Well, there is a clear winner in my soil medium test, and it was not the product I expected.
The contenders
You’ll recall that in my original post where I described transplanting mass-planted tomato seedlings, I was transplanting six Cherokee Purple seedlings into larger pots and decided to test the two mixes I had head to head. I had Miracle Gro Moisture Control Potting Mix and Burpee eco-friendly Organic Seed Starting Mix:
I could tell from the beginning that the Miracle Gro did seem to hold water better than the Burpee when I transplanted on April 6:
I planted out the tomatoes:
These have been inside for a total of about 7 days over the past 21 days while we had two frost warnings and several days that were down in the thirties at night. They had poor lighting while indoors (note to self: use the grow light of you have to bring in hardened off seedlings), but I’ve kept them watered as needed.
Just six days later there was a clear lead:
Plants in Burpee mix on the left are clearly larger on April 12 
Top view. Miracle Gro is the darker soil with the bark-looking chunks
(Apparently I moved the plant sign from one side to another. But you can tell the Burpee from the Miracle Gro even when it’s damp because the Burpee has the little coconut hairs in it and the Miracle Gro has chunks that look like bark and move up to the surface as you water)
The winner
I waited a few more days to see if there’d be a change in growth over time, but the Miracle Gro seedlings never caught up to the seedlings in Burpee’s mix, even with the low light that made the plants grow tall and spindly:
Burpee in rear 
Burpee on left 
April 25, Burpee is the clear winner
So after 19 days, I can definitely say that Burpee’s eco-friendly Natural and Organic Seed Starting Mix is the clear winner in my contest. I was surprised, honestly, because my dad always used Miracle Gro, and I always assumed it was just the best, but this test has converted me to Burpee. My friend, Dawna, who is a master gardener and who runs the garden department at our local Lowe’s recommended the Burpee mix, and I sent her these pictures. Even she was surprised at how well the Burpee mix performed.
I’ll check when I plant these to see if there’s a marked difference in root formation and update this post accordingly, but I don’t expect to see one.
Fertilizer stats
For you gardening nerds, here are the NPK stats for the fertilizer found in each medium:
Burpee organic – 0.06 – 0.03 – 0.03 NPK
Miracle Gro – 0.21 – 0.11 – 0.16 NPK
