Grow Lights

I bought an incandescent grow-light 60 watt bulb at a hardware store for $7.72 for my indoor early starters. Although I have the grow light 3-4 inches above them, they already look a bit spindly. I watered them thoroughly today, removed the plastic cover, and put the grow light closer to them (about 2 inches above them). I am aware of the recommendation for fluorescent lights for seedlings. That will require help from my husband, who hates my gardening, so I thought I'd try the incandescent bulb first. I am puzzled as to why it doesn't provide enough lumens for a 4" square area, though. If it can't provide the light, then why do they label it 'grow light' and charge $8/bulb for it? This is all experimentation on my part, trying to see what works and what doesn't.

Wendy

 

A 60 watt bulb is way too little light to grow strong seedlings. The symptom of low light is weak, spindly seedlings. Fluorescent tubes work better. A workshop fixture with 2 48" grow lights will illuminate your trays properly if you keep the light suspended only a few inches above the seedlings.

George

 

The incandescent lights are marketed to supplement the spectrum for your established house plants. They are just not capable of providing the energy needed to feed seedlings. There is one possible improvement you could try (as an experiment, since you already have the bulb): fashion a parabolic (bowl-shaped) reflector/fixture for the bulb and set it up above your growing area. The parabolic reflector will help concentrate the light and may give you more coverage, or at least deliver better lighting to the coverage of the reflector. You don't need to buy those expensive fluorescent grow lights either. Just regular fluorescent bulbs in a 4 foot fixture will do quite nicely (I can vouch for 20 seasons getting their start this way).

Roger

 

I can vouch for Roger's comments, as I also have almost 30 years experience starting seedlings with regular fluorescent bulbs. You have to get them close, though, about a foot or the seedlings will be spindly. This year, however, I have the opportunity to do something different. The hydroponics equipment, including halogen lighting has arrived. This was purchased by TT Inc. for the hydroponics work here at TT Inc. Headquarters. When I saw the size of the halogen bulbs I just had to hook one up to see how bright it was. Geez!! The 1000 watt bulb was so bright, at about 15 feet, that you couldn't look at it - like looking directly at the sun and a big blue spot in your vision for an hour afterward! Since we won't be actually starting hydroponic growing until after the gardens are in, I plan to use one of these lights to start the seedlings. The 1000 watt unit with reflector will light an area of 64 sq. feet as bright as the noon sun. It will be really nice to be able to put healthy plants into the cold frames to get ready for planting.

Ron