Wheatgrass is highly susceptible to mold. Its seed often contains mold spores. And because of its close-growing habit, wheatgrass often develops mold as it grows. The most common type of mold that grows is blue or green mold, which only grows on the surface and is nonpathogenic. Simply cut the wheatgrass above the mold and rinse it thoroughly before you juice it. But to prevent mold from cropping up in the first place, treat the seed and the growing plant with food-grade hydrogen peroxide.
Soak the seeds in hydrogen peroxide for five minutes to kill any mold spores that may be growing on the seeds.
Spray the growing wheatgrass with hydrogen peroxide once weekly to kill any mold spores that are growing on the grass.
Rinse the wheatgrass before juicing it.
Throw out any wheatgrass that has developed white or brown mold that is killing the plant. This mold is pathogenic. Destroy the plant and wash the seed tray with bleach before growing a new crop.