what is wrong with my pepper seedlings?

Question

3 of my bell pepper plant seedlings have yellow leaves and I don’t know what’s wrong. They are in jiffy seed start mix with 2 teaspoons of Jobe’s organic vegetable fertilizer near the bottom of the cup. My other bell pepper turned out fine — it’s just these 3.

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Answer 1

This article should help:
https://www.gardeningknowhow.com/garden-how-to/propagation/seeds/seedlings-turning-yellow.htm