MIXING FERTILISERS.

Hauraki Plains Gazette, Volume XXXVII, Issue 4921, 4 January 1926, Page 1

MIXING FERTILISERS.

NEED TO EXERCISE CARE.

PRACTICAL ADVICE OFFERED. The Ministry i»l Agriculture in Leaflet No. 344 indicates, that, sulphate of ammonia or other ammbniacal manure must not be mixed with any manure holding free lime, such as basic slag and basic superphosphate, nor with manures containing much carbonate pf lime, such as Belgian! and Algerian phosphates. The result of making such a mixtureUs liberation of free ammonia, .the presence of which, in the air, can be detected by its pungent odour. Sulphate of ammonia may be mixed with superphosphate, bone manures, fish meal, nitrate of soda, salt, and most forms of potash. Mixtures .of sulphate of ammnoia and superphosphate, or of both of. these with salt and kaiiii.t, if not sown soon after being made, become moist anid pasty in a very damp atmosphere, or set hard on! long standing; this, however, can be obviated by including in the mixture a dry manure, such as, bone flour, fine bone meal, or castor meal to the extent of at least 1 to 20.

Nitrate of soda should not ordinarily be mixed with superphosphate or dissolved bones; not only may such a mixture result in the loss of some bf the nitrogen, but the mass is apt to become sticky and difficult, to sow. The addition of a considerable proportion of drying mai ures, such as flue bone meal or steamed bone flour, will remedy this. Nitrate of soda may be mixed with salt or any pbtaish manure without,, bad result. Superphosphate should not ordinarily he mixed with basic slag or precipitated phosphate, ais this, results in the soluble phosphate of ,the superphosphate becoming insoluble in pure water (though readily soluble in soil water) to an extent dependent upon the lime present. On the other hand bone flour and bbne meal produce no such effect unless the mixture is allowed to lie for a long time, while they produce a diy powdery mixture .with the acid manure. Nevertheless, slag and superphosphate are frequently mixed for the reason tlidt the mixture s.ows better than either ingredient alone, and because any disadvantages that superphosphate may have on. account of its acidity are removed. A.UettpC m ixture is obtained by using st’&ifthe.d ;bone flour instead of slag. ■ fS' -Q' • : ; v. > : ■