This study aims to reveal the effects of out-of-class learning activities conducted in the school garden on students' interest in science and their scientific attitudes. Research designed as a pretest-posttest control group quasi-experimental design of quantitative research methods. The research group of the study consists of 37, 7th grade students enrolled in a public school in Turkiye. Reproduction, growth and development in plants were conducted through school garden-based science activities for seven weeks. The research data were collected using Science Interest Scale and Scientific Attitude Scale. The study findings showed that garden-based activities have a moderate and close to moderate effect on students' interests in science and scientific attitudes. As per these findings, we can say that school gardens are out-of-class learning environments that can be used to help increase students' interest and attitudes toward science.