Join Date: Jan 2013
Location: South Central MN
Mentioned: 0 Post(s)
Quoted: 160 Post(s)
From the rate you mentioned I would guess the liquid was applied in furrow?
The plant still needs its P to come from somewhere. Liquid fertilizer in furrow or slightly to the side (like 2X2 placement) is accessed by the plant quicker and easier but for the most part is only intended to get the plants off to a good start. Depending on conditions may not need as much, due to some of the P not getting tied up by something else since it is in a band close to the root system, but no way could you cut the rate used by a large amount and have it work out long term.
You may see your biggest yield results from broadcasting a little lower amount of P with the other fertilizers and putting on the remainder with the planter, but some years the economics won't be favorable for that route either. The response will also depend on the P levels in your soils, if they are low then the liquid should have a high response %, otherwise if they are on the high end might not need a lot and the liquid starter might not do a whole lot. I put down 5 gal. of 10-34-0 per acre using a 2X2 fertilizer opener on the planter for corn, and the remainder was broadcast. (One highly variable field had P applied variable rate, ranged from 0 to 40+ units per acre of P, but put the liquid on every acre. Time will tell when/if I see much response.)