Iowa Admin. Code r. 701-17.4
Prior to July 1, 1987, sales of all commercial fertilizer and agricultural limestone were exempt from tax. On and subsequent to that date, sales of commercial fertilizer and agricultural limestone are exempt from tax only if the purchaser will utilize the fertilizer or limestone for the health promotion of plants which are produced as part of agricultural production for market. See subrule 17.9(3) for characterizations of "Agricultural production" and "Plants" respectively. Plant hormones are considered to be commercial fertilizer By way of nonexclusive example, commercial fertilizer sold for application on a lawn, golf course, or cemetery would be taxable.
This rule is intended to implement Iowa Code section 422.42(3).
Iowa Admin. Code r. 701-17.4