Answer: You can keep leaf lettuce growing for quite some time if you harvest the outer leaves but leave the center of the plant alone. You should be able to pull the leaves off the plant (cutting with scissors will encourage sap to drip from the cuts and the plant will end up with a stub of a leaf). I grasp an outer leaf towards the bottom near the stalk and push down while I'm tearing from one side to the other. The leaves come right off. You may have to try a few times to get the right technique (don't pull so hard you uproot the entire plant!). You may want to gently steady the plant with one hand and pull with the other.
Enjoy your lettuce!
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