How close is too close you ask?

[Camaro1691]

I’ve recently been asked by a couple people, how close can you have florescent lights without harming your seedlings/miniature plants? Well, here is where I typically set my light till I’m ready to switch to blurple, I don’t use a tape measure to set it perfectly, I use the back side of my hand and to be honest, these bulbs are cool enough, I’ve allowed plants to grow right up between the bulbs with no issue. As a general rule of thumb though, I go by the hand measurement and the 2 finger standard. Under 24 hours light the lights typically need to be raised every 3 days due to such rapid plant growth

 

[Cannamusic]

Yeah - I was gonna say the old back of the hand test, but you covered that point.

 

[Camaro1691]

I don’t know that there is such thing as too close with a florescent, in my years growing I’ve always let the plants start to grow between the bulbs before I raise them, once I start getting closer to 12” away from the seedlings, they seem to want to stretch like crazy yet are not quite ready for the bigger lights, I typically go 24/7 for minimum of 2 weeks then I start to dial my timer back an hour each week and switch to the blurples at that point