, 3/4 ft., orange, July, 1824.

" albidus, 1 ft., white, June, 1774.

" angustus, 2 ft., yellow, June, 1756.

" atroviolaceus, dark blue, purple, white, Palestine, 1889.

" blandus, 1-1/2 ft., flesh, June, 1774.

" brachyandrus, 2 ft., scarlet, whitish, Zambesi Land, July, 1879.

" brevifolius, 1-1/2 ft., pink, June, 1802.

" byzantinus, 2 ft., red, July, Turkey, 1629.

" campanulatus, 1-1/2 ft., light purple, May, 1794.

" carneus, 2 ft., flesh, June, 1796.

" caucasicus, Caucasus, 1842.

" cochleatus, 1-1/2 ft., white, red, March, 1829.

" Colvillei, 1-1/2 ft., bright red marked with pale purple. Hybrid.

" Colvillei, alba, white.

" communis, 2 ft., red, South Europe, 1596, July.

" communis albus, 2 ft., white, June, South Europe.