Abstract <p>The use of raw plant materials and plant products has been traditionally used to treat or prevent many diseases since ancient times. Recovery of plant residues is very valuable and economically efficient. <i>Lavandula angustifolia</i> Mill. is one of the most important medicinal plants of the Lamiaceae family, and local healers use its essential oil, infusion, and decoction to improve rheumatic and nervous pains and heal wounds. The present study was designed for the first time in Iran with the aim of comparing the efficiency (yield), quality (chemical composition), and antibacterial activity of essential oils and various extracts obtained from waste oil extraction equipment from three different cultivation areas. For this purpose, the flowering branches, in June 2022, at the same time as the flowers open, were collected from three different cultivation areas of Golestan (Azad Shahr—Kouhmiyan village), Markazi (Delijan city – Mahdi abad village) and Fars (Firouz abad city -Ahmad abad village). After extracting the essential oil by distillation with water (Clevenger apparatus), water extract and ethanol extract were extracted from residues of the material inside the balloon. The chemical composition of the essential oil was identified by a chromatograph coupled with a mass spectrometer (GC–MS). To evaluate the antibacterial activity of essential oil and extracts against different wound-causing strains was used the method of determining the diameter of growth inhibition zone (GIZ) and the minimum inhibition concentration (MIC), and the minimum bactericidal concentration (MBC). The results showed that the highest essential oil yield belonged to the area of Delijan- Mahdi abad village (4.5300 ± 0.8789%). Based on the results linalool (28.21–92.95%), eucalyptol (15–31%), linalyl acetate (12.2–2.16%), borneol (13.31–0%) and caryophyllene oxide (6.27–0.77%) were the dominant compounds of this essential oil in different cultivation areas. The largest diameter of growth inhibition zone by ethanolic extract of the residual herb of Azad Shahr- Kouhmiyan village was against <i>Staphylococcus aureus</i> bacteria (9.5 mm), which was twice weaker compared to rifampin (21 mm). The strongest inhibitory activity belonged to the ethanolic extract of Azad Shahr- Kouhmiyan village with a MIC value of 15.63 µg/mL against Gram-negative bacteria <i>Proteus mirabilis</i>, which had worked equal to rifampin (MIC = 15.63 µg/mL) and one times stronger than gentamicin (MIC = 31.25 µg/mL). Therefore, it is possible to obtain some by-products from plant waste (residual water &amp; residual herbs) resulting from the extraction of the essential oil of this species. It can be a possible natural option to inhibit some microbial strains that cause skin wounds, which requires clinical studies and further research in the future.</p> Graphical abstract <p></p>