“It is very evident,” said the Deacon, “that if you grow cabbage you should make the land rich enough to produce a good crop—and I take it that is all you want to show.”
“I want to show,” I replied, “that our market gardeners have reason for applying such apparently excessive dressings of rich manure to the cabbage-crop. They find it safer to put far more manure into the land than the crop can possibly use, rather than run any risk of getting an inferior crop. An important practical question is, whether they can not grow some crop or crops after the cabbage, that can profitably take up the manure left in the soil.”
Prof. E. Wolff, in the last edition of “Praktische Düngerlehre,” gives the composition of cabbage. For the details of which, see Appendix, page 345.
From this it appears that 50 tons of cabbage contain 240 lbs. of nitrogen, and 1,600 lbs. of ash. Included in the ash is 630 lbs. of potash; 90 lbs. of soda; 310 lbs. of lime; 60 lbs. of magnesia; 140 lbs. of phosphoric acid; 240 lbs. of sulphuric acid, and 20 lbs. of silica.
Henderson, in “Gardening for Profit,” advises the application of 75 tons of stable or barn-yard manure per acre, for early cabbage. For late cabbage, after peas or early potatoes, he says about 10 tons per acre are used.
Brill, in “Farm Gardening and Seed Growing,” also makes the same distinction in regard to the quantity of manure used for early and late cabbage. He speaks of 70 to 80 tons or more, per acre, of well-rotted stable-manure as not an unusual or excessive dressing every year.
Now, according to Wolff’s table, 75 tons of fresh stable-manure, with straw, contains 820 lbs. of nitrogen; 795 lbs. of potash; 150 lbs. soda; 315 lbs. of lime; 210 lbs. of magnesia; 420 lbs. of phosphoric acid; 105 lbs. sulphuric acid; 2,655 lbs. of silica, and 60 lbs. of chlorine.
“Put the figures side by side,” said the Deacon, “so that we can compare them.”
Here they are: