White Bluffs spokesman. [volume] (White Bluffs, Wash.) 1907-1938, 1933-08-03
Inquiries Concerning
Lettuce Fertilization
(By County Agent E. c. Durdle)

Several requests have been made to
the county agent for information on
fertilization of fall lettuce. In the first
place we may say that to date there has
been little evidence to show that any
other element of fertilizer is needed
than nitrogen and PHOSPHORUS. Result
at the Experiment Station at Prosser
indicates that manure>is the best fert-
ilizer from the standpoint of weight
of heads. This probably is due to the
fact that we have in the manner slow
acting fertilizer rather than something
that is Immediately available as well
as material that assists in improving
of the physical condition of the soil.
It has been the general recommended
ton for a number Of years that ground
on which good cover crop has been
turned under or on to which a heavy
application of manure has been made
for an early potato crop makes an ideal
soil for fall lettuce. There seems to be
no reason for changing this general
recommendation.
When it comes to the application of
commercial fertilizer, however, one
would have to add enormous quantities
of commercial to do much toward i'm
proving the physical condition Of the
soil. This would be such a large
amount that the cost would be entirely
beyond returns secured. From the
standpoint of results secured from add
ing various elements of commercial
fertilizers results show that nitrogen is
the principal limited factor but that on
! some of the older soils there is ten
dency to produce a soft head while the
| phosphates when added with 1t seem to
| increase the hardness of the head.
| AS to the amounts to apply this will
| depend upon the past cropping history
| the soil. New soils or those having had
a fair to good application Of manure
should not need more than two to three
hundred pounds of ammonium sui
plate per acre in order to supply suf-
fcent nitrogen. On older soils or those
hacking manure applications it may be
necessary to apply up to five or six
hundred pounds. From one-half to two
thirds of the nitrogen may be applied
at the time the soil is plowed and the
balance used as a side dressing after
the crop gets we'll started. This method
of applying the fertilizer will also en-
able the grower partly to determine
just what his ultimate needs may be.
In regard to the phosphates, if soil
has been farmed for longer period
than to 10 years we would suggest the
application Of 100 pounds of super
phosphates on one fifth of an acre and
then carefully observing results at har-
vest time to determine whether this
| phosphate has improved the crop by
increasing the firmness of the head. II
there seems to be no difference between
the nitrogen and phosphate and the nj
trogen alone in this we would seriously
question whether it might be worth
while to apply phosphates even another
year in this quantity over the entire
field. This amount will provide practic.
ally 80 pounds of phosphoric acid to thu
acre and we believe should be sufficien
for soils in this area.
We still have available few bulle
, tins as prepared by a Soils and Ferti
/ lizer Council Meeting at Yakima las
year. These give general fertilize
, recommendation for crops in this are:
2 and we would be glad to hand or mai
3 these out to anyone interested. TIL
5 question of fertility is one to be an
J, severed for each farmer and should b
0 based upon past history of the field an
1 we shall be glad to try to answer per
sonay questions for interested.