Md. Code Ann., Agric. § 6-213
The plant nutrient content of each commercial fertilizer shall remain uniform for the period of registration. No percentage of any guaranteed plant nutrient element may be changed in a manner that lowers the crop-producing quality of the commercial fertilizer, even if the fertilizer is registered subsequently.
Added by Acts 1973, 1st Sp. Sess., c. 6, § 1.
Formerly Art. 66C, § 474.