Can You Use Regular Light Bulbs As Grow Lights?
Last updated September 8, 2019 By Steven 50 Comments
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.
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 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.
A comparison of incandescent, fluorescent and LED bulbs when used as grow lights for plants. Incandescent bulbs use the most power, last the shortest amount of time and provide the least amount of usable output for plants.
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.
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 vegging and for plants that do not bloom, use bulbs labeled as ‘daylight’ or ‘cool white’. The color temperature on these bulbs will be between 6000 K and 7000 K.
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’ like these. In terms of color temperature, they will be between 2000 K and 3500 K.
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’).
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 led lights to grow plants?
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.
On the other hand, if they 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.
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.
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 quality one like this one doesn’t have to cost a lot.
Regular light bulbs can be used as grow lights, but some are better for horticultural use than others and LEDs are a special case. You need to…
Growing Plants With A Desk Lamp – An Easy Guide For Plant Lovers
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Plants are a great addition to any room. They look nice, they make the air fresher, and they can help to improve your mood too.
That last point is such a trope that in classic video games such as Theme Hospital, adding a plant to one of the offices would boost the happiness of anyone in that office!
So can you grow plants with a desk lamp ? Yes! The challenge, though, is that plants need specific light to thrive. This is a guide that will give you all the necessary information.
For those that are in a hurry and looking to buy a good growing lamp we suggest to check out our top pick below:
The best part of this hydroponic garden lamp is simplicity – compact and easy to use. It produces full-spectrum light that mimics daylight. You can easily set the timer for the lights and will alert you if the water levels are low. If you watch the water levels then your herbs and plants will grow as if you are an expert in gardening.
Growing Plants Using Artificial Light
It is possible to grow houseplants indoors. However, you will need a special kind of light to do so.
You can make a plant grow by using a desk grow lamp but a standard incandescent bulb or an energy saving light bulb probably won’t do the job.
Sunlight contains the right balance of light wavelengths to make plants bloom and artificial light usually doesn’t have the same spectrum of light waves in it.
For a plant to thrive, it needs:
Blue light for foliage growth Red light to make it flower
Other light will get reflected. Indeed, it is the green wavelength being reflected that makes leaves appear to be green to our eyes.
We are going to answer some of the more frequently asked questions about grow lights:
- Can a regular light bulb help plants grow?
Yes, you can grow a plant with them, but it’s not the best idea. Their spectrum is concentrated on the warm (orange) light, so it is not ideal for foliage growth, which requires more cool (blue-ish) light.
- Can you use a grow light bulb in a regular lamp?
Yes. If the regular lamp has the correct socket type and wattage capacity, a grow light bulb should fit into a regular lamp without any problems.
- Is natural light or artificial light better for plants?
Nature light is always better for plants because it has a more complete spectrum than any artificial light.
Ideally, an indoor plant should still have some exposure to natural light. Artificial light should be treated as a supplement rather than an alternative. If you are growing plants indoors, it is better to have them next to the window during the day.
The Different Types of Grow Light Bulbs
Today many different kinds of a light bulbs exist so let’s take a look at them in turn:
If you want to grow houseplants then fluorescent bulbs are a good option.
They are quite affordable, and they tend not to get too hot when they are in use, either, so they can be placed fairly close to the plant. These bulbs have a long life of about 20,000 hrs and, as such, has been the popular growth light source for a long time.
Choose the tube or a bulb carefully, though. Standard tubes produce light that skews towards the blue wavelength, and that’s not what you really want.
Ideally, you should look for a full-spectrum fluorescent tube that will include cool and warm light colors.
If you’re not sure what tube to choose, pick one that is marketed as ‘cool white’ because white light will include the full spectrum. Keep the tube about a foot away from your plant’s foliage for best results.
Regular incandescent bulbs get quite warm, and they aren’t all that energy efficient. They give off more red wavelength light than white. They only last about 1,000 hrs.
A regular light bulb can produce the necessary spectrum for plant growth. It needs to be carefully chosen to have the best effect.
It is getting hard to find these bulbs in some parts of the world because they are being phased out in favor of more energy efficient bulbs.
They burn a lot of energy, and the filaments blow more quickly than most other types. Look for something more energy efficient if you can.
LEDs are a good choice for a grow light bulb because you can get them in almost any color.
Good quality LED has a complete spectrum, and doesn’t produce much heat and waste energy. It has a super long life of 50,000 hours; therefore, it is ideal for growing plants. Although the LED cost can be much higher than other light sources, so the initial investment is higher.
If you don’t like the color of the light that is produced by those, then you could look for more neutral LED lights as long as they have the right spectrum included.
The good things about LED lights are that they do not tend to get hot and they are incredibly long-lasting and energy efficient.
They can be more expensive to buy upfront than other varieties, but they should last for years and they generally provide the best light for growing plants indoors.
Similar to incandescent light, halogen light has a sunlight-like spectrum and is more energy-efficient than incandescent light.
It lasts up to 4,000 hours, but still generates considerable heat and concentrates more on the warm light spectrum. It is not ideal for all growth stages.
Specialized horticultural lights are the most advanced light source for growing plants.
They usually come with a particular light spectrum, like a red light for flower growth or blue light to grow leaves. They are professional products for large farms that aim for high yields and performance but can be expensive.
If you are only looking for small scale indoor gardening as a hobby, it is unnecessary to use professional horticultural light.
How much light do plants need to grow indoors?
The quantity of light is measured by the unit ‘lux’.
One lux is defined as the light from one candle at one-meter distance spread over 1 square meter.
Plants have different light requirements. Sun-loving plants usually need at least 25,000 to 50,000 lux to do well, while shade-loving plants need only 2,500–10,000lux.
Direct sunlight is approximately 100,000 lux, and indirect sunlight gives approximately 20,000lux. Overcast sky gives approximately 2,000lux.
Comparing to natural light, the home light source produces much less light(up to 5,000lux). Therefore, many indoor plants still need to be placed near the window to have their daylight and augmented with artificial light for maximum growth.
Below is a table of how much light is required for each plant type and how they can be grown at home with artificial light:
Hours of light
Different plants also need different hours of light exposure.
Plants can be categorized into a few different types:
Long-day plants require 14 to 18 hours of light; if they don’t receive enough, they get pale and leggy.
Short-day plants, such as chrysanthemums, kalanchoe, azaleas, and begonias, need less than 12 hours of light per day.
Day-neutral plants, including foliage plants, geraniums, coleus, and African violets can usually thrive with 8 to 12 hours of light all year-round.
Usually, the plant’s foliage will tell you whether they are receiving enough light.
A mid-green color to the foliage indicates the plants are receiving the correct amount of light. In contrast, a bleached appearance, yellow-green foliage, or stunted growth means there is too much light. When the foliage becomes a dark green, it means too little light is received.
Plants need light to grow, but they also need some darkness.
While it’s dark, the plants will respirate, and this is just as important a part of the growing process. If they don’t get rest, then they will not thrive properly.
If you want to grow plants using a desk lamp then it is important that you pay attention to this lighting issue.
You cannot simply buy a plant and change your bulbs, then forget about it.
Think about light as being another form of food, because that’s exactly what it is to a plant. We eat, they photosynthesize – and photosynthesis uses light.
It’s a good idea to invest in a timer for your lamp so that it will be turned on and off to the right schedule.
This may mean that you have the light on even when you’re not using the room, but don’t worry too much about that. Desk lamps, especially LED ones, do not use very much energy at all.
If you really want the ultimate in convenience, there are ‘smart garden’ tools that you can get, including pots with a lamp above them and a reservoir with a mister.
These will keep the plants watered for you at the right rate, as long as you remember to refill the reservoir.
How reliable this is will depend on how humid/warm your rooms are and the plant that you choose. There’s still no substitute for human knowledge when it comes to tending your plants!
Light Spectrum And Color Temperature
Plants primarily use blue and red light for growth, but research has shown some species perform best under the full spectrum that is similar to sunlight.
While natural light varies in color temperature throughout the day, artificial light has a static color temperature. If you want to promote a particular growth stage, it is recommended to choose a full spectrum light with a specific color temperature.
The general rule is to choose a full spectrum grow light with a color temperature in the blue range (5,000 – 7,000K) that will promote vegetative growth.
To promote fruiting and flowering, choose a color temperature in the red spectrum (3,500 – 4,500K).
The correct position of the light source
Keep the right distance!
To grow plants at home, it is better to use lamps with adjustable arms so that you can move the light source away from the plants as they grow taller.
It is recommended to keep the light source at least 3″ away from the top of the plant if you are using an LED or fluorescent lamp and 6″ or more for incandescent or halogen lights. Keeping a light too close runs the risk that the plant is ‘burnt’ by the heat from the light source.
An excellent way to test: Sticking your hand above the plant under the light, you should not feel warmer than under the sunlight.
Another important aspect is to keep the right light intensity.
The light source also needs to be at the right height so that the right amount of lux level is achieved on the foliage. There are a few lux meter apps available for mobile phones.
More serious growers can invest in a lux meter to get the accurate lux level reading above the plant. Most importantly, the light intensity needs to be consistent. Also, make sure to purchase a broad beam light to cover the whole planting area.
What Plants Will Grow Indoors?
Most plants can grow indoors if you get the right bulb for your lamp.
Grow lights can help to start seeds so that you can plant them outside once they are stronger seedlings.
You can grow herbs indoors so that you can enjoy a fresh harvest even in the winter, and you can get thriving, vibrant houseplants with the right spectrum of light too.
Choose Low Maintenance House Plants
If you are someone who doesn’t know a lot about gardening, or someone who is rarely at home, then you should choose a plant that is fairly low maintenance.
Aloe, Spider Plants, Snake Plant, and Lavender all fit the bill in terms of not needing a lot of specialist care.
Spider plants, however, grow very quickly and you may end up needing to re-pot them, or ending up with offshoots that you can give away to your friends and family.
Once you get the hang of those ‘easy’ plants you can start looking at others that need a bit more care.
Remember that even supposedly ‘hard to kill’ plants such as cactus can still wither if they aren’t looked after properly.
Make sure that they get the right amount of light and the right amount of water.
Many people over-water cacti or forget that it is possible for a succulent to become damaged from too much sun exposure.
So, don’t put your cactus on a windowsill, and if you’re exposing it to a desk lamp instead, make sure that the light isn’t too harsh or too close to it so that the leaves don’t get damaged.
Here you will find 3 products that we recommend for easier plant grow. They are very convenient for first time plant growers and for experienced ones also.
1. All in one indoor garden system by Mindful Design
This is a great lamp for plants!
The product is a simple and compact system complete with white LED light and water system.
It is ideal for someone who wants a nice looking small patch of indoor green with low maintenance.
The product produces 4000K full-spectrum white light similar to natural daylight. It can substitute the lack of daylight for indoor plants.
It is an easy to maintain system with an automatic timer to allow you to set up when the light will be on and off. It also alerts you if the water is too low. Once set up, all you need to do is keep an eye on the water levels.
The white light and the product’s compact design fits great into any home environment. The product would look particularly great in the living room or kitchen.
It is a relatively small plant pot. The product’s main compartment has limited growing space for plants, so only small plants, like herbs and certain flowers, can fit into the system.
Nonetheless, it is still a great starting kit for everyone who wants to start growing plants indoors.
2. Grow Light for Indoor Plant by Elaine
A dedicated plant light that produces full-spectrum white light similar to daylight, to supplement lack of daylight exposure for indoor plants.
It is highly customizable and adjustable, suitable for gardening fans constrained by indoor space.
This product produces sun-like full-spectrum white light which is similar to and can be a substitute for daylight.
It has added red light to increase yield and promote flowering. With various dimming options that can adapt to different plants’ need for daylight.
Also comes with 3 timing settings. Once you choose repeat at first time, it will turn on/off automatically and you don’t need to do anything. Amazing!
The product comes with a 360 degree goose-neck type to cover numerous plants of various sizes. The white light it produces is comfortable to look at the in-home environment.
This lamp can also double as a desk light which can be quite useful.
On the other hand, this lamp doesn’t allow selective blue/red light output to optimize particular growth stages, e.g, using more red like for germination and root growth, and more blue for leave growth.
Higher energy consumption than blue/red light only products are also some negative aspects of this product.
3. Red and blue plant light from Amsuns
This lamp produces the critical red and blue light spectrum that promotes plants’ growth.
Ideally used as supplemental light for outdoor plants that need extra help at a particular stage, or indoor plants exposed to daylight but needed some extra ‘vitamins’.
It is ideal for someone keen on getting good gardening results and willing to make the extra effort.
The product has flexible and adjustable blue/red light working mode setting to suit different stages of plants’ growth, e.g using more red light at plants’ early stage to help germination and root growth; using more blue light at the growing stage for stronger leaves and stems.
Also has multiple dimmable levels and timer settings to suit a specific plant’s needs which is always useful.
Adjustable arms can be adapted to suit a wide variety of plants and coverage areas.
The main disadvantage is the ability that it concentrates on the blue and red spectrum only. It can’t substitute natural light. The plants still need to be exposed to full-spectrum natural light to grow healthy.
If you are looking on the aesthetic side then maybe this lamp isn’t for you. Because blue and red light may not fit well in a home environment. It is a dedicated plant light not meant to look pretty.
Ever wondered can you grow plants with a desk lamp ? This simple but informative guide will teach you how to do it the right way.