Illinois Statutes Chapter 415. Environmental Safety § 65/5a. Fertilizer; application restrictions

(1) Apply phosphorus-containing fertilizer to a lawn, except as demonstrated to be necessary by a soil test that establishes that the soil is lacking in phosphorous when compared against the standard established by the University of Illinois. The soil test required under this paragraph (1) shall be conducted no more than 36 months before the intended application of the fertilizer and by a soil testing laboratory that has been identified by the University of Illinois as an acceptable laboratory for soil testing. However, a soil test shall not be required under this paragraph (1) if the fertilizer to be applied is a 0% phosphate fertilizer or the fertilizer is being applied to establish a lawn in the first 2 growing seasons.

(2) Apply fertilizer to an impervious surface, except where the application is inadvertent and fertilizer is swept or blown back into the target area or returned to either its original or another appropriate container for reuse.

(3) Apply fertilizer using a spray, drop, or rotary spreader with a deflector within a 3 foot buffer of any water body, except that when this equipment is not used, fertilizer may not be applied within a 15 foot buffer of any water body.

(4) Apply fertilizer at any time when the lawn is frozen or saturated. For the purposes of this paragraph (4), a lawn is frozen when its root system is frozen (typically 3 or 4 inches down), and a lawn is saturated when it bears ample evidence of being or having been inundated by standing water.