1) If you can use two shop lights per self. I mount them together on a board so I and raise and lower them together.
2) Most seeds do not need light to sprout. So I may not use light till first seeds sprout.
3) Once seeds sprout I lower the lights and keep them four inches from the top of sprouts.
4) I create a plastic lined area under each light so I can flood with warm water and drain. This allows quick soak of trays and draining. It also prevents salt buildup.
5) I use cool light and soft white bulbs in light if full spectrum is to expensive.
6) A propagation mate may be needed for seeds that need higher temps than the room you keep them in. Sometimes it is easy enough to keep the room at the right temperature range.
Remember water evaporating lowers temperature some. So if the room is too cold the seed trays are likely a few degrees cooler.
I have a large table that is in my basement. I ducked taped rolled up newspagers around the edges to make a raised area around the edges. I put a waterbed heater in the middle of the table.
I than covered the table with half of a water bed mattress that I recycled. I have a drain tube with shut off valve on one end. I put a inch to two inches of water on the table and put my seed trays in it.
I have several shop lights on a board frame. I can raise or lower this frame over the table.
So I plant my seeds, put them in the water on the table, adjust my water level after the seeds have soaked and turn on the heater.
When the seeds sprout I lower the light to four inches from the tallest seedlings and run it on a timer to force grow with extra light.
I replace water as needed and raise light as needed. Otherwise I just let plants grow till they are ready to repot and move to cold frames.
Joel Salatin has signs on his property that say "Trespassers will be Impressed!" Impressive tiny ad:
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