No-fail seed starting method

After a few years of trial and error, I’ve come up with what I’d like to think of as the no-fail seed starting method. I know, a promise not to fail at a gardening endeavor is kind of risky.  But I think if you try this method you should have a great deal more success germinating seeds and growing healthy plants than you would with other methods, such as putting the seeds in a “sunny window.” Of course, this is assuming you have good seed. Seed starting with grow light.

This is a low-cost method of setting up a seed starting operation that you can use for years. How low-cost? Less than $100–and it will last for years.

In this article I use a four foot shop light suspended over top of the plants. There are other lighting options depending on how much you want to spend. This is the cheapest way I’ve found to set up a no-fail seed starting operation.

Materials needed:

For frame to suspend grow light:

Nails or screws

2-2X4 by 8’ pine lumber

15” by 52” plywood

1-2” X 2” X 52” pine lumber

Light weight chain (to suspend the shop light)

48” long fluorescent shop light

Seed starting equipment:

Heat mat specifically for seed starting (from $25-$50)

11” X 16” cookie sheet

Seed starting tray with dome

Shallow (1/1/2 inch deep) container for germinating seed with holes in the bottom for drainage

Brand name germination mix such as Sun-Gro, Pro-mix, Bacto (not potting soil). Jiffy also sells a mix specifically for germinating seeds at a cost of about $5.00.

For more information on seed starting, check out Nancy Bubel’s classic seed starting book.

Step 1: Build a frame using the materials mentioned above to suspend a shop light (like the one below) or other type of lighting fixture over the plants using light weight chains. The bottom frame is 52″ long, by 15″ wide. The plywood bottom is 15” by 52,” the vertical supports are 15” tall and the 2 by 2 is 52” long.

Step 2: Moisten the seed starting mix by adding one part water to three parts germination mix. The mix should be moist but not dripping wet.


Step 3: Fill the shallow container(s) with the mix, tamping it lightly to firm it in.

Step 4: Plant the seeds of your favorite crop or flowers, following the recommendations for planting depth. Seeds can be spaced fairly close since they’re going to be transplanted after they get their true leaves. Firm the seeds in nicely to ensure good contact with the growing medium.

Step 5: Place your heat mat in the frame and put a cookie sheet over the heat mat to ensure that the mix is not getting too hot, causing the mix to dry out (note: this framed is actually large enough to fit two heat mats in if you have a lot of seeds to germinate. 

Step 6: Place a clear dome over the tray and place on the heat pad.

seed starting

Step 7: It is critical that the germination mix stays moist, but not soggy during the germination phase. Spritz with water once or twice daily and bottom water with room temperature water about every three days.
Step 8: When the seed leaves (cotyledons) begin to appear and it looks like most of the seeds have germinated, lower the fluorescent light within about 4” of the seedlings. When true leaves appear, start a regimen of water, let dry out slightly, and water again. Fertilize with a weak solution of soluble fertilizer.

Step 9: When the seedlings develop true leaves, transplant to pots or cell packs. I usually transplant my tomatoes and peppers to cell packs (6 cell packs to a flat for a total of 36 flats. Remove the seedlings by loosening up the roots and gently grabbing hold of the leaves (not the stems) and pulling out the plant.

Step 10: Bottom water the seedlings in the cell packs using the water-let dry out method. Harden off by allowing them to be outside for a few hours at a time each day before setting them out permanently.

Seed starting with grow light.

This entry was posted in Neil Moran, northern gardening, Uncategorized and tagged , , . Bookmark the permalink.

2 Responses to No-fail seed starting method

  1. Rebecca says:

    Great. Thanks Neil. I purchased the heat mats but not a domed tray. These instructions are clear and easy. I am looking forward to spring thaw!

Leave a Reply

Your email address will not be published. Required fields are marked *