HOW TO GROW ONIONS 
Plant the best seed obtainable as cost is small compared with 
results. 1 oz. to 100 feet of drill, three to five pounds per acre, 
except Sweet Spanish and like sorts, 174 to 22 pounds. 
For sets, forty to eighty pounds per acre. 
THE SOIL 
A crop of onions can be grown on any soil which will produce 
a full crop of corn, but on a stiff clay, very light sand _or gravel 
neither a large nor a very profitable crop can be grown. We prefer 
a rich loam with a slight mixture of clay. This is much better if 
it has been cultivated with hoed crops, kept clean from weeds and 
well-manured for two years previous, because if a sufficient quan- 
tity of manure to raise an ordinary soil to a proper degree of 
fertility is applied at oncé, it is likely to make the onion soft. 
The same result will follow if sown on rank, mucky ground or on 
that which is too wet. 
FERTILIZING 
There is no crop in which liberal use of manure is more essen- 
tial and it should be well rotted. Rank, fresh manure is liable to 
result in soft bulbs with many scallions. See your county agent 
or some successful onion grower or fertilizer distributor for amount 
and kind of commercial fertilizer to use. 
PREPARATION 
Refer to page 4 for preparation of the soil. 
SOWING THE SEED 
This should be done as soon as the ground can be made ready. 
Here at Rocky Ford we plant from Feb. 20 to April 1. A good 
hand seed drill will do an excellent job of planting. Growers of 
large acreages here plant with the 4 and 6 row beet drills, using 
special plates. This permits cultivating with tractor cultivators. 
The drill should be carefully adjusted to sow the desired quan- 
tity of seed about one inch deep. The quantity needed will vary 
with the soil, the seed used and the kind of onions desired. Thin 
seeding gives much larger onions than thick seeding. Two to 
two and one-fourth pounds of seeds per acre is sufficent for very 
large sorts like Sweet Spanish and as much as five or six pounds 
per acre can be sown of the smaller sorts. Use a drill with a 
roller attached, but if the drill has none, the ground should be 
well rolled with a light roller immediately after the seed is 
planted. It is impossible to cultivate the crop economically unless 
the rows are straight. 12 seeds planted per foot of row requires 
about 1% lbs. to 2 lbs. per acre. 
CULTIVATION 
As soon as the onions are large enough so that the rows can 
be seen, begin cultivating very shallow and as close to the rows 
as possible without damaging the plants. Cultivate every week 
to ten days until the bulbs have started to develop. 
Here a special weeder made from clock spring with handle, is 
used for removing grass and weeds from the row (listed page 
73). Do not cover the onions with soil when hoeing or cultivating. 
If under irrigation, irrigate every week to 10 days, until the 
crop is matured or up to about 10 days before harvest. Here we 
irrigate 12 to 14 times and cultivate 10 to 12 times. 
Furrows must be large enough to irrigate without flooding. 
Flooded onions will not bulb properly. 
GATHERING 
As soon as the tops die in the fall, the bulbs should be pulled 
and about four rows put together in each windrow. As soon as 
the tops are dried, cut about one-half inch from the bulb with 
shears and put into field crates. Stack crates in piles of about 
one truckload each and protect top crates from weather, When 
thoroughly cured, run over grader, sort out scallions and dam- 
aged bulbs and store in onion house. Stack so that the best of 
ventilation is assured. Keep dry and as near a uniform temper- 
ature just above 32 degrees as is possible. Repeated freezing and 
thawing will spoil the bulbs. Moving frozen onions will ruin 
them. Wait until thawed if caught by freeze. Very early onions 
are grown by the transplanting method, the seed being sown in 
frames or beds, and the small onions transplanted when the size 
of a small lead pencil, to the field rows, 
The tops of some Sweet Spanish Onions remain green right up 
until time it is necessary to harvest. The onions may then be 
pulled and allowed to remain in windrows long enough for drying 
down the tops. 
Special Onion Weeders listed page 73 
50 D. V. Burrell Seed Growers Co., Rocky Ford, Colo. 
