Answer: Pinching them back to soil level will surely kill the little guys! They need at least two (and preferrably 3-4) sets of true leaves to manufacture food for the plants and to provide places on the stem for new buds to develop. To keep them from getting too leggy keep the gro-lights only 2" above the tops of the plants and lower the daytime temperature. After they've developed 3-4 sets of leaves pinch back the growing tip to encourage additional side growth. It takes patience to grow sturdy, bushy transplants but your patience and TLC will be rewarded when your impatiens begin to flower!
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