05/29/2026
ðą Place any green tomatoes that have reached full size into a paper bag with a ripe banana. Fold the top closed. Leave at room temperature. Check in 3 to 5 days. The ethylene gas released by the banana triggers the ripening process in the tomatoes â turning them from hard and green to fully ripe and red without any heat or sunlight required.
Ethylene is the gaseous plant hormone that triggers fruit ripening in climacteric fruits â the category that includes tomatoes, bananas, avocados, and most common garden fruits. When a ripening fruit begins producing ethylene it signals to adjacent fruits on the same plant or in the same enclosed space that ripening conditions are present. The adjacent fruits respond by initiating their own ripening process â the chain reaction that causes all the fruit in a bowl to ripen simultaneously.
A ripe banana produces ethylene at a high continuous rate â placing it in an enclosed space with unripe tomatoes creates the ethylene-saturated atmosphere that triggers the tomato's ripening response without requiring the heat and light that vine-ripening uses as the trigger. The paper bag traps the ethylene around the tomatoes at the concentration needed to trigger ripening while allowing enough gas exchange to prevent the build-up of other gases that cause rotting.
This technique is most valuable at the end of the season when a killing frost is forecast and the plant must be harvested before the fruit has ripened naturally. Any full-sized green tomato â one that has reached its final size even if still entirely green â will ripen correctly using this method. Small green tomatoes that have not reached full size will not ripen and should be used green.
ðą Save this. End of season green tomatoes are not waste. They are 5 days from ripe with a banana.
ð How do you ripen end-of-season green tomatoes and which method has produced the best flavour? Tell me the variety and the method.