Gardeners who have tropical style gardens may grow banana trees (Musa paradisiaca) as a type of edible landscaping. This tree grows best in warm environments, where the fruit goes from development to harvest with the least amount of fuss. The most resilient varieties, including the Darjeeling Banana (Musa sikkimens) and the Japanese Fiber Banana (Musa basjoo), thrive in U.S. Department of Agriculture plant hardiness zones 6 through 10. While many growers wonder "when are bananas ripe," estimating how long it will take for your fruit to ripen depends on a variety of conditions, including harvest timing and storage methods.
Growing: When are Bananas Ripe?
Experts recommend that bananas remain on the tree until they are about 75 percent mature. This happens within about 75 days after you see the first bundle of bananas. A good test is rubbing any remaining flowers on the tips; they should fall off easily. Harvest the bananas carefully to avoid bruising and hang them in a well-ventilated area. From tree to table, bananas ripen in about 8 days if kept around 60 degrees Fahrenheit.
On the Countertop
The ripening process for bananas follows a specific pattern. They start out green, then turn yellow with green tips, then wholly yellow, moving into yellow with brown spots and finally turning black. If you purchase green bananas from a store it takes approximately three to four days for them to fully ripen. The banana fruit becomes sweeter as it ages. Look for brown freckles on yellow skin for the best eating banana. If the bananas are already turning yellow, you can anticipate full ripening in one to two days. Bananas with completely brown skins are the sweetest for culinary purposes, reaching perfection in about five to seven days. If the banana turns black, it is no longer safe to eat.
The Right Temperature
Green bananas taken from commercial trees stored at 57 F go to sleep, slowing their ripening process. The fruits remain in the controlled environment until ready for shipment. This is the manner in which bananas go from the fields to the stores without over-ripening. If removed from heat controls, they re-awaken and ripen in three to five days, particularly if temperatures are around 70 F. If you want the bananas to last longer, store them in an area with a regulated temperature under 60 F, such as the refrigerator.
Ideal Humidity Levels
Bananas ripen best in humidity levels of 90 percent on average, especially when combined with higher heats. They also benefit from proper air circulation. While some refrigerator crisper drawers have humidity regulators, the temperature in the refrigerator will slow the ripening process even with humidity present.
Brown Paper Bag Ripening
Putting your bananas in a brown paper bag with either a tomato or apple will speed ripening. In the bag, the tomato or apple releases ethylene gas that hastes the banana's maturation, decreasing the time you have to wait to use it by about one-half. If you use this method, put small holes in the paper bag and lay out the fruit so they’re not stacked. Check their ripening progress daily.
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