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How to Start Seeds Indoors With an Easy DIY Seed-Starting Rack
One of the questions I get asked most often about seed starting is, “Can I start seeds in front of a window?”
Although it sounds like an easy way to start seeds – it’s nearly impossible to grow healthy seedlings in front of a window, especially during winter and spring when the days are short, and the sun is weak.
Seedlings need strong, overhead light.
And what happens when they don’t get it?
They struggle and become leggy (spindly and stretched out). And that’s a bad thing.
Healthy seedlings are strong, short, and stocky.
They’re much more likely to withstand everything Mother Nature will throw at them.
Growing your seedlings under lights is the best way to make sure they’ll thrive when you set them outside.
I’ve been gardening for more than 20 years, and have my seed starting system down to a fine art. And it all starts with a good seed-starting/grow-light stand.
Keep reading to discover how easy it is to create your own grow light stand – no carpentry required!
I recommend adjustable wire shelves (with wheels) for your seed starting setup.
What I love about these shelf units:
- They’re sturdy.
- They’re easy to assemble. They only take about 30 minutes to put together – the only tool you’ll need is a rubber mallet.
- They’re easy to move because they have wheels.
- You can fit up to four 10″ x 20″ trays on each shelf!
- When you’re not starting seeds on them you can use them for storage or as a drying rack for herbs or a curing rack for garlic and onions.
The first thing to decide is how deep of a shelf unit to purchase.
You have two choices, 1.5′ deep, or 2′ deep.
If you have the floor space and budget for the 2′ deep shelves and lights, it’s the better investment because you’ll get more light coverage on your seedlings.
Wire shelf unit: 1.5′ x 4′ x 6′
- Pros: Less expensive and has a small footprint.
- Cons: Because the lights that fit this shelf don’t fully cover a 10″ x 20″ tray, the seedlings on the ends of the flat can get a little leggy.
- Plan to spin your trays regularly so they get more evenly lit.
- This setup also works best when you can place the shelves next to a wall that you’ve covered with mylar – this helps to bounce more light back onto the seedlings. If you can’t put your stand next to a wall, choose the 2′ x 4′ shelves.
- The other thing you can do is put only two trays on each shelf, end-to-end, but this cuts the number of seedlings you can grow in half!
Wire shelf unit: 2′ x 4′ x 6′
- Pros: Even light for your seedlings. The 6-tube lights you’ll use with this setup give excellent light coverage for 10 x 20″ trays.
- Cons: The shelves take up more floor space and the shelves and lights are more expensive.
Shop for supplies: Shelf unit
Once you’ve chosen your shelves, the next thing to do is choose your lights.
I recommend fluorescent lights from Hydrofarm. They’re reliable and relatively inexpensive.
I’ve used them for years and have always been happy with them.
They also have a “designer” series, which has a bronze finish, if you don’t like the look of the white fixtures.
LED grow lights are another option, but be aware that you generally need to keep LED lights far away from the plants (20 inches or more) which means your seed starting setup will take up a lot more floor space.
The size light(s) you choose depends on the shelving unit you’re using.
- The 4-bulb fixtures fit the 1.5′ x 4′ shelves.
- The 6-bulb fixtures fit the 2′ x 4′ shelves.
- But if you hang one light from the ceiling, and use the top shelf to grow plants, you can use one 6-bulb fixture with the 1.5′ x 4′ shelf unit.
Another option is to use two 2′ x 2′ fixtures on one shelf. This gives you more flexibility.
- You can start 2 flats under one light, and not have to turn an entire 4′ fixture on.
- Or start flats at very different times and raise and lower the heights of the two lights independently.
Shop for supplies: 4-bulb lights (fit the 1.5′ x 4′ shelves)
Shop for supplies: 6-bulb lights (fit the 2′ x 4′ shelves)
Accessories for Grow Light Stand DIY Setup
Adjustable light hangers
You need a secure way to hang your lights on the shelf unit. The best thing to use for this are ratchet hangers that are designed to support plant lights.
They’re easy to use and will support the weight of heavy lights.
A common alternative is to use chain and S-hooks, but these can be finicky and require you to unhook the light to move the light up or down, which is just asking for trouble! You don’t want all your hard work to be destroyed by one slip of the finger.
These ratchet hangers make raising and lowering the lights a pleasure rather than a chore.
You’ll need one pair per light fixture.
Besides growing your seedlings under lights, the other critical item that’ll ensure you grow healthy seedlings is an oscillating fan.
I can’t stress enough how important air movement is for seedling health!
An inexpensive fan pointed at each of your shelves will cut down on diseases like damping off and make your seedlings grow stronger.
The type of fan you can use depends on your setup.
I have a second set of shelves across from my plants that I clamp my fans to and point directly at the plants.
You could also set a tabletop fan on a shelf unit that’s next to your plant stand.
You may need to get creative if you don’t have anywhere to set a fan.
- One thing you could do would be to clamp a small fan on one side of each shelf and sacrifice some flat space to the fan.
- Another idea is to get a long tension rod that is long enough to go from floor to ceiling, and clamp fans to it.
You’ll need one fan per shelf.
Shop for fans
Since your plants need some darkness each day, you’ll need to set your light(s) on a timer.
You’ll also want to put your fan(s) on a separate timer.
The next thing you want to make sure you do is to protect all of your seed-starting equipment from electrical surges.
A surge suppressor is a good insurance policy against losing all of your equipment because of some power weirdness.
A heat mat is optional but will help your seeds germinate faster.
- Unless you plan to start hundreds of plants at once, one heat mat should be enough.
- If you get a heat mat, I highly recommend getting a heat mat thermostat with it.
- It’ll turn your mat on an off automatically and keep your soil at a more even temperature.
- You can fit two 10″ x 20″ flats on one mat.
Shop for a heat mat & thermostats
Using a heat mat:
If you plan to put your seed-starting rack next to a wall, covering the wall with mylar is a good idea.
- It’ll bounce light back onto your seedlings better than paint.
- It’ll protect your wall from water splashes and dirt.
- And, if you chose to go with the 1.5′ deep shelves, it’s helpful to bounce all the light you can back onto your plants since 4-bulb lights that fit those shelves don’t cover the trays as well as the 6-bulb lights.
Your turn: Tell me about your grow light stand DIY…
Have you grown plants inside under lights? How did it go?
Leave a comment below!
Hi, I'm Cheryl. I'm a certified gardener, bird lover, and spreadsheet enthusiast. I believe that with a few smart strategies and a little know-how, you can grow your dream garden and still have time to enjoy it. I teach online gardening courses and write articles that help you save time and money in your garden.
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