Tea tree oil. Tea tree oil is among the most effective treatments for cellulitis due to its strong antimicrobial and anti-inflammatory properties. Tea tree oil comes from the melaleuca alternifolia plant, which is typically found in particular areas of Australia. This yellowish-green oil is greatly effective against a vast assortment of fungi, viruses, and bacteria. Tree tea oil is very strong and should be diluted with coconut or olive oil before applying it to the skin.