Last year was my first crack at growing seedlings without the benefit of a commercial greenhouse. In fact, it was the first time since I closed my greenhouse way back in 2000 that I have grown anything. My growing area was, and still is, an area set up in the north end of a metal pole building. This room is insulated and heated with electric baseboard heaters, has fluorescent office lights, and sports 3-18" by 5' windows. Needless to say, the conditions aren't ideal and after a decade absent from growing I was certainly a bit rusty. My first seedlings were tall, lanky, spindly, weak-stemmed, sickly specimens. And then damping-off ran its course.
Original Seedling Starter Stand
This year would be different. I identified multiple areas of concern in my seed starting stand and set out to correct them. First, the shelving system itself was lacking in sturdiness and this in turn limited flexibility regarding better lighting and heating options. I used scrap cedar fencing 2x4's to correct the structural shortcomings in building the 6' tall by 2' deep and 8' long carcass with shelf supports spaced at 18" intervals. I used 7/16" cdx plywood for the shelves.
Second, once the shelving was completed, I added small, screw-in hooks to the underside of the shelves to hold 2 sets of 4' shop lights per shelf. I found the shop lights on sale for less than $10 each. Rather than use expensive grow lights, I put 2 bulbs each with a different light spectrum in each shop light...same effect, considerably less money. The chains on the shop lights allow me to adjust each light to within a couple inches of the canopy of the plant growing beneath that particular light. Keeping the light in close proximity to the plant is critical in developing seedlings with strong, stocky stems. I added my home Christmas lights timer to the light circuit so that the lights are automated to provide 16 hours of light per day. Since each 4' shop light has a pull chain switch, I can turn on only the sections that are needed at any given time. I used an outlet strip rated at 1725 watts to plug all the lights into (the lights add up to about 1250 watts). The outlet strip is in turn plugged in to the timer.
Timer for Lights
Full or Partial Lighting
Third, I added heat 3 heat mats that can each handle 4 standard flats. The bottom heat is a must in speeding germination and also makes germination more uniform. These heat mats have a sensor that goes in the soil medium to control the temps. I am running all three mats off one sensor/thermostat so I have to use the same soil temp for all flats at the same time. I may have to add another thermostat to allow different temps for different seeds but for this year we'll see how an "average" temp works.
Germination Shelves in Use
This germination system will be a huge benefit in providing a better growing environment for my seedlings.