Answer: If your seedlings are spindly, they're not getting quite enough light. To grow compact seedlings with strong stems you'll need to improve the source of artificial light (or add some supplemental light if you're relying on natural light). Use gro-lights or fluorescent shop lights to provide light to your seedlings. Keep fluorescent tubes only 2"-4" above the tops of the foliage, and keep them on 14-16 hours each day, turning them out at night.
Hope your next crop of seedlings are hale and hardy!
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