Grow lights are expensive. Regular light bulbs are not.
This could be a great way to save money…if regular bulbs work for growing plants.
People often assume you need expensive grow lights to make up for the lack of natural light, but they’re wrong.
You can actually use regular light bulbs to grow plants indoors.
But should you use regular bulbs?
In some cases, yes; in some, no.
And when it comes to LEDs, you want to be careful. Some regular LED lights can work just fine as grow lights, but many are not suitable—see the LED section below for more.
Before we get into that, you might be asking yourself how you would know if your plants aren’t getting enough regular light and whether they need artificial light to help them out.
Believe it or not, your plants will tell you. Not literally, of course, but they will show you.
If your plants aren’t getting enough regular sunlight, they will grow tall with weak stems and the leaves will be lighter in color. New leaves will often be larger in size and the leaves on the inner part of the plant may start to turn yellow.
If your plants show these symptoms, you are going to want to get them some additional light.
The most successful light bulbs contain both blue and red wavelengths of light. The blue is especially useful for foliage growth and the red is for flowering and fruiting.
Contents
- 1 Types Of Light Bulbs Available
- 2 How To Set Up The Lighting
- 3 Regular Light Bulbs As Grow Lights: Final Thoughts
Types Of Light Bulbs Available
If you just need light for your regular houseplants, any lamp or light fixture will do.
Which one is best for you, depends on your needs (see the next section).
You do want to make sure the light you choose has the correct color temperature (explanation below in the fluorescent light section), as this drastically improves performance.
The most popular types of light bulbs to use as grow lights for indoor plants are incandescent or fluorescent bulbs, but you can also use LED lights, halogen lights and traditional horticultural grow lights, like high-pressure sodium bulbs (HPS) and metal-halide bulbs (MH). The first two are fine for small gardens; if you’re got a larger grow, LED or HPS/MH make the most sense.
If you are thinking of growing plants from seeds, you’d be best off with hanging tube fixtures that you can place directly over your plants. There are special kits available that include the fixture and reflectors.
Do Incandescent Grow Lights Work (i.e. Regular Bulbs)?
Incandescent lights are the standard light bulbs we all already have in our homes (here are a bunch of examples on Amazon).
They are the cheapest option, but they are inefficient.
They use more power to get the same output and they give off a substantial amount of heat. For these reasons, we generally do not recommend using them for your plants.
Take a look at the following graphic.
If you do use incandescent bulbs, make sure you don’t place them too close to the plants.
Use the hand test. Place the back of your hand where the plant is and wait a minute. If the light becomes too hot for your hand, it is also too hot for the plant and you need to move it further away.
Incandescent bulbs are usually the first option people consider, because they are cheap and we all already have some lying around the house.
But we always recommend fluorescent bulbs for small first-time growers.
They don’t cost all that much more and they are a lot more efficient: they last longer and use less power, so you actually end up saving money.
Can Regular Fluorescent Bulbs Be Used As Grow Lights?
Fluorescent lights are the best choice because they are the most economical.
They are sold in tubes (like these, which are good for larger indoor gardens) or compact bulbs that go into a regular lamp socket.
These are called CFLs and are best for a few plants or as supplemental lighting. They are the bulbs we will discuss from here on (everything we say goes for tubes as well, though).
Fluorescent lamps stay cool enough that they can be placed close to your plants and they use much less power per lumen (the amount of light they give off) than incandescent bulbs, which saves you on your power bill.
Many of us also have some at home already. That said, you want to pay attention to the color temperature of the bulb to ensure the best possible performance.
If you don’t mind spending a bit more, you can get a specialized fluorescent bulb (like these) made specifically for growing plants.
These have an optimized color spectrum for plants (see the next few paragraphs to help with choosing the right color temperature) and they are also more powerful than regular fluorescent bulbs.
Regular bulbs work just fine, though, especially if your plants are already getting some natural daylight. They key is to make sure they have the correct color temperature, measured in Kelvins. Apart from that, there is no real difference between regular bulbs and grow bulbs.
How Many Kelvins Should A Bulb Have In The Vegetative Period?
Generic fluorescent bulbs and tubes are higher in blue wavelength light. This is great if you are growing plants that don’t bloom, like a cactus or herbs. It is also great for the vegetative period of blooming plants.
For growing herbs indoors, or other plants that do not bloom, use bulbs labeled as ‘daylight’ or ‘cool white’. You can also use these to veg plants that do bloom (and switch to warmer bulbs for flowering; see below). The color temperature on these bulbs will be between 6000 K and 7000 K. These are good.
How Many Kelvins For Flowering?
If you are growing plants that flower or fruit, you will want a bulb with more reddish light. You can still just use regular bulbs, but you want to make sure they are labeled as ‘warm white’ or ‘soft white’. In terms of color temperature, they will be between 2000 K and 3500 K. This is a great value pack of warm bulbs.
Another option is to get a bulb with a color temperature right in the middle, between 4500 and 5500 K (confusingly, these are also sometimes labeled as ‘daylight’). Here are good ones.
These work for all plants, but are not quite as efficient as cooler bulbs for growth or warmer bulbs for flowering. We find a mix of cold and warm bulbs to work best.
The main problem with both incandescent and fluorescent bulbs is that they aren’t generally powerful enough to flower more than a couple of plants, unless you get a ton of them. Once you get a lot of them, they are no longer cost effective, because there are much more efficient lighting options available. This article explains how many CFLs you need per plant.
If you have more than a couple of plants, you would be much better off with high-intensity discharge lights (HID) or LED lights.
Can Any LED Light Be Used As A Grow Light?
LED lights are more energy efficient and emit much lower levels of heat than other types of lighting. But can you use any kind of LED light to grow plants?
Generally, yes.
But because LED technology is so customizable, every bulb is different and you want bulbs that produce the exact mix of red, blue and other wavelengths preferred by your plants.
White light contains a great mix for plants, so white LED bulbs will work to grow. The main issue is one of power. You need lights that give you sufficient output to flower plants and many regular bulbs will not do that.
Due to the lack of power and the potential for a less-than-ideal spectrum, many general LED lights are not as effective for plants as specialized ones. That is the primary difference between led grow lights and regular led.
On the other hand, if the regular LEDs provide sufficient output and a good color spectrum (like white light), they will work just as well as a specialized grow light, since they are basically the same thing. So you can use a normal LED light as a grow light for plants.
If you are unsure and want to be certain you get a light that can both grow and flower plants, your best bet is to get a horticultural LED grow light that uses COBs. They are designed to produce the wavelengths used by plants in the ideal ratios, making them the best bloom LEDs available.
In general, you are better off purchasing these, as opposed to just general-use LED lights. They are not cheap, however. That said, there are a few quality, inexpensive LED plant lights on the market.
These are better for any type of plant. They are the best grow lights for succulents, for vegetables, for herbs, for cannabis, and for any plant, if you have more than a few of them.
Can Plants Grow Under Halogen Lights?
Halogen lights also provide full spectrum light and are quite powerful, but they are similar to incandescent bulbs in that they emit a lot of heat and are not as energy efficient as fluorescent lights, HID lights or LED lights.
HID Plant Lights
Finally, we come to traditional horticultural grow lights (if you already know you want to go with HID lighting, head here for help in choosing the best bulbs). These are often referred to as HID lights and are further broken down into HPS and MH lights.
HPS bulbs emit more of a red spectrum light, making them superior for flowering and fruiting, while MH bulbs emit more blue light, making them ideal for plant growth.
HID bulbs are very energy efficient, but because they are so powerful, they still use a lot of power and emit a lot of heat. They also require additional components like a ballast.
Since they give off a large amount of light that is powerful enough to flower any plant, HID lights are still the light of choice for most commercial indoor growers, although LED lights are slowly taking that crown (read more about HPS versus LED lights).
For most of us, HID and LED lights are far too powerful and expensive for our needs. But if you have a larger garden, you’ll definitely want to go with one of these options. If you decide on HID lights, we have a post helping you choose the best HID system for your needs.
That post covers MH and HPS lights.
These days many people are opting for ceramic metal halide instead, since these lights combine MH and HPS in one bulb. We agree that CMH bulbs are far superior.
You can read more about CMH systems here, including our recommendations for the best ones.
How To Set Up The Lighting
For a small garden of a few plants in a room with very little natural light, a standing lamp with three bulbs and a movable or goose-neck feature works well. Use fluorescent bulbs with the highest wattage allowable by the fixture for the best results.
You want to aim the light towards the table with the plants. If your light fixture does have a movable arm, place the fluorescent bulbs closer to the plants than an incandescent bulb. This is to avoid heat damage, if using incandescent light.
To make more efficient use of the bulbs, place a reflective surface, such as a mirror or just some reflective foil, underneath the plants, so that the light can reflect back up towards the foliage.
And finally, attach and set a timer to run the lights for 14 to 16 hours a day. You can do this manually, but it is easier with a timer and even a the best timers for grow lights don’t have to cost a lot.
Regular Light Bulbs As Grow Lights: Final Thoughts
You can certainly use regular light bulbs as grow lights. Light is light after all. The main thing you need to pay attention to is the color temperature. Grow light bulbs have color temperatures specifically meant for growing and flowering plants.
If you use a regular light bulb, you want to make sure it has the right color temperature. After reading this article, you should know exactly what to look for.
If you still have some questions, feel free to ask them in the comments below. If they have not already been answered in the article, we will answer them in the comments.
Sources
- http://io9.gizmodo.com/what-makes-grow-lights-different-from-the-lamps-in-your-1629188801
- http://homeguides.sfgate.com/grow-seed-inside-regular-light-bulb-96796.html
- https://growlightinfo.com/difference-between-par-and-lumen/
- http://learningandyearning.com/can-fluorescent-shop-lights-be-used-to-start-seeds
Snider says
What B.S. House hold LEDs are great for growing,. While they don’t match DIY Quantum Boards in ifficency, in this day and age growers using house hold LEDS are consistently getting over 1.4 grams/watt.
Steven says
If those household bulbs have the correct color spectrum and are powerful enough, then they could work. But the kind of LEDs most people have in their homes are not powerful enough to flower.
Bonnie guinan says
I need supplemental lighting for succulents for winter, any suggestions, don’t care if they bloom just want them to keep growing.
Steven says
The simplest would be to just get some fluorescent bulbs. There is a comment by TM further down, where he/she talks about the bulbs he/she uses for his/her succulents.
Stephen L Wertz says
You are correct LED bulbs are great for growing household plants. Evidently the writer doesn’t know what they’re talking about, but that’s the deal with writers they just take things that they’ve heard and don’t do any research. LED light bulbs are three times more efficient than fluorescent light bulbs
Elizabeth Chrissian says
frankly I became very confused
M. Pockets says
You must be a writer.
Rayann Anema says
Will my sad light for depression help. It has 10000 lumens and white light.
Ken Nguyen-Scott says
Yes, any white light (which by definition has all the colors of the spectrum) if it’s bright enough will help plants grow.
Hugh Reifsteck says
I read your post very helpful to me because i am a Engineer.
Steven says
That’s great to hear, thanks!
Anonymous says
An enginee
Ahmed Badawy says
an engeneer 😉
Ahmed Badawy says
an engineer
Albert florez says
I’m a jackass Mexican imagrint. Me noooo Nintendo anytink day u say goin hohn.
Eric Ryan says
I have a come across a lot of stage lighting.While the 1000 watt fixtures are stick halogen bulbs we all are used to.seeing,the par 64 cans are a headlight bulb halogen that can be 300-500-1000 watt depending on size and then my fav,these projectors,250.osram bulb with fan on back of box.it has two wheels inside the projector box with glass ripple effect on one wheel and colored panels on other wheel.two motors,a ballast that must be in the projector for the bulb.A nickel size magnifying glass is the discharge direction for this little bulb inside a reflector that is silver dollar size with a bulb that is not much bigger than average flashlight bulb.24V and 250 watt.R these good or addition to my400hps?
Steven says
I’m assuming it’s white light, in which case it will definitely help. The main issue is efficiency. How much output do you get for that 250w? And how much heat does it generate. The reason people use HPS or MH is because you get a lot of output for the wattage and the heat is not as bad as some other forms of lighting (like incandescent).
Fred says
Would using red LED’s be adequate along with the 5000K LED’s for growing plants that flower? I seen red LED’s at a local hardware store and was contemplating on buying them but was unsure as to whether or not they would be useful. I have a greenhouse
10 X 12 and plan to use the daylight LED’s and from what I can understand the Red LED’s, along with the daylight LED’s would nullify the need for the “proper” grow lamps which are quite expensive.
Thanks!!
Steven says
They would help, but would not be quite the same as a grow light with a proper spectrum. Plants want both red and deep red light, and in a specific ratio, for ideal results.
Anonymous says
Qa
Fred says
Okay thanks!!
jonski says
hi i have a potted christmas tree… its under a 6500 cool white goose neck floor lamp… not 3 but one lamp… i plan on running this 4 hours in the night… is that enogh? or do i just leave it
Marian says
Can horticultural LED lights be used in a regular light fixture?
Steven says
Some of them can. It will always say so in the description. If there’s a photo, you can also see if it has the same screw-in ending as a regular light bulb.
Stephen says
The author has not done his research Google grow off-the-shelf LED light bulbs you’ll find hundreds if not thousands of people using them to grow plants. Yes regular LED light bulbs can be used
Cranky says
The author never said otherwise., He stated that daylight and cool white LEDs will work perfectly well for vegetative growth, but will not be sufficiently powerful for flowing – and in that he is correct. However, the amount of lumens output is important factor too.
Elaine says
I recently bought a 100 watt led bulb that is white light/daylight and was labeled at 5000kelvin, I have it hanging from a pendant lamp cord about 3-5 feet above my plants in an east facing window, it’s too make sure they get enough light even on overcast days since they only really get a few hours of morning sunlight and it’ll be autumn soon so less sunlight hours.I have tropical foliage and succulents, is this enough lighting? I’ve been researching lighting for plants but I keep getting conflicting information.
Steven says
That’s impossible to know without much more info. Just watch the plants. If they’re not getting enough light, they’ll show you.
Elaine says
What other information is needed for you or someone else who knows about lighting to let me know if this type of lighting is good for my plants or not? The “ wait and see” approach isn’t realistic for me.
Steven says
Unfortunately, that’s really the only option. We can’t possibly know how much light your plants need, how much they are already getting and how much that bulb provides. If you want to be safe, buy more bulbs, but I would just wait until your plants tell you they need more light.
Ale says
Hi there,
I’m looking a LED light for growing veg, a lot of articles recommend above 5000k others say that 4500k is the best choice. I wanna know if any of you guys have a recommendation for me. I read too that between 2000 and 3000 lm but I don’t know if 1500 lm are ok.
Thanks :).
Steven says
If it’s just veg, go with 4000K – 6000K. They will all work fine. I have no idea what you’re asking with the lumen. Ok for what?
Veeral says
I am now even more confused! so what you are saying is that if i go to a regular electrical store, pick up some run of the mill white (6500K)LED tubes they should work just fine? I am trying to bring my succulents indoors for the winters and grow lights are expensive in our country.
Do you suppose regular LED tubes, not labelled as grow lights should work fine for these?
Thank you
Steven says
yes
Michael T. says
Last year took my plants to a cool house with not enough light. They were losing the bottom lea-es. I put them in my bathroom at night with strong LED lighting and they got better It was warmer in the bathroom but the brightness appeared to help.
My same plants are back at my apartment where they always are but not in the summers. As is the case each year, they lose a lea or two or three weekly this season. I take them at night and place them close to my LED lights at night, two to three hours. This appears to work well. The thing is, where I position my regular lighting is quite naturally not where my windows are. Most people do the same, because who needs light by a window during the day? So it’s unclear that perhaps pants just like being away =rom windows at night which generally incur slight cold air coming through and are generally at colder spots in a home. What country do you reside in?
TM says
Succulents produce stunning flowers and often need the (winter’s coming) swing towards more red end light, as well as other environmental changes to go into winter stage. 6500 is heavy on the blue side and very light on red end. 3500-4000k is pretty middle of the road. I use combinations of 15w 5000k and 2700k bulbs together so I have the spectral ends covered, the middle is heavy for both warm and cool lights. Together they work very well.
Steven says
Thanks for the added info! That’s a great light combo for most plants.
Kia says
Hello
thanks for your great helps. I use four LED bubble lamps(not full spectrum),two lamp 1800Lm 6500K and two 1700Lm 3000K(normal LED for home use and etc) but my plants are too short with dark green leaves.
What’s wrong? Please help me.thanks
Steven says
Things like this are impossible to diagnose from a distance and with such limited info. You didn’t even mention what type of plants they are. Probably those lights are too weak.
Kia says
Cannabis plants.my grow box is 30 cm width 50 cm length and 100 cm height.
Anonymous says
I am using a 1000w (185 draw from the wall) Bestva LED light with two clones in flowering stage. Can I use a cfl or two and have ,them positioned at the bottom for supplemental lighting? I read plants do better with different colors implemented with your burple (blue red) lights….? I have a 2x2x4 tent.
Steven says
Yes, you can do that.
Anonymous says
Thanks Steven for the response. I’ll try it out and see if I see any change from week to week.
Teresa burnett says
I was given four LED four foot lights to start growing some microgreens in my kitchen. They do not have any words on the boxes that they are grow lights. They only say 30 watts…3000 lumens…Color accuracy 82 and 4000K. Do they fit the profile of a grow light? They are nice and bright. What do you think?
Steven says
Any light can grow plants and these have a good spectrum (4000K). They’re not very strong, but could be enough for microgreens. Try them and if you need more light, you can just add a few more.
James Pennock says
The article wasn’t perfect in its technical accuracy. But compared to other informational resources on the internet this was the most inclusive. It was presented at a level DIY indoor home growers could comprehend. It’s a great starting point for those new growers, despite the occassional negative reply. Thank you for this information.
Bob says
We have recently been buying hydroponic lettuce when my octo-g brain lit up. I saved the core growth of the last 4 plants and potted them in light potting soil in 4 small pots. Knowing they would have to produce a soil root structure I used 10-52-10 initially and in another week I will change to 20-20-20 for vegetative growth. They have now doubled in size in a few weeks. I have the pott sitting on the countertop beneath a day light 4′ fluorescent attached beneath the cupboard plus 2 13.8 W 5000 K leds hanging in front. I also placed a shaving mirror in front and laid some salvaged HD disks underneath.
Steven says
Nice going!
Bob says
With the success of regrowing my hydroponic lettuce I’m considering a larger setup for lettuce, arugula, and basil. In fact I now have those hydroponic plants on the floor in a row with 3 13.8 W 5000 K 1575 L hanging above. What would you suggest a good distance between bulbs and plants? I have 4 more of these bulbs. If I can find some more I assume by rereading your site that 6000 or 7000 K could be even better for greens if I can get them.
Steven says
This post covers hanging heights for various lights: http://growlightinfo.com/grow-lights-distance-from-plants/
Bob says
With hydroponic greens coming on the scene one can start indoor gardening without planting seed.
See picture: http://mypics.findmoore.net/images/phylades/growing.jpg
Nevertheless I will do some planting. The big plant in the foreground just came from the store like the 4 rear ones which were picked to the central core and potted. These were fed 10-52-10 initially to rehabilitate the hydroponic roots to the soil. This was done on the kitchen countertop under a fluorescent tube app. 3-4 weeks ago until a week ago when I set up this mock-up of a 3 level 18 bulb 1475 Lumen 5000 Kelvin LED that I have in mind. That lush plant in the foreground was one of 2 totally wilted given to me by the store clerk who was sold on starting his plants at the sight of a picture. The yet unknown factor is how long these rehabilitated potted plants can be harvested. Bolting should be much slower indoors.
Andre Coop says
I need light and heat because I’m starting seeds in my basement.
Will a standard 60W GE “reveal” nightstand bulb work?
John says
If you got some mylar or aluminum foil and wrapped it in the inside of a cardboard box the bulb might provide heat, but they will be very stunted plants if you can’t get a better light plus some wind to blow on them. Even a computer power supply with a case fan or two could be blowing on them and you can scrap those from just about anywhere. If you took them outside during the day and brought them in at night that would be even better. Here’s something that might suit you- https://amzn.to/2SFC4E6
Ellie says
Found this super helpful! Thanks very much
joali bernal says
i just had my first indoor plant which is a rubber tree plant as they call it, what type of alternative plant lighting is recommended, should it be LED or fluorescent light, please help.
Steven says
LED is better overall.
Anonymous says
I have used a 25 watt cfl or fluoresce light bulb for a small 6 sq foot rectangular garden will it work?
I___o___I
The lines are each. Sq foot and the o is the 25 watt cfl lighi.
I have flowers and veggies in ma garden and a grafted lemon plant.
Will it work for my garden?
Steven says
I doubt that will be enough. Follow the advice in this article: http://growlightinfo.com/how-many-cfls-per-plant/
scrungus says
that graph is hilariously bad with the comparison of bulbs v efficiency, length of time and used by plants. the plants column is like making my eyes see green in more holes than there are bc the shades are barely diff lmao
Steven says
You may be somewhat color blind. I’m not trying to be mean (I realize it might sound that way). The difference is quite easy to see for me, so I just thought that may be the issue. It could also be a poorly calibrated monitor, though.
Angel says
I have 2 100w led lights over one plant in a 2×2 box
Is that enough light for it to start to flowing/budding?
Steven says
If they actually use 100 watts, then probably. But if they are labeled as 100 watts, but only use 10 or whatever, then no.
Russel Black says
LEDs are definitely the best choice for indoor growing right now. Good yields, less money spent on electrical bills and no heat generated in comparison to CMH lights. And also better than fluorescent lights. Ive been running with il8x from iluminar which is fully dimmable and adjustable and its working wonders on my crops, Couldnt be happier