Compositions and methods for increasing the efficacy of pesticidal compositions via the combination of a pesticidally active ingredient and a C6-C10 saturated aliphatic acid are described herein, including synergistic pesticidal compositions and methods for delivery of pesticidal active ingredients. Some pesticidal compositions and methods as described are directed to compositions and methods for increasing the efficacy of fungicides. Some pesticidal compositions and methods as described are directed to compositions and methods for increasing the efficacy of nematicides. Some pesticidal compositions and methods as described are directed to compositions and methods for increasing the efficacy of insecticides. Methods for enhancing the activity pesticidal active ingredients in pesticidal compositions in use are also described.
