What Are The Best Lights For Microgreens?
The title of this article asks a very broad question that will interest a wide range of microgreen growers.
A question that requires some context to be answered.
Such as, how many trays of microgreens do you grow at one time? Do you sell microgreens or only grow what your family can use?
What types of microgreens do you grow, quick-growing varieties, or those that take 3 weeks to mature?
Where do you grow your microgreens, in a spare room, or in a living area where you and others can see them? And lastly, maybe the most crucial question, what is your budget?
Focused On The Home Microgreen Grower
If you're growing microgreens to sell, don't leave yet. Please, if nothing else, leave a comment on what type of lights you use to grow microgreens. The information will help everyone make a more educated decision.
Categories and Types Of Lights For Growing Microgreens
There are four categories and three general types of lights that will grow microgreens. We're leaving out natural sunlight, but don't forget, microgreens placed in a southerly facing window (in the northern hemisphere) will grow just fine.
The light categories are incandescent, fluorescent, LED, and what we call metal vapor lights. The types of lights are regular (non-labeled), full-spectrum, and grow lights. Grow lights can be further broken down to red bloom and sun white.
We're trying to keep this article simple and not get into the complexities of light. We will publish a comprehensive article in Garden Permaculture soon.
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For all intents and purposes, these types of lights are extinct. The world is going LED so don't expect incandescent light bulbs to be available for purchase very much longer. They use too much energy, put off a lot of heat, burn out quickly, and their spectral wavelength isn't that great for plants anyway.
Metal Vapor Lights
These lights work by ionizing a mixture of gases in an electric arc. The different metals i.e., mercury and sodium, create the color intensity. Commercial growers use metal vapor lights because they are very powerful, and the spectral wavelengths are great for plant growth.
Metal vapor lights are expensive to buy and to operate. They also burn quite hot. For these reasons, vapor lights are not recommended for the home microgreen grower.
Fluorescent lights are commonly used by gardeners and microgreen growers. Although, most are now switching over to LED lights. Still, some growers swear that fluorescent lighting is the preferred light.
Though more economical than incandescent and metal vapor lights, there are drawbacks to using fluorescent bulbs. The bulbs are made of thin glass and break easily. Also, they contain heavy metals and need to be disposed of properly.
The two most significant drawbacks, though, are that they lose their brightness and the ballast that powers the light can cause interference with electrical devices.
LED Replacement Bulbs For Fluorescent Lights
If you have an older fluorescent shop light laying around, you can add LED bulbs to it following a few modifications. Active Grow sells horticultural replacement bulbs and presents a video to show you how to remove the ballast and easily rewire the light fixture.
We Recommend LED Lights
We like LED lights for several reasons. LED lights, either bulbs or fixtures are:
- Lightweight making them easy to mount
- They come plug and play - no wiring
- Produce little to no extra heat
- Use way less energy
- You can drop them, and they don't usually break - no glass
- Less heavy metals
- Cause no electrical interference
- Last 40,000 to 50,000 hours with no change in spectral wavelengths
- Prices are dropping
LED lights are the future. Go to any home improvement store, and you'll notice an increase in LED bulbs and fixtures and way less fluorescent and incandescent lights.
In the past three years of us growing microgreens, we have seen a considerable change in the quality and decrease in the price of LED lights. It's only going to get better, so we will try to update our recommended lights as much as possible.
Which LED Lights Do We Recommend For Microgreens
If you're growing a tray of microgreens here and there, go with price. Even choose an LED shop light from one of the box stores.
The essential requirements are as much wattage as possible and a light temperature of at least 4,000k but preferably higher, such as 5,000 to 6,500k. The light temperature, or K for Kevin, is the light temperature or color. The higher the number, the closer it is to sunlight or natural light.
Below is a rack of microgreens where we're experimenting with lights. This is our early experiments.
The lights, from top to bottom, are a single LED 4,000K light, 2 LED lights of 3,000K, and a single LED of 6,500K.
First, notice that the higher the K-value, the brighter or more natural the light color. Also, notice that two lights of the same temperature (middle lights) don't change the color, it only intensifies the power of the light.
The biggest take away should be that ALL of the microgreens are growing great. Still, it's our experience that the higher the K-value, the better the plants grow. Remember also that the wattage, or power, is important too.
We aren't recommending any of these lights, because now there are better ones.
More Current LED Lights For Microgreens
The images below show the lights we have bought for our newest microgreen rack. The first lights are economical, and we use those for microgreens we eat or show at our presentations. These are manufactured by Barrina.
The second lights are full-spectrum, sun white, grow lights, and are a bit more expensive. We use these lights for a new venture in selling mature microgreens to restaurants and stores. These lights are manufactured by Active Grow.
The top light in the second photo is a Barrina light to compare it to the lower two lights, which are Active Grow.
What's The Difference Between Barrina & Active Grow
Well, besides the cost, the Active Grow lights are built better and have data that supports their claims to being actual grow lights. It takes two Barrina lights to cover the 2- by 4-foot shelf area, while one Active Grow light does provide the coverage.
We wish we could test the Barrina lights as to their output, output area, and spectral wavelengths. But we'd need this PAR meter, and that's not in the budget. But if someone wanted to purchase it for us, we'd go to town testing lights! More on why this meter is important in a soon to be published Garden Permaculture article.
Our Recommended Inexpensive LED Light For Microgreens
Although these lights don't look like much, they have a high K value and grow microgreens quickly and with good color.
We purchased these lights and mounted two per shelf to make sure they have the needed light intensity over the eight square feet. Below are several options, we bought the pack of 6 of sun white LED's over the red bloom color.
We think microgreens grow better under the full spectrum sun white than the red bloom.
You can see that these lights are very economical and to our surprise, the lights come with a wide range of hardware to connect, daisy chain, and hang the lights. We also like that the lights are plug and play (so easy), and each cord has an off and on switch.
We will be buying more of these lights for future expansions.
We decided to try these Active Grow because of the intensity coverage these lights possess. We use one Active Grow 4-ft 40-watt LED sun white full spectrum grow light per shelf. The intensity coverage map is shown below and is compared to an equal fluorescent light.
Maybe the chart confuses the matter, but the point is that light intensity (middle row is the light we bought) is substantial over the whole area.
We find little growth variance over the 8-square feet, and that's what we want.
The active grow lights also come with many ways to connect, hang, daisy chain, and power on and off the lights.
Active Grow also has the red bloom color lights and many other lights to choose from. I also like the free shipping from Amazon.
Click the button below to see more Active Grow LED lights and replacement bulb options.
Microgreen Light Recommendations
This article was written for those that are new to microgreens.
We will explain the terminology better in an upcoming article. If you haven't subscribed to our update list, you can do so below to be alerted when new content is published.
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To summarize our recommendations, if you grow a tray of microgreens here and there, use a sunny window, or a single fixture LED shop light like this one.
The one shown is 4-foot long, but you can search for 2- and 3-foot long shop lights. Box stores also carry these type of lights, but be sure to buy one listed at over 4,000K, preferably, 5,500 to 6,500K.
If you're looking to cover a couple of shelves, we recommend this 6-pack of LED lights from Barrina.
These lights are light-weight, provide plenty of light, and are very versatile as far as mounting. They also have individual on-off switches, so you don't have to have them all on at one time.
We grow the majority of our microgreens under these lights.
For those more serious, we recommend these Active Grow lights. One will work per shelf, they are easy to install, and have a lot of data backing their claims.
They have a YouTube channel that shows how well their lights perform.
We are believers in Active Grow Lights.
What Lights Do You Use?
This post is aimed at those new to growing microgreens, though we're sure many who have experience growing microgreens have read through the article.
If you are one of those people, please leave a comment below telling us what lights you use and why you like them.
There are so many lights on the market, it would be great to have other options.
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