Disclosed are embodiments of a method of using mustard meal or mustard meal extract. Certain embodiments concern controlling vegetable sprouting, such as potato sprouting. Vegetables, such as potatoes, may be exposed to products resulting from mustard meal, or an extract thereof, contacting water. Other embodiments concern a process for controlling plant pests, such as insects, nematodes, fungi, weeds, and combinations thereof, with specific embodiments being particularly useful for weed suppression. Certain embodiments comprises extracting glucosinolates from plant material, or processed plant material, selected from the family Brassicaceae, particularly from the genera Brassica and Sinapis. Extracted glucosinolates can be hydrolyzed to form active compounds, or alternatively, they can be hydrolyzed in situ, by applying simultaneously or sequentially applying myrosinase. The extract can be applied to plants, to the soil adjacent to the plant.
