I've started a few flats of french marigolds every year without a problem. This year a lot of them are showing:

* dark speckles -- tiny maybe 1/32" across (under 1 mm)

* purple black edges on some leaves.

* slightly darker green than unaffected plants.

On another forum someone suggested that my pH was too low, and that I had iron toxicity. I've since checked that, and the water dripping from a freshly watered pot runs 7.4.

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