If you have a stem from a head of romaine lettuce that's still intact, place the stump in a bowl with about ½ inch of water and put it on a windowsill. You'll start to see new leaves in about 2 weeks, and they'll be full grown in 3 to
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amazing thing about lettuce, is that if the stump is intact it will regenerate and regrow new shoots for a second harvest. Put each stump in a half inch of water, check the level daily, and wait for tender new growth.
Vegetables you can regrow again and again Romaine Lettuce Put romaine lettuce stumps in a inch of water. Re-water to keep water level at inch. After a few days, roots and new leaves will appear and you can transplant it into soil.