The main features of the methods used in agriculture should be sustainable, human and animal friendly and harmless to the environment and natural resources. Usage of green manure instead of synthetic fertilizers are becoming prominent due to their eco-friendly effects but allelopathic interactions among the plants should be used as a criterion to select the effective green manure plants. In the research, germination and seedling growth of some green manure plants (narbon vetch, forage pea, alfalfa, and soybean) were examined through allelopathy in differently concentrated aqueous leaf extracts of three different apple cultivars which are chosen according to their harvest time (Summer Red-Early, Mondial Gala-Middle, Fuji-Late). The results showed that increasing concentrations had an inhibitory effect on the growth of green manure plants prognosticatively but stimulatory effects were also observed in different concentrations of some cultivars. Mondial Gala (MG) showed a stimulatory effect on germination of alfalfa and soybean but the slowest germination for soybean (2,97 days) was recorded at 5 % concentration of the cultivar (MG-5). Fuji (F) caused an increment only on the root growth of soybean and Summer Red (SR) stimulated the shoot growth of forage pea while it caused a decrement on the root and shoot growth of soybean. Fresh seedling weight (FSW) of forage pea primarily increased for all apple cultivars but than, a decrement observed in higher concentrations. SR increased the FSW of soybean but contrarily decreased the dry seedling weight. If apple gardens were laid out with SR and MG cultivars, alfalfa and forage pea could be used as green manure but if the gardens laid out with Fuji, forage pea, narbon vetch and soybean could be recommended as green manure plants with regard to their allelopathic interactions.