Home
Fact-checked

At HomeQuestionsAnswered, we're committed to delivering accurate, trustworthy information. Our expert-authored content is rigorously fact-checked and sourced from credible authorities. Discover how we uphold the highest standards in providing you with reliable knowledge.

Learn more...

How Do I Choose the Best Hydroponic Grow Lights?

Jeremy Laukkonen
Jeremy Laukkonen

There are a number of factors you may want to consider when looking for the best hydroponic grow lights, such as your budget, the types of plants you want to grow, and the area you need to light. The most important factor to remember is that hydroponic grow lights need to put out a certain spectrum of light, which can be provided by a few different types of bulbs. If you plan on growing mainly leafy vegetables such as lettuce then fluorescent or metal halide lamps will typically do a good job. High pressure sodium (HPS) lights are another option that can be especially well suited if you want to grow fruiting plants such as tomatoes. You will typically want to have about 40 watts for each square foot in your hydroponic growing system, though that can differ with various types of plants.

Hydroponic grow lights are the primary light source for plants that are grown indoors in liquid based mediums. Since the plants are indoors, it is necessary to provide them with a certain spectrum of light that can support necessary biological functions. Normal incandescent light bulbs typically do not provide this spectrum, but a number of other options do. The type of light provided by different types of light bulbs is sometimes referred to by color temperature, and the desired number for most grow lights is about 5,600° Kelvin (K). Any bulb that is in that general range can be a good hydroponic grow light.

Woman with a flower
Woman with a flower

The least expensive light bulbs that can fit into the correct color temperature range are typically fluorescent. If budget is an important concern to you, then you may want to consider fluorescent hydroponic grow lights. It is important to remember that not all fluorescent bulbs output light in the 5,600 K range, so you need to check the ratings on a bulb before purchasing it. Both metal halide lamps and high pressure sodium lights can also be good grow lights, and you may want to consider an HPS bulb if you grow tomatoes or other fruiting or flowering plants.

Another factor that can help you select the best hydroponic grow lights is wattage. The necessary wattage can vary from one type of plant to another, and fruiting plants typically need more light than leafy vegetables. If you grow tomatoes then you will want a grow light that puts out about 40 watts for each square foot of growing space, so in order to choose the best lamp you will need to determine how large your growing area is. You may also want to consider the durability of a light since hydroponic systems can result in high humidity environments. A unit with an electronic ballast is necessary if you want to use an automatic light timer, but you will also need to ensure that the additional electronics do not break down in the environment created by your hydroponic system.

Discussion Comments

pastanaga

@bythewell - The same kinds of lights used for hydroponics are also used for aquariums and they don't tend to be that dangerous, especially now that we've got the option of using LEDs, which don't overheat the way halide lamps would.

Most people reading this aren't going to be setting up a commercial operation. They'll just be looking for a little extra light so they can grow a herb garden indoors or something like that.

bythewell

@browncoat - Hydroponic light systems tend to be fairly powerful and I really don't think anyone should cut corners when setting one up, particularly if they are beginner or planning on creating an extensive system.

You will want to have warranted parts so that you can get them replaced if you need to. And you will want bulbs that haven't seen much, or any, use, since they only last so many hours. If you get them secondhand there's no real way of knowing how much time they have left and they can be expensive to replace.

You're also going to need to make sure that it's safe. Hydroponics involves relatively large amounts of electricity and water in the same area and the last thing anyone wants is for those to mix in the wrong way. At best you'll ruin your system, but at worse you might kill someone.

This isn't the kind of thing that people should try to jury-rig. It's too dangerous.

browncoat

You might be able to find a good setup secondhand if you keep an eye on auction websites and noticeboards. This is the kind of hobby that a lot of people will take up without doing enough research into what they need to continue it, which means they'll be happy to unload their equipment.

I've also noticed that you can get relatively cheap lighting from overseas if you find the right website, but be careful that you'll be getting lights that won't need an electrical adapter.

Post your comments
Login:
Forgot password?
Register:
    • Woman with a flower
      Woman with a flower