Even on good ground celery should not be set out later than August 15th (in the latitude of Philadelphia), and preferably earlier.
The system of level planting is practiced by large growers everywhere. Trenching is still followed in some private gardens, but is too expensive for commercial operations.
Varieties.—The so-called dwarf and half-dwarf varieties have pushed the larger kinds out of the market almost entirely, though seed of the giant sorts can still be obtained. The dwarf kinds are large enough for all purposes, however, and are in best favor everywhere. They are about 18 inches high, as compared to twice that height in the old-fashioned giant types.
The favorites of late years for early celery are the self-blanching sorts, such as White Plume and Golden Self-Blanching, which are the result of the continued selection of individual plants or sports showing a tendency to blanch easily. For winter keeping, the Perle Le Grand, Winter Queen and Perfection Heartwell are the best. These varieties are beautiful as well as highly palatable. There are also red or pink sorts, of high table merit and good keeping qualities.
Celery.—We recommend Golden Self-Blanching and White Plume for early, Perle Le Grand for both early and late and Winter Queen for late. The latter is the very best keeper. See "Johnson & Stokes' Garden and Farm Manual."
Cultivation.—The proper culture of the celery has already been suggested in the allusion to its need for water and its shallow feeding habits. The surface soil should be highly enriched, the stirring of the soil very shallow, and the water supply copious, either by capillary attraction from below (as at Kalamazoo) or by rainfall or artificial irrigation.
Blanching.—The first step in the process of blanching or bleaching is what is known as handling. This operation consists in grasping all the leaves of a celery plant in one hand, while with the other the soil is drawn together and packed so as to hold the stalks in an upright, compact position. This single operation will fit some of the early-planted sorts for market in the course of two weeks; though a second operation, called hilling, is usually considered desirable, even with the self-blanching sorts. See photograph on first page.
The Kalamazoo growers depend on muck for field blanching, though they also use boards. Muck is merely a dark soil, containing or consisting mainly of vegetable matter. They first "handle," as just described, and about five days later draw 6 inches more of the muck about the celery stalks. Again, three days later, they draw an additional 2 inches about the stalks, and in two weeks from the start the celery is ready for market.
These operations are frequently done by two men working together, one holding the stalks and the other drawing the soil to them. The first operation puts the stalks in an upright, compact position, so that little or no soil can get into the heart of the plant. The second draws about the plant all the soil that will conveniently remain there. The third merely supplements the second, as the hill has had time to become somewhat firm and has settled away a little from the upper leaves.
Boards are used for summer blanching, as they are less heating than soil. Ordinary lumber, free from knot holes, is employed. The boards rest on their edges, one board on each side of the row, the tops being drawn together until within 2½ inches of each other, and the lower edge of the board held in place either by stakes or by soil.