Germinating seeds under lights?

I have some peach pits that I am germinating under lights, more as experiment and something to take away some of the winter blues than anything else. How do those of you who grow under lights gauge whether your lights are too close or too far away. I noticed today that a couple of seedlings that are 2" high seem to bending away from the light as if it is too strong. Healthy looking otherwise

I think if they are exposed from sprouts to the direct lighting…i think they should be fine…Now if you take some that haven’t had good light and then put them right up against a t8…they might burn (i’ve done that to many seedlings)… the leaves will get a little crusty and then the new ones that shoot out will be adjusted to the light and be just fine…

My biggest issue with tree seedlings is they grow fast and the roots will get restricted and then you have to move them into bigger pots…all the while winter is raging outside…i small greenhouse works wonders, but then at least here, i have to move them in and out with the sunshine.

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I have them in some small root trapper bags, I will plant them in the ground come spring. Testing the grow media that I am using and the small bags as well.

I grew an oak seedling using these same methods…today its 12 foot tall/3 inch trunk and it had acorns this past summer:

Picked the acorns off the ground south of Duluth, MN on Aug of 2009…(spent fall/winter in refrig)…germinated spring of 2010…


Growing from seed, grafting is very satisfying thing to do. Wish i had more land…i’d start a forest.


I can’t speak to peaches specifically. I wonder if there may be a heat issue with the lights you are using. I’ve I’m not quick enough to adjust my cool fluorescent lights up, my trees will grow to touch the bulbs.

I am using a single T5 bulb (thats what I had on hand). I dont notice a whole lot of heat from the bulb. They havent touched the bulb 2" away is probably the closest the bulb has been.

I shoot for about 2" - 3" with my fluorescent when seedlings are small. I thought maybe you were using a sodium or something. I’ve not really had any issues with my fluorescent lights too close unless a leaf was touching a bulb for a day or so. If they are too far away, my seedlings tend to be lankier but lankiness is always somewhat of an issue with starting trees under lights.

Post a pic if you get a chance.

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Depending upon the plant and the details of your setup, keeping a balance between root/soil temps and leaf light/temps can come into play too. If the leaves are getting too much light and heat from the light, but the soil temps are too low for efficient water transport, the leaves will suffer.

Should not be an issue if you are using bottom heat, but if the room/floor temp is cold, this could be a factor.

Watch moisture when using bottom heat (and lights). Seedlings can dry out very quickly.

Elevating the lights a bit helped my current problem This is just a small experiment with 8 seedlings so I wont lose any sleep over the success or failure of it.

That’s impressive precocity from a white oak, right? Is it bur oak or maybe a bur x swamp?

Bur? The seeds look like Bur. 6 years from sprout to fruit…not bad considering the first 2 were in a pot. It tried to have multiple trunks so i’ve had to trim it back.

I"ve also got some Red Oak (from seeds i started) that are pushing 8 to 10 feet and some black walnut (which are probably the fastest growing trees i’ve seen)…i actualy had 4 black walnuts on a seedling that a squirrel must have planted a few years ago (3 or 4 years max) that i never got around to removing (neighbor has a black walnut tree).

Both photos are straight Bur oak.

When seedlings are young (photo 1) the juvenile leaves are questionable at best in many cases. Later, as they mature - they show the true traits of the species. When identifying young oak seedlings it’s best to wait several years and reevaluate.


LED here:. Trial and error. One of the disadvantages of LEDs compared to fluorescent, I think. Less uniformity in the thermal output.

I have not found a cost effective configuration of LED lights yet compared to fluorescents. If you find one please point me to it. When I say cost effective, I’m referring to purchase cost per lumen square foot. LEDs have the potential to out perform fluorescents from an energy efficiency standpoint but I have not found equivalent configurations to shop lights.

It depends I think on which LED lights you are using for the comparison. LED grow lights tend to be quite pricey. Hard for me to justify their cost over florescent. But in the last year or so there are some low cost LED shop lights out there which are priced similar to the florescent ones (Costco has some that go on sale for the same price as the typical big box 4’ regular shop light). They seem to put out considerable light, and should last many years.

These will work great for starting seeds and also garages, etc. I ordered a case with 2 friends and we did all our garages. I know someone on another forum thats using them to grow lettuce with very good results. Get the warm white if you want to use them for growing.

For one or two lights where cost is not an issue integrated LEDs may be OK, but until fixtures become reusable with replacement bulbs, I still can’t make the math work. Yes, LEDs have a long life expectancy but I’ve had quite a few fail early. I doubt it is the LEDs themselves, but something in the electronics. A 30 pack of fluorescent bulbs costs about the same as a single integrated LED shop light. It can’t be too much longer before they become the most economical choice. I’ve looked at both the Costco and the other LEDs linked last time I bought bulbs. Each time I’m ready to buy a box, I re-do the analysis to see if I’m better of re-investing in new fixtures and LEDs. I was hoping someone had come out with a conversion bulb for my existing shop light fixtures but I haven’t seen that yet. The only ones I can find like this put out about 1700 lumens verses 2900 with fluorescent bulbs.