To produce high yield, quality crops of mushrooms is an important component of the mushroom industry. The present study, was carried out to evaluate the effect of seven vegetable materials (two commercial neem-based products, Neemazal-T/S (R) and Greeneem oil (R), containing azadirachtin-A, and five hot water extracts from plants: Inula viscosa L., Ononis natrix L., Origanum onites L., Pimpinella anisum L. and Teucrium divericatum Sieber) on the yield and productivity of white button mushroom, Agaricus bisporus (Large) Imbach. The concentration used was 5ml.l(-1) water for the neem products, and 50g.l(-1) dried material in water for the plant extracts tested. Dilute sprays of all the materials tested (150ml per bag, corresponding to 1200ml.m(-2)) were applied by soil drench to the casing layer using handgun sprayers. The effect of the test materials was evaluated by yield (kg per bag) and productivity (relation between fresh mush-room, weight and fresh compost weight, as %). The applications of vegetable materials by soil drench to the casing layer had a stimulatory effect on mushroom yields. Yield increased with all vegetable treatments over the water-treated control. With the exception of O. natrix and O. onites extracts, significant productivity increases (7.7 to 21.9%) compared to the control were observed as a result of plant extract applications. The results suggest that plant materials may play art important role on the yield and productivity of A. bisporus, and may also be used in organic mushroom cultivation.