This section is from the book "Culinary Herbs", by M. G. Kains. Also available from Amazon: Culinary Herbs, Their Cultivation, Harvesting, Curing and Uses.
A layer of earth is placed in the bottom as deep as the lowest tier of holes. Then roots are pushed through these holes and a second layer of earth put in. The process is repeated till the keg is full. Then plants are set on the top. As the keg is being filled the earth should be packed very firmly, both around the plants and in the keg. When full the soil should be thoroughly soaked and allowed to drain before being taken to the window. To insure a supply of water for all the plants, a short piece of pipe should be placed in the center of the keg so as to reach about half way toward the bottom. This will enable water to reach the plants placed in the lower tiers of holes. If the leaves look yellow at any time, they may need water or a little manure water.
As parsley is grown for its leaves, it can scarcely be over fertilized. Like cabbage, but, of course, upon a smaller scale, it is a gross feeder. It demands that plenty of nitrogenous food be in the soil. That is, the soil should be well supplied with humus, preferably derived from decaying leguminous crops or from stable manure. A favorite commercial fertilizer for parsley consists of 3 per cent nitrogen, 8 per cent potash and 9 per cent phosphoric acid applied in the drills at the rate of 600 to 900 pounds to the acre in two or three applications-especially the nitrogen, to supply which nitrate of soda is the most popular material.
A common practice among market gardeners in the neighborhood of New York has been to sow the seed in their cold frames between rows of lettuce transplanted during March or early April. The lettuce is cut in May, by which time the parsley is getting up. When grown by this plan the crop may be secured four or five weeks earlier than if the seed is sown in the open ground. The first cutting may be made during June. After this first cutting has been made the market usually becomes overstocked and the price falls, so many growers do not cut again until early September when they cut and destroy the leaves preparatory to securing an autumn and winter supply.
When the weather becomes cool and when the plants have developed a new and sturdy rosette of leaves, they are transplanted in shallow trenches either in cold frames, in cool greenhouses (lettuce and violet houses), under the benches of greenhouses, or, in fact, any convenient place that is not likely to prove satisfactory for growing plants that require more heat and light.
This method, it must be said, is not now as popular near the large cities as before the development of the great trucking fields in the Atlantic coast states; but it is a thoroughly practical plan and well worth practicing in the neighborhood of smaller cities and towns not adequately supplied with this garnishing and flavoring herb.
A fair return from a cold frame to which the plants have been transplanted ranges from $3 to $7 during the winter months. Since many sashes are stored during this season, such a possible return deserves to be considered. The total annual yield from an acre by this method may vary from $500 to $8oo or even more-gross. By the ordinary field method from $150 to $300 is the usual range. Instead of throwing away the leaves cut in September, it should be profitable to dry these leaves and sell them in tins or jars for flavoring.
When it is desired to supply the demand for American seed, which is preferred to European, the plants may be managed in any of the ways already mentioned, either allowed to remain in the field or transplanted to cold frames, or greenhouses. If left in the field, they should be partially buried with litter or coarse manure. As the ground will not be occupied more than a third of the second season, a crop of early beets, forcing carrots, radishes, lettuce or some other quick-maturing crop may be sown between the rows of parsley plants. Such crops will mature by the time the parsley seed is harvested in late May or early June, and the ground can then be plowed and fitted for some late crop such as early maturing but late-sown sweet corn, celery, dwarf peas, late beets or string beans.
When seed is desired, every imperfect or undesirable plant should be rooted out and destroyed, so that none but the best can fertilize each other. In early spring the litter must be either removed from the plants and the ground between the rows given a cultivation to loosen the surface, or it may be raked between the rows and allowed to remain until after seed harvest. In this latter case, of course, no other crop can be grown.
Like celery seed, parsley seed ripens very irregularly, some umbels being ready to cut from one to three weeks earlier than others. This quality of the plant may be bred out by keeping the earliest maturing seed separate from the later maturing and choosing this for producing subsequent seed crops. By such selection one to three weeks may be saved in later seasons, a saving of time not to be ignored in gardening operations.
In ordinary seed production the heads are cut when the bulk of the seed is brown or at least dark colored. The stalks are cut carefully, to avoid shattering the seed off. They are laid upon sheets of duck or canvas and threshed very lightly, at once, to remove only the ripest seed. Then the stalks are spread thinly on shutters or sheets in the sun for two days and threshed again. At that time all seed ripe enough to germinate will fall off. Both lots of seed must be spread thinly on the sheets in an airy shed or loft and turned daily for 10 days or two weeks to make sure they are thoroughly dry before being screened in a fanning mill and stored in sacks hung in a loft.
There are four well-defined groups of parsley varieties; common or plain, curled or moss-leaved, fern-leaved, and Hamburg. The last is also known as turnip-rooted or large-rooted. The objections to plain parsley are that it is not as ornamental as moss-leaved or fern-leaved sorts, and because it may be mistaken for fool's parsley, a plant reputed to be more or less poisonous.
In the curled varieties the leaves are more or less deeply cut and the segments reflexed to a greater or less extent, sometimes even to the extent of showing the lighter green undersides. In this group are several sub-varieties, distinguished by minor differences, such as extent of reflexing and size of the plants.
In the fern-leaved group the very dark green leaves are not curled but divided into numerous threadlike segments which give the plant a very delicate and dainty appearance.
Hamburg, turnip-rooted or large-rooted parsley, is little grown in America. It is not used as a garnish or an herb, but the root is cooked as a vegetable like carrots or beets. These roots resemble those of parsnips. They are often 6 inches long and 2 inches in diameter. Their cultivation is like that of parsnips. They are cooked and served like carrots. In flavor, they resemble celeriac or turnip-rooted celery, but are not so pleasing. In Germany the plant is rather popular, but, except by our German gardeners, it has been little cultivated in this country.
The Germans use both roots and tops for Cooking; the former as a boiled vegetable, the latter as a potherb. In English cookery the leaves are more extensively used for seasoning fricassees and dressings for mild meats, such as chicken and veal, than perhaps anything else. In American cookery parsley is also popular for this purpose, but is most extensively used as a garnish. In many countries the green leaves are mixed with salads to add flavor. Often, especially among the Germans, the minced green leaves are mixed with other vegetables just before being served. For instance, if a liberal dusting of finely minced parsley be added to peeled, boiled potatoes, immediately after draining, this vegetable will seem like a new dish of unusual delicacy. The potatoes may be either served whole or mashed with a little butter, milk and pepper.