| 75 tons Fresh Horse Manure. | 50 tons Cabbage. | |
|---|---|---|
| Nitrogen | 820 lbs. | 240 lbs. |
| Potash | 795 lbs. | 630 lbs. |
| Phosphoric acid | 420 lbs. | 140 lbs. |
| Soda | 150 lbs. | 90 lbs. |
| Lime | 315 lbs. | 310 lbs. |
| Magnesia | 210 lbs. | 60 lbs. |
“That is rather an interesting table,” said the Doctor. “In the case of lime, the crop takes about all that this heavy dressing of manure supplies—but I suppose the soil is usually capable of furnishing a considerable quantity.”
“That may be so,” said the Deacon, “but all the authorities on market gardening speak of the importance of either growing cabbage on land containing lime, or else of applying lime as a manure. Quinn, who writes like a sensible man, says in his book, ‘Money in the Garden,’ ‘A top-dressing of lime every third year, thirty or forty bushels per acre, spread broadcast, and harrowed in, just before planting, pays handsomely.’”
Henderson thinks cabbage can only be grown successfully on land containing abundance of lime. He has used heavy dressings of lime on land which did not contain shells, and the result was satisfactory for a time, but he found it too expensive.
Experience seems to show that to grow large crops of perfect cabbage, the soil must be liberally furnished with manures rich in nitrogen and phosphoric acid.
In saying this, I do not overlook the fact that cabbage require a large quantity of potash. I think, however, that when large quantities of stable or barn-yard manure is used, it will rarely be found that the soil lacks potash.
What we need to grow a large crop of cabbage, is manure from well-fed animals. Such manure can rarely be purchased. Now, the difference between rich manure and ordinary stable or barnyard-manure, consists principally in this: The rich manure contains more nitrogen and phosphoric acid than the ordinary stable-manure—and it is in a more available condition.
To convert common manure into rich manure, therefore, we must add nitrogen and phosphoric acid. In other words, we must use Peruvian guano, or nitrate of soda and superphosphate, or bone-dust, or some other substance that will furnish available nitrogen and phosphoric acid.
Or it may well be, where stable-manure can be bought for $1.00 per two-horse load, that it will be cheaper to use it in larger quantity rather than to try to make it rich. In this case, however, we must endeavor to follow the cabbage by some crop that has the power of taking up the large quantity of nitrogen and other plant-food that will be left in the soil.
The cabbage needs a large supply of nitrogen in the soil, but removes comparatively little of it. We see that when 75 tons of manure is used, a crop of 50 tons of cabbage takes out of the soil less than 30 per cent of the nitrogen. And yet, if you plant cabbage on this land, the next year, without manure, you would get a small crop.