Veg to flower light change

should the light change (indoor) be gradual or abrupt? will going from 18/6 to 12/12 be a shock to the plants… or is that the whole point of ‘forcing’ flowering… or should I change the light schedule in increments of an hour or 2 over a weeks time???

Straight to 12/12 will not cause any real negative problem to the plants, I don’t really know of anyone that goes to all the trouble to slowly incrementally change the light cycle.

I actually do; I generally grow from seed using 6-8 hours of deak photo period. At some point, depending on when I plan to flower the plant; I decrease the photo period “on” time by an hour a week, until I get to 12/12.

Here is a schedule if you want to try it. This will have no adverse effect on your yield, and will allow the plants to stretch throughout the Vegetative photo period; Causing less stress and "stretch after inducing the 12/12 photo period.

Great for clones and seedlings. start at 18/6 photo period “Pp”; Flower week 8
Week 1, and 2 - 18/6
wk3 17/9
wk4 16/8
wk5 15/9
wk6 14/10
wk7 13/11
wk8 12/12

So say I want to flower after 8 weeks. I start at 16/8, for 4 weeks.(I do this to promote female plants)
week 5 - 15/9
week 6 - 14/10
week 7 - 13/11
week 8 -12/12

Have fun. I hope this helps. lw

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