Tomato plants grow best when the temperature is around 70 °F (21 °C), so make sure your home temperature is near that.
Row covers are a better choice for this method because they’re designed to keep plants warm. Buy them at garden stores or online. Take the covering off during the day so the plants get sunlight. This method also works if there is an unexpected early frost, but the weather is supposed to warm up afterward.
Shake off all the dirt and debris from the plant so it doesn’t make a mess in your home. If any tomatoes fall off while you’re pulling the plant up, ripen them in a bag or box.
For the simplest solution, tie a string to a nail in your ceiling rafter. Then tie the string around the base of the plant and leave it hanging upside down. You can also punch a hole in the bottom of a bucket. Then tuck the plant through that hole and suspend the bucket from the ceiling. Place a sheet or pan beneath the plant to catch any falling dirt and leaves.
Leave the stem attached on all the tomatoes you pick. This helps them ripen better.
Make sure the tomatoes are dry because mold grows best in moist environments.
If you have a lot of tomatoes to ripen, use multiple boxes or bags. Too many tomatoes in one place will eat up all the ethylene, the chemical that makes plants ripen.
Use a banana that is still slightly underripe and still has green ends. A brown banana won’t produce anymore ethylene. If you place the tomatoes in multiple containers, add a banana to each one.
Don’t make the container airtight or too tight to open. You’ll still have to check every day for signs of rotting, bruising, or mold growth, so make sure you can open the container easily.
In warmer environments, around 65–70 °F (18–21 °C), the ripening process takes 1-2 weeks. In cooler environments, the process takes closer to a month. Use the ripe tomatoes within a week of removing them for optimal taste and freshness. If you won’t use them right away, place them on a windowsill in direct sunlight.
