Need some help with this particular plant

Howdy!

I planted some beefsteak tomato seeds in late march, kept them under grow lights until I planted them outside on the 15th of May.

I have this plant in a 30 gallon raised bed, south facing balcony that gets plenty of light (my Park’s improved whopper, black Krim and blush tiger tomatoes are doing phenomenal)

Soil is a high quality garden bed mix, black kow manure, and a layer of cedar mulch on top. Mixed in a few tablespoons of 10-10-10 granular fertilizer when first planting

It feels like this plant has BARELY grown at all in the last month, while my other plants are thriving. I’ve been giving them 5-1-1 fish emulsion every 2 weeks (1-2 tablespoons/gallon), which doesn’t seem to make a difference for this particular plant. Does anyone have any tips to increase foliage growth? This particular plant has been the bane of my existence.

Zone 6B. I appreciate any and all responses, first time grower :) cheers!