CFL for seedlings


I’m starting 2 auto seedlings in solo cups so I need a consistent and decent indoor lighting source to veg them a couple of weeks before moving outside for the grow. My indoor tent is packed full plus the QB power driver is set to high output for mature plants. This is forcing me to get the seedlings started elsewhere.

I have a desk lamp with a flexible neck that be adjusted easily for height. I found some CFL bulbs at Lowes that are 100 watt equivalent but only draw 23 watts at the wall. The color temperature is 5000k daylight.

I will only use this CFL for a couple of weeks until the leaves reach the cup’s rim, then I’ll up-plant one time and harden the plants off for the outdoor grow.

My question is - Will the CFL bulb I described do the job to get the plant up and running? I don’t want to spend a ton of money on something as short term as this will be used.


One bulb will be fine to do 2 plants in Solo cups. It will have just enough light and spread. I would recommend getting 6500K bulbs instead of 5000K though, if your store has them. Keep the bulb about 5 inches above the plants.


Cfls are great for the seedling stage.
I use a clear cup over the seedlings as a humidity dome, and the cfl hung just a few inches above them.


Thank you for the thumbs up on the CFL’s. I went ahead and bought the 5000K at Lowes since that’s the best I could find locally, then I found the 6500K’s (@TommyBahama) on Amazon and ordered a 4 pack of them. They’ll be in on Tu and I can do a swap out. Luckily, they are not expensive at all, so this is a very easy solution to veg the seedlings for a short time.


i use cfl bulbs for seedlings and early veg. I will say that at 2 weeks old, they will need a bulb per plant. and at 5 weeks, 2 bulbs per plant.


My seedlings have their cotyledons of course, plus they have their first set of true leaves. I figure in 2 weeks their first set of true leaves will probably have reached the outer rim of the solo cup and be ready to move on up. Once they go into a larger pot, they will move outside for a hardening off period. All in all, I project a 2 or 2.5 week stay under the CFL’s. Auto plants move into flower so quickly I don’t want to stunt them by lagging behind.


It will be sufficient for a couple of weeks. NOT ideal, but will work. I use a 125w (actual wattage) CFL bulb for my seedlings. Yours is 23w.


Totally agree - NOT ideal but will work better than nothing. Since this is a temporary situation, I hesitate to buy expensive products for a 2 week span.

In fact, once my current tent has finished a photo grow, I’ll be putting up a larger tent which I have in waiting. Then this current tent will become a nursery so my seedling problems will be solved at that point. This is why I didn’t want to spend much on a temporary light source.


@Grandaddy013 like this one buddy?? And you you use a cfl reflector right?

Bulb like that, and I don’t have a reflector. I will get a picture when I go over there today

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Sweet… thanks! @Grandaddy013

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Do NOT get the one for mogul socket.