Moving plants outside

I live in New Hampshire and plan on transplanting some two-month-old plants outside. I’m starting the seedlings under fluorescents and giving them 18 hours of light a day. Should I reduce the number of hours of light I give them before transplanting them outside?
The Plant Tender,
New Hampshire

During the second month of growing indoors, bring the number of hours of light down to 16 or 17, so that the plants don’t start flowering when they are placed outdoors. They receive about 15.5 hours of light outside in late June. Indica, Indica hybrid, and other early-season plants are most likely to bolt. Sativas are not likely to start flowering early.

The plants may have other problems adjusting to the outdoors. They have been growing under low light conditions of fluorescents as compared to sunlight, so they are likely to get burned by the sun’s intensity and UV light. Let the plants adjust by placing them in the shade to begin with, then giving them brighter light over a week-long period.

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