Have you successfully used this fertilizer in the past? It is highly questionable quality. Plus it is dry granular organic components so the nutrients are only available to the plant once they are digested by the soil food web. That takes time.

They are suffering from lack of nutrients. Feed them and use a quick fix liquid.

Dave

Probably (my guess) the soil is still cold and the roots are not taking up Phosphorus and other nutrients. This is normally a seedling stage issue but it can happen to young plant too. Yesterday I was at HD, just looking around. Almost all Burpee and Bonnie plants were purple. I know why. The plants are in small pots , outside and the temperatures drop to low 40s at night and the day temperature have been on the cool side lately.

I see other issue with your plants : Leaf Edema The bumps) .

That is because of MAYBE(?) too much watering !

JMO

Sey

Agree with Sey. Purple leaves are usually a giveaway about phosphorus deficiency. Though I thought that purple only appeared on the undersides of leaves in that case. Overly cold temps can do that as well, though the plants will grow out of it when the weather warms.

Thank you for the advice. I will try some liquid fertilizer and see if things perk up and keep an eye on them over the next few days.

Yes, liquid fertilizer is like sugar for us, quick energy source. Other nutrients in the soil or organics might not be readily available to the roots.

Sey