Choosing the best grow lights for seedlings and knowing how to use them can be overwhelming. When I first bought mine, I bought whatever was on sale and available. Although, turns out they were just what I needed!

If you start seeds, then you need a grow light. It will help you tenfold! I will break it all down for you in this post – why you need grow lights, how to use them, some recommendations for purchasing them, and of course, all the nitty-gritty in-between. Let’s dive in!

Why Use Grow Lights for Seedlings?

Using grow lights is super crucial for hardy seedlings. Seedlings need artificial light before they graduate and can go outside into natural light. But without proper training, they will fry in the harsh sunlight. 

Allowing seedlings to have artificial light will give your plants a better chance of survival when you bring them outdoors. 

Another benefit of using grow lights for seedlings is that you will prevent leggy seedlings. We’ve all been there and it sucks. Thankfully, it’s easy to prevent.

Since you are putting the grow lights close to the seedling, the seedling can now grow strong and tall because it is getting adequate light. If you were to put in too far (which we talk about later on) then the seed will stretch and try to get closer to the light and become weak.

Can I Use the Window Sill?

As mentioned above, using the window sill won’t give your plants the steady and reliable stream of light they need. They will become leggy and weak. So while that window sill looks enticing and you get a lot of sun, I would still advise on getting a grow light for seedlings.

LED vs Fluorescent Grow Lights

This is probably the largest debate when deciding on which grow light to purchase. While people still successfully use both kinds of lights, I am partial to LED but I’ll go through the pro and cons of each.

LED Grow Lights for Seedlings

LED stands for light emitting diodes and is measured in kelvins. The little diodes are flexible which means that the shape of the LED light can differ, which might suit your set-up.

PROS

• More energy-efficient
• Gives off more light, but no heat
• No health concerns
• No mercury
• It will last a very long time
• More options with light colours and spectrum

CONS

• Higher upfront cost 

Fluorescent Grow Lights for Seedlings

There are many different types of fluorescent lights such as high output, compact fluorescent, tubes, shop lights, etc. The most popular choice that people use for seeds is a T5 high output. 

Fluorescent lights come in different sizes such as t5, t8, and t12. The number measures the diameter of the lights, so the higher the number the less light power.

PROS

• Less expensive
• Easier to find

CONS

• Not as energy-efficient
• Won’t last as long as LED
• Give off more heat and are therefore a fire hazard
• Contains mercury 
• Known to be bad for your health
• Only one shape
• Not as powerful

Note: the incandescent lights found in your home will not be sufficient for growing seedlings.

What Colour Grow Light Should I Get?

Another popular question is what colour grow light to get. If you choose to go with fluorescent lights make sure to look for the kelvin rating which measures the colour of the lights. A rating between 5000 – 6500K will sufficiently mimic natural sunlight. 

Now if you do choose to go with LED light you can get full spectrum; this offers you a perfect balance of each of the red and blue lights which mimics the natural sunlight the best. The blue light promotes plant growth in the roots and leaves, while the red light promotes growth for fruiting plants.

You can also get white full spectrum LED lights if you don’t like the colours on your eyes.

What Plants Need a Grow Light?

While I’m not an expert in indoor decorative plants, I do know seedlings and all seedlings need a grow light. Technically, the seedlings don’t need the light put on them until they have emerged from the soil, but from then on all seedlings should have one hanging above them!

How Many Grow Lights Do I Need?

I like to have my grow lights on a shelf that is roughly 18″ wide by 24-30″ long. Each shelf has one tray of 72 cells that is approx. 11″ x 21″ so it fits perfectly. I think have 1 LED grow light per shelf. My grow light is 24″ long so it gives off the perfect amount of light.

How High Should I Hang My Grow Lights Above My Seedlings?

Once my seeds emerge and the lid is taken off, my LED grow lights have 2-3″ from the soil. The closer to the soil the better because it will prevent leggy seedlings. 

As your seedlings get older, you can continually move the grow light up. I would still recommend keeping the grow light at a min. of 4-10″ above the plant.

How Long Should I Leave My Grow Lights On?

The day your seedlings emerge from the soil is the day you should start with the grow lights. It’s important to keep the grow lights on for 12-18 hours a day, depending on whether you have fruit plants or leave greens. Buying a timer for the outlet will help you remember (and is a game-changer!!) 

Once the seedlings have grown, are over 4″ in height and have true leaves on them (and of course depending on what time of year it is) you can start the hardening-off process. This process allows the plant a break from the grow lights and is put outside for a few hours each day, increasing the time each day, so that the plant can prepare for its life outdoors. In that case, you won’t need the grow light anymore.

Best Grow Lights for Seedlings

The green one below was the first grow light that I bought 4 years ago, and it still works amazing. It is a full spectrum LED from Lights of America.

I recently bought the white one below and it’s a Fiet Electric full spectrum LED. I have yet to try it, but it was a decent price and it was available. 

I would look for something 24″ in length because it will fit a seed tray perfectly. 

My Grow Light Set Up

I like to use a shelf for my grow light set up. Doesn’t matter whether it’s wood, plastic or metal. Just some sort of shelf. I like to use the first 2 or 3 shelves for my grow lights and seed trays, and then the bottom shelf is for storage. 

I use bungee cords attached to the chains on the grow lights, so I can adjust the height easily. I love this set-up because everything is in one place and it doesn’t take up too much room!

To Sum It Up

Grow lights are totally essential to seed starting and if you haven’t invested in one, now is the time! Love to hear if you’ve used grow light before or have any questions in the comments below!