352 JOUKNAL OF THE KOYAL HOETICULTUEAL SOCIETY. 
fertiliser and the remainder of the salt of potash in July ; the other half 
of the nitrogenous fertiliser, together with 400 to 500 kilos. (882 to 
1,102 lb.) of gypsum, in September ; and ten or twelve days after the 
sulphate of iron. The gypsum and the sulphate of iron tend to fix the 
fruit on the tree, and at the same time, by repressing the excessive growth 
of the wood and leaf, direct a great part of the fertilising elements which 
might have been monopolised there to the fruit. 
If it is desired to hasten the ripening, the application of the fertiliser? 
usually done in June, should be done at the end of May. 
It should be remembered that it is not by the use of a greater quantity 
of manure that one obtains a larger crop, because as soon as ever you pass 
the limits which the plant can healthfully assimilate (which are approxi- 
mately the quantities mentioned in the foregoing formulae, and more 
exactly those indicated by a chemical analysis of the soil), the excess that 
we use will not by any manner of means produce the desired result. 
The Lemon, Citeon, Bergamot, and Lime. 
All the trees comprised in the Citrus group have, with slight variations, 
the same plant-food requirements ; all of them prefer a sweet friable soil 
of good depth, and moist without being wet. 
The Lemon and the Citron require more manure than the other Citrus 
trees ; then follow the Sweet Orange, the Bergamot, the Sour Orange, and 
the Lime. 
In all cases it is necessary to use manures in the same way as 
described for the Orange, the only modification being to make an 
increase of 10 to 12 per cent, in the quantity of nitrogenous fertiliser, 
because the Lemon, Citron, Bergamot, and Lime, and even the Sour 
Orange, require under equal circumstances a greater quantity of nitrogen 
than the Sweet Orange. 
