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seedlings under ights

Posted by gdr41 pa. z6 (My Page) on
Fri, Dec 16, 05 at 20:39

I have some trays of bamboo seedlings under fluorescent shop lights.trays about 12 inches under lights.could someone tell me how long I should leave the lights on each day.The seedlings seem to have stopped growing at about 4 inches.I've only been running lights 8 to 10 hours.

Follow-Up Postings:

RE: seedlings under ights

Hi gdr41,
I'm not sure about bamboo but vegies I start indoor I'll leave under the fluors 24/7 until there ready to go under the big light. You might also consider getting the light closer too.

RE: seedlings under ights


For most plants I set my timers to leave my lights on for 16 hours and off for 8 hours. Many plants actually need a dark period for proper functioning. However the length of the needed light period and dark period depends on the photoperiodic responses of that plant variety.

For some plants the critical factor is day length and for others the critical factor is night length. You might want to Google search to find the light preferences of your bamboo seedlings. They might benefit from overdriving your fluorescent fixtures, so that your bamboo seedlings receive more foot candles of light when the fixtures are on.

Ambient temperature could be a factor. Another factor is the volume of growing medium that is available to each plant. Maybe your pots aren't big enough and your plants have become severely rootbound. Nutrition is another factor.


RE: seedlings under ights

  • Posted by gdr41 pa. z6 (My Page) on
    Sat, Dec 17, 05 at 17:48

Trays should have enough space.I set the timer to 16 hours today.I'll see if I get any growththis week.

RE: seedlings under ights

  • Posted by DanaNY z6 Brooklyn, NY (My Page) on
    Mon, Dec 19, 05 at 22:14

I'm not sure about bamboo either, but I agree with everything MarineMan said. I keep my lights on for 16 hours, 8 hours off at night and only adjust it for the daylight sensitive plants that need longer or shorter daylight hours. If you haven't started fertilizing yet, you can start once they have 1-2 sets of true leaves.

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