Monday, March 25, 2013

How to create an indoor veggie grow lighting system

"Gardens are a form of autobiography." - Sydney Eddison

Gardening is in my blood.  Long ago, my maternal ancestors migrated from Europe to the Pacific Northwest -- to farm.  Fast forward to the 60's and..... I have great memories of 5-year-old me, using my tiny hands to help my maternal grandmother pick and snap fresh green beans to be boiled with freshly harvested potatoes and Walla Walla sweet onions.    My paternal grandparents were also dedicated farmers by profession.  Needless to say, I have an innate need to watch those seeds sprout and their first little leaves punch thru the soil as if to say, "Here I am. BRING it on!" 

Hello Spring!  Bring it on!
I am the raddish!  Koo-koo-koo-choo!

Of course, few things are more rewarding than eating what you've grown yourself.

Our growing season in Western Washington is relatively short so I like to start things indoors.  One year after researching overly expensive and/or cheaply constructed grow lighting systems, I decided to devise a better solution. Here's my recipe so you can do the same if you'd like.  My up-front costs were about $250, which accommodated a whole lot of plants, is easily updateable and may last generations.

How to create an indoor grow lighting system.

  • 1 FOUR FOOT LONG wire shelf rack set.  Costco has a great one on sale for $90.  The Costco one is designed for indoor-outdoor use, which is a nice convenience for hardening off your plants.  The great thing about the wire shelf units is that the vertical supports are typically in two pieces and all shelves are adjustable, so you can grow or shrink your shelf height and number of shelves as you desire.  Any wire wrack shelf set will work as long as it is FOUR Feet LONG to facilitate the shop lights.  FOUR FEET LONG!!!! Did I say that enough times?
  • 2 4-foot T-8 shop lights per shelf for as many shelves as you want to use.  I like the Lithonia Diamond Plate Reflective fixtures from Home Depot because they have reflective metal on the inside nearest the bulbs and their tube sockets are flared out.  Both of these features optimize the lighting that reaches your plants.  But you can use any cheap shop lights you want.  I bought 4 shop lights and they served my rather huge tomato grow operation very well.
  • Fluorescent tubes.  Debate rages on the internet regarding whether grow lighting is better, whether T5 is better than T8 lighting.  Suffice to say that I had incredible luck with Sylvania 5000K 32 watt T-8 "natural light" household tubes which sold for something like $3-5/ea.  These provide full-spectrum lighting, thus, all the colors the plants need. 
  • A power strip if you have multiple shop lights.
  • A vacation timer, the kind that turn lights on and off at particular times.  You don't need anything fancy, just something that does the job.  If you don't have one hanging around the house, typically Home Depot/Lowes sells them for $8.  And you really don't need this if you have a good memory for turning lights on and off (I don't).  You DEFINITELY don't need a fancy grow timer (unless you have one already).
  • Grow pots, soil, seeds.  I typically use peat pellets to start things because I can put lots of them in a small space, minimizing how much light I need at first.  I then transplant to generic plastic cups and then into larger pots that I've saved from transplanting outdoor plants (see pictorial below).  One year, I bought several of the Jiffy Peat Pot kits that come with peat pellets and drainage trays, and I have enough peat pots to last for years.  The seeds I've tried include tomato, lettuce and raddish.  I suspect any leafy green will grow.   Flowers are a subject for another post (with the caveat that my tomatoes did produce flowers indoors.)
  • A seedling heating mat.  This is optional, but it definitely speeds germination.  You can buy these in varying sizes, but a 9x24 size worked great for me. I've heard of people putting seedlings on top of the fridge for warmth, etc. but it's nice to have something that is location-independent.
  • Aluminum foil or other reflective material (optional) to "trap" light.
I will provide details on setup, but first, here is a picture of my fully configured setup with plants.  It isn't pretty, and thus it's a great addition to a basement, spare bedroom, or other hiding place, LOL. But it's exceedingly practical.  No construction skills needed AT ALL.  Trust me on this.  Note that the fluorescent lighting isn't hanging evenly. This is intentional.  Hanging the lights unevenly accommodates larger and smaller plants.  As you can see, my plants are really, really happy.

  • Set up the wire shelves according to directions. 

!!!!BIG RED NOTE!!!!
You will be using the S-hooks and chains that are included with your shop lights to hang the shop lighting to the wire shelf above your plants, so adjust one or two of your shelves to a height where you can hang the shop lights within one or two inches of your plant height even for new seedlings.

  • Install the shop lights using the s-hooks and chains provided with your shop lights as pictured.  Keep in mind that the lighting will have to be adjusted LOW enough so that the fluorescent tubes are just a few inches above the plants (at least at first), so as stated before, the shelf height and chain length need to accommodate this.

  • Install the fluorescent tubes into the shoplight fixtures, making sure they're seated well in the fixtures.

  • Plug the shop light fixtures into your power strip and the power strip into the vacation timer. You actually don't have to turn the light on until the seeds germinate.  Once germination occurs I've found that programming 16 hours of light and 8 hours of darkness into the vacation timer works very well.  Besides saving energy, darkness is important to plants for forming stocky stems.

  • Plant your seeds in Jiffy peat pots on drainage trays.  (These drainage trays with peat pellets are sold online at Amazon, but they are much less expensive at home improvement stores).  Place the (optional) heat mat on a shelf and place the seed trays on the heat mat under a light.  (Don't plug the heat mat into the vacation timer).  With heat mat, germination should occur in about 3 days.  Once germination occurs, you can remove the heat mat.

  • Once germinated, put the seedlings under the grow lighting, one or two inches from the fluorescent tubes.  As seedlings grow, adjust the lighting up using the chains and s-hooks you used to hang the lighting.

  •  Transplant to larger pots as needed as your plants grow.  Apply aluminum foil to the shelves to "trap light" from getting "lost" thru the shelves, sides, etc.

  •  Harden off your plants as needed for final planting outdoors.

My results (from a year ago).  I wish I had better pics, but I didn't know I would be doing a blog entry ;-).

First germination in peat pot. This is lettuce:

Lettuce transplant day

Tomato transplant day:

Lettuce nearly ready to be thinned.

First tiny harvest of lettuce thinnings.  The harvests got a WHOLE LOT bigger after this thinning:

Tomato ready to go into a bigger pot.

Transplant to bigger pots done.  A cart is also nice for hardening off right before planting outdoors:


Just before final transplant to outdoor pots.  This plant was grown almost entirely indoors (with mere hours outdoors to harden off).  We had a very cold spring and late summer, so these babies didn't get to go outdoors until late June.

One final tip:  Give lots of plants away or learn how to "cull" what you have remaining.  Don't be like us, else you may lose your precious puppy dog in the tomato jungle.

And yes, as you can see, we grew our plants entirely in pots even outdoors!  Take a 5 gallon Lowe's bucket, cut drainage in the bottom, add potting soil and plant, et voila!  Jungle.




  1. Very good instructions. I did someting similar a few years back. I upgraded it to have a four-foot 8-tube T5 light fixture after a few years of using standard T12 shop lights. The growth is amazing.

  2. Thanks for writing. Yes, growth is amazing. The reason I chose T8 over T5 is that the lumens per watt efficiency is about the same between T5 and T8 tubes. The nice thing about T5 tubes is that you can fit more in a space because they have smaller diameters so you can get more lumens per sq/in. But I also found that I didn't need more than 4 tubes per shelf, so T8 was the sweet spot. At the time I bought my fixtures, T8 was MUCH less expensive than T5 so the T8s made more sense cost-wise too ;-). But T5s are slowly coming down in price.

  3. This is possibly the best looking setup I have seen. I am actually looking to use this to start an indoor herb garden on one shelf, tomato starting shelf for the spring, and a germinating hardy hibiscus plant shelf. Thank you so much for this setup it is so much more reasonable than other solutions and seems like the best option for indoors!

    1. I am delighted to hear that my idea was helpful. Also, I saw that has the indoor/outdoor plant shelves on sale again for $90 or so? You might want to pick one up while you can! Enjoy your future indoor garden and drop me a line and let me know about your success!