COMMERCIAL FERTILIZERS FOR ONIONS.* 

W. H. JORDAN AND F. A. SIRRINE. 
SUMMARY. 
(1) Experiments in the use of different quantities of a com- 
plete fertilizer in growing onions were conducted at Florida, 
Orange county, N. Y., for four years on the same field and for 
one year on a field of another farm. 
(2) The quantities of fertilizer used were 0, 500 Ibs., 1000 Ibs., 
1500 lbs. and 2000 lbs. per acre. 
(3) On the Purdy field (four years), when only 500 Ibs. of fer- 
tilizer was used, the manure cost of the increase of crop was 
16.6 cts. per barrel; with 1000 Ibs., 79.3 cts.; with 1500 lbs., 80.4 
cts., and with 2000 lbs., 227.8 cts. 
(4) The profit from using the fertilizer came mostly from the 
first 500 Ibs. applied, averaging $35.84 per acre. With onions 
at $1.25 per barrel the profit was slightly larger (about $3 per 
acre) with both the 1000 lbs. and 1500 lbs. of fertilizer per 
acre; but 2000 lbs. was used at a loss. 
(5) On the Mars field one experiment was conducted which 
showed no increase of yield from applying commercial fertilizer 
,cven in the larger quantities. 
(6) The results of these experiments show clearly that the 
crops were limited more by other conditions than by the extent 
of the plant-food supply. With the best conditions of season 
and water supply the smallest amount of fertilizer supported 
the maximum crop. . 

*A reprint of Bulletin No. 206. 
