The Maryland Station (Maryland Station Bulletin 133 (1909), p. 197) has made a thorough study of the chemical composition of the cabbage. The following tables are adapted from the report upon this subject:

Food Constituents In Heads And Refuse Cabbage

It will be seen from this table that cabbage is a very watery food, but that the amount of protein in the dry matter is relatively large.

Fertilizing Material Found In The Different Parts Of Cabbage Plants

(Per cent in Fresh Materials)

354. Manure And Fertilizer Requirements

Figuring on the basis of 8,000 mature heads to the acre, each head weighing 3 1/2 pounds, an acre of cabbage would require during the season the following amounts of plant food:

Pounds Of Fertilizer Found In Cabbage From One Acre

To furnish all of the plant food for this yield of 8,000 heads, or 14 tons an acre, would require the equivalent of 165 pounds of phosphate rock of 14 per cent grade, 228 pounds of muriate of potash of 50 per cent purity and 447 pounds of nitrate of soda of 15 per cent purity. The total cost of these materials an acre would not exceed the amount frequently applied, but the proportions—3 per cent phosphoric acid, 14 per cent potash and 8 per cent nitrogen—would be unusual. The analysis shows, however, that potash is very important in the production of this crop, and that nitrogen should be supplied in larger amounts than is usual. It is not necessary to use potash so freely in clay soils, but it is highly probable that 10 per cent of this element is not too much for most other soils. Although the phosphoric acid requirements are relatively small, the grower should not lose sight of the fact that most soils are very deficient in this element, and there are doubtless localities where it should be used more freely than potash. The most successful growers seldom use less than 4 per cent of nitrogen, and the analyses indicate that this is the minimum amount that should be used, unless there has been a large application of manure. The basic fertilizer, 4-8-10, should meet the requirements of most soils, especially if nitrate of soda is used later as a top dressing.

Fifteen hundred to 2,000 pounds of fertilizer are generally used for the early crop, and many growers of late cabbage do not apply less than these amounts. It is especially desirable to use large amounts of highly nitrogenous fertilizers for the early crop, to hasten maturity. One application of 150 pounds of nitrate of soda about four weeks after planting, and the same amount when head formation begins, generally increases the yield. It is not necessary to distribute this fertilizer around the plants or along the rows, but it may be applied broadcast by hand as clover seed is sown. The results are often marked, especially when used on moderately fertile soils before rain and after a long period of drouth.

It is universally conceded that stable manures are the best fertilizers for cabbage. They may be used with the greatest freedom, profits generally being largest from the most liberal applications. Henderson recommends not less than 75 tons of manure an acre. Comparatively few growers, however, can use it so lavishly for this crop; 10 to 25 tons an acre is the usual application. Of course, it should be spread before plowing, while fine manure can be disked in after plowing with better results.

355. Planting Distances

The proper distance between plants depends upon the variety, purpose of the crop, fertility of the soil, and methods of cultivating, spraying and harvesting. Early varieties, as Jersey Wakefield, may be planted 14 x 26 inches or even closer; Charleston Wakefield, 16 x 28; Early Summer and Succession, 18 x 28; Danish Ball Head, 18 x 30; Flat Dutch and other late flat-headed varieties, 24 x 36 inches. Close planting is conducive to small heads, which are often preferred by consumers. If sold by the head, and if the heads are large enough to meet market requirements, a maximum number to the acre will of course secure largest returns. The richer the soil the closer the plants may be set and still get heads of marketable size. Close planting, however, prohibits cultivation late in the season, which is very important in dry weather. It may also prevent the use of power sprayers, and of carts or wagons when harvesting the crop. Yields by weight are larger when distances are medium rather than close. The most approved plan is to plant rather close in the row and allow a liberal space between rows. Some of the most successful growers prefer planting in check rows because of advantages in cultivating, and because less hoeing is required than in the usual method.