As you look for the right grow lights for your needs and space, keep in mind to always look for the greenest lighting options possible. Even slight efficiencies like placing your lights near sunny windows or finding lights with timers can really add up over the years. You can feel good knowing you’re practicing green habits like gardening while reducing your carbon footprint overall.
Think of your grow lights as a long-term investment. You’ll be able to use them every single season to grow great-tasting herbs or any other plant. They're particularly beneficial in for growing seedlings before it's warm enough to plant outdoors. Starting your own plants from seeds can also help you save money compared to buying nursery starts. Perhaps best of all is the life and brightness they bring to those darker months of the year. Here are some of the best grow lights you’ll want to look at as you get your own indoor setup started.
Buyer’s GuideBefore buying an LED grow light, read our buyer’s guide below to learn about important factors that’ll help you make an informed purchasing decision.
CoverageGrow lights typically give you measurements for how much vegetative and flowering coverage they offer. Be sure to choose a light that matches the amount of light and type of coverage you need for your growing area such as an indoor garden or a plant wall.
WattageA grow light’s wattage determines how much light it produces. Different plants require different amounts of light, so don’t just choose the light with the highest wattage to ensure optimal plant growth. Instead, match the wattage to the plants you’re growing. For example, if you’re growing tomatoes, choose a grower that offers about 32 watts of light per square foot.
AdjustabilitySeveral features of your LED grow light should be adjustable.
Color: Plants need a different color light for every step of their growing cycle. The best grow lights offer red lights, blue lights, and white light color options.
Brightness: In addition to color adjustability, LED growers usually have knobs for adjusting the brightness of their light bulbs to ensure optimal light intensity.
Proximity: You can also adjust how close the lights are to your plants by lengthening or shortening the rope or chain they’re hanging from.
What to Look For in a Grow Light
SizeWhen deciding which size grow light you need, think about how many plants you need to cover and where you intend to put them. If you plan to move your light from place to place, opt for something lighter and portable. If you know it’s going to stay put, that might not be as much of a factor. Wherever you plan to put it, make sure there’s room for it to operate safely and not up against furniture, drapes, or other items.
TypeThere are various types of grow lights to consider, from panels to products that hang overhead or screw into standard light fixtures. The type of plants you have, the amount of existing natural light, and where your plants are located help you narrow down your choices. Typically, hanging lights are larger, while desktop lights are smaller and easy to move around. If you want a complete system, consider a full garden kit that includes the planter with a built-in light.
Location“Hanging your lights too low can burn your plants, but hanging them too high can leave them stretching for light, and weak,” says Kansas City-based Melissa Lallo Johnson, host of Art of Gardening, a vlog and podcast that features influential gardeners from around the world. The standard placement recommendation for incandescent grow lights is at least 24 inches from plants. Since fluorescent and LED lights have lower heat outputs, they can be placed 12 to 18 inches away from plants.
Different plants require different intensities of light, however. If you grow seedlings, Johnson recommends positioning them within 2 to 3 inches of a fluorescent light source, or as close to the light as possible without touching it. Hanging or positioning lights directly over plants is the best arrangement, because that mimics sunlight and ensures that the entire plant receives adequate light.
WattageWattage is a useful tool to determine the correct fixture for your plants. Generally, you need 32 watts per square foot, so most indoor plants (especially herbs) do just fine with a lower-watt light. The more important metric is PPFD, or photosynthetic photon flux density, which measures the specific light emission a lamp gives off.4 Not all products list this, however.
Bulb TypeLED lights are one of the most popular, as well as the most efficient options. They also offer ideal light spectrum ranges. LEDs emit less heat than incandescent bulbs and can last up to 30 times longer.
“LED lights are my preferred go-to for lights, because they’re energy-efficient and generate little to no heat,” Johnson says.
Fluorescent lights are more energy efficient than incandescent bulbs, but they tend to be pricier.
Incandescent bulbs are the least-expensive option, but they’re also the least energy efficient. They also have fairly high heat outputs, which is not the most ideal growing condition.
Growing SeasonThe beauty of indoor grow lights is they allow herbs, seeds, houseplants, and flowers to flourish year-round. However, they need the right amount of sunlight and darkness to thrive. Johnson says that for germination and seedlings, you can run lights 16 to 18 hours per day until they are a few inches tall. "As they mature," she adds, "you can slowly reduce to get them on a similar light pattern for spring before you transplant them.”
After some experimenting, you should be able to peg the optimal duration for your specific plant variety. A grow light with a built-in timer makes it easier to control proper light levels, especially if you’re away from home. Johnson suggests that you try to get the light schedule as close as possible to the current sun pattern, so your plants are less shocked when transplanted outdoors.”
How far should grow lights be from plants?Though it depends on the wattage and light wavelengths, you should position grow lights at least 2 feet away from your indoor plants to avoid overheating. LEDs and fluorescent lights typically have lower heat outputs, so they can be placed a little closer.
How long should grow lights be on?To effectively mimic the sun's natural light, a grow light should be on 8-16 hours a day, depending on where you live, what time of year it is, and the type of plant. Generally, if your plants receive some natural light, they don't need as much artificial light. A plant that doesn't get any natural light may need the full 16 hours.
Do you have to use LED lights?LEDs are most often recommended for grow lights, though some fluorescent and incandescent bulbs can work. The most important thing is that regardless of type, the bulbs should offer full-spectrum illumination and produce waves of red and blue light, which is often necessary for plants to thrive indoors.