Answer: When seedlings become leggy it's usually because light levels are too low, even under greenhouse conditions. You can keep your seedlings short and stout by supplementing natural daylight with fluorescent lighting, kept about 2" above the tops of the plants. Lights should remain on 12-14 hours each day. After your alyssum have developed 3-4 sets of true leaves you can pinch them back to promote bushy growth. Feed regularly, provide adequate light and warm daytime temperatures, and your plants should be as robust as those you find in nurseries.
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