Chapter 21

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 quantities 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 shells 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 mass 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 passed 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 glass 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 quantity 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 4×6 feet, if seeds are thickly enough sown.