Answer: In general, the larger a seedling is before you set it in its permanent place in the garden, the more "transplant shock" it suffers. Also, plants grown indoors under fluorescent lights just don't get the light intensity they need to flourish,though it's fine for starting them off. With tomatoes, for example, you'll probably find that plants you started indoors 10 weeks before setting out will produce fruit at about the same time as ones you start 6 weeks before. Once they are out in full sun, the younger plants quickly catch up. This past season, I started several nasturtium plants indoors, and direct-seeded some in the garden. The direct-seeded ones grew much faster and flowered sooner than the ones I started indoors. I think the handling during transplanting set them back.
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