Successful seed germination is crucial in many plants. Natural substances and chemicals have been used as growth enhancement tools. In the meantime, natural substances are considered environmentally friendly and cost-effective. Hence, the present study was focused on the effects of natural substances such as red rice, white rice washed water, orange coconut, green coconut, and matured coconut water on radicle development of black gram, pumpkin, rice, and maize. Twenty-five healthy sterilized seeds (85%germination rate) of the above plants were pre-soaked in 30 ml of the natural suspension for 24 hours separately at room temperature and repeated twice. Then seeds were transferred to the sterilized petri dish with moistened filter paper and mean values of length of the radicle were measured. Data were subjected to one-way analysis of variance (ANOVA) (P<0.05) followed by Tukey test. Natural substances have not affected radicle development of the tested seeds, except pumpkin, and maize after 24hours whereas in the control radicle length of these two species was 5.48 and 0.68mm, respectively. However, interestingly after 48hours, radicle formation of most tested seeds was highly accelerated by red rice and white rice washed water, except for black gram. Hence, orange coconut, green coconut, and matured coconut water have showed an inhibitory effect on root length development, except for maize at 48 hours. On the other hand, among the selected natural substances red rice and white rice washed water revealed better effects on radicle development. So, they can be used as an environmentally friendly method to stimulate the radicle development.