Ten plant extracts were used to select effective organic components against four major asparagus fungal diseases caused by Poitrasia circinans, Botrytis cinerea, Fusarium oxysporum, and Stemphylium vesicarium. Primary screening results using the disk diffusion method revealed antifungal effects of the extracts of cloves, mixed extracts of coptis chinesis and rhubarb, and grapefruit seed, bower actinidia, and purple coneflower. The extracts of cloves and grapefruit + Dahlia + chrysanthemum showed about 79.4% and 78.2% inhibition P. circinans growth at low concentrations of 500 ppm, respectively. Clove extracts were the most effective against B. cinerea and F. oxysporum at 500 ppm, with 86.2% and 59.7% reduction in growth, respectively. S. vesicarium was found to be effectively inhibited by about 80% at 500 ppm by all the four plant extracts. The grapefruit seed + bower actinidia + purple coneflower extract reduced P. circinans conidiation by 89.0% at 500 ppm. Clove extract showed an excellent reduction in F. oxysporum conidiation by 94.3% at 500 ppm. These results provide basic data for biologically controlling major fungal diseases of asparagus using plant extracts.