Effects of too much Potassium?
I own a yard that has been basically neglected (by me) for the last five years up until last Fall, and based on what it looked like when I first moved in, quite a bit longer than that.
Last Fall I renovated (Round-Up, new seed, some starter fert) and this year I would like to encourage it further. But I am wondering if I am putting down too much Potassium. After five years of doing virtually nothing, with my new seeding last Fall I put down a starter fertilizer in quantities that resulted in 1.2 lbs. Potassium per thousand feet.
This year I have already put down one pound of Potassium per 1,000 square feet, between a half-application of fall fertilizer that should have gone down (at twice that amount) in November, and the Potassium content of the "Double-O-Seven" Dimension product by Lesco.
I am wondering two things: first, can this amount of Potassium hurt my grass? Reading around I thing the answer is "no," but I'd really appreciate some expert opinion on that.
Second, how does an excess of Potassium in the soil hurt the environment, if at all? This is important to me mainly because my storm sewers run maybe a thousand feet before emptying into the Long Island Sound.
I know the best way to determine Potassium content in my soil is with a soil test, and after my recent amendments have "soaked in" awhile I plan to get one. But given the many previous years of total neglect of this lawn, I am thinking that I may not be very far from optimal at this point, but would very much appreciate hearing your opinions.