Buy living lettuce. Usually sold as Organically, Hydroponically grown lettuce. Clip off outer leaves and use. Leave the core leaves intact. Place in a glass of filtered water for a few days in a window sill. Trim off less lively leaves. Plant in rich soil up to base of core leaves. Plant should last through many cuttings as long as you cut from the outer leaves and leave a small inner core. Love the sweet tender butter lettuce. The plastic shell makes a good seed starter atrium as shown. Enjoy!
Pam's Tactical Kitchen 
I was thinking of leaving the central part of the lettuce with root ball on my sunny window sill. Can it grow in just water?
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I really don’t know, try it, and let us know.
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yes it can it takes a few weeks but yes
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Yep. I bought some living lettuce last week and used all of it then decided to put the roots in a glass jar with some water to see what would happen. Within a couple days, leaves were blooming. I’m about to get a decent sized pot and replant it in some garden soil.
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I tried but it not live past a week in just water and did not have any new growth.
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Jessica, For best results, add some garden fertilizer if that’s all you have. Soluable powders work well if you have them but you can also add a few pellets and they will dissolve over time. You can try to dissolve them faster by soaking them in hot water, then cool the solution before placing your lettuce in it. Good luck!
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