r to insure that the
crop is supplied with nitrogen, phosphates, and potash.

==Nitrogenous manures== specially stimulate the growth of the foliage,
stems, and roots of plants, and are therefore of the greatest benefit to
Carrots, Parsnips, Turnips, Beet, Celery, Asparagus, Rhubarb, all the
Cabbage tribe, and leafy crops generally.

=Nitrate of soda= supplies the single plant food-element, nitrogen, and
the soda for all practical purposes may be disregarded. It dissolves
very easily in water and is taken up immediately by growing plants, its
effect being plainly seen a few days after application. As this
artificial readily drains away from uncropped land it should only be
administered to growing plants. It is best applied in spring and summer
and in small quantities; for example, at the rate of one pound per
square rod, repeated at intervals of two or three weeks, rather than in
a single large dose. Nitrate of soda must not be mixed with
superphosphate, but it may be added to basic slag and the potash
manures.

=Sulphate of ammonia= is another nitrogenous fertiliser, similar in its
effects to nitrate of soda, but slower in action since its nitrogen must
undergo a change into nitrate before it is available for plants. It is
held by the soil, and can therefore be applied earlier in spring than
nitrate of soda without fear of loss. The continued use of this manure,
however, is liable to make the soil sour, and consequently it should
only be employed on ground containing lime, or to which lime has been
added. Never mix sulphate of ammonia with basic slag or with lime, but
it may be mixed with superphosphate and the potash manures.

==Phosphatic manures== have the opposite effect to the nitrogenous
fertilisers, checking rampant growth and encouraging the early
formation of flowers, fruit, and seeds. They are comparatively
inexpensive and should be liberally applied to all soils for all crops.
=Superphosphate= is an acid manure and best suited for use on soils
containing lime. =Basic slag= is a better material for ground deficient
in lime, or where 'club-root' is prevalent. It is less soluble and
therefore slower in action than superphosphate. Both these fertilisers
should be dug into the soil some time before the crop is planted or seed
sown--superphosphate at the rate of two to three pounds per square rod;
basic slag in larger amount, five to six pounds per square rod.
Superphosphate may also be employed as a top-dressi