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michael__ames

Nitrogen tie-up with 511, timing, or just variation?

michael_ames
7 years ago

This is my first year growing tomatoes from seed, and I'm a bit puzzled by some side-to-side comparisons.

  • All plants are of the same species (indeterminate, Jaune Flamme), germinated at the same time, and receive equal sunlight/cultural conditions on my south-facing open balcony and are fertilized regularly with FoliagePro.
  • Group A: I took the two healthiest seedlings and gave them the largest pots (15-gallon fabric pots) and the best soil (CRF'ed-and-limed 511 mix).
  • Group B: I ran out of 511 mix and large pots so the runt-of-the-seedling-litter got a smaller 7-gallon fabric pot with some crappy store potting soil (MiracleGro or HD Vigoro brand, can't remember).


Naturally I expected Group A to outperform Group B, but so far that hasn't been the case.

Group A did grow tall and strong stems early on, but since then hasn't grown much taller, produced fewer tomatoes and fewer leaves, and its foliage is healthy (disease and pest free) but rather light green. Here's a photo of two plants from Group A:

Group B has grown more, is much darker green, and has required constant vigilance to keep pruned and supported due to its vigor, despite small pot size and worse soil. Here's a picture of the plant in Group B:

I'm stumped here.

1. Is the problem my 511 mix? I did my best to remove sapwood from my aged/partially composted fir bark, and drainage is good. Perhaps I need to fertilize these in-511-plants more often, despite my use of additional CRF? I have been fertilizing Group A more often in the past 2 weeks, but haven't noticed a difference. Here's what the mix looks like (I used a mix of perlite and small lava rock):

2. Is planting time a factor? All of these plants were hardened off properly and permanently moved outside at the same time (April here in PNW), but Group A was transplanted into final large pots early; Group B remained in small pots about 2-3 weeks longer before final transplant.


I'm not complaining - all the plants are producing and reasonably healthy - just wondering why the 511+large-pot plants aren't beating out their disadvantaged siblings.

Any thoughts or other factors I should consider?

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