Differences in growth speed

I decided to start a makeshift "kitchen garden" close to the kitchen using a spare plastic tub I was going to recycle (previously used for home brewing beer). I am not sure about plastics overall, I'd imagine I will get cancer anyway, I am not a fan of them in general, especially microplastic, but oh well.

Anyway onto the main point. I sowed these basil seeds at the same exact time, the two in the pot, and the three plants on the right of the tub. The pot was placed  roughly at the back end of the tub, so they all got about the same amount of sunlight each day, save for the 30 minutes or so where the roof slowly exposes sunlight to all plants one after the other, that is negligible. The pot got basically the same amount of sunlight as any of the three tub plants.

Why in the world are the two potted basils growing so much faster than the other three in the tub? It's the very same soil, been checking water daily and the moisture content is about the same. The tub has many holes drilled in the side for aeration.

Any ideas?

If the seeds and soil are the same and you feel the soil moisture is the same, then I would check soil temperature.  If you have a pair of thermometers, put one in the pot and one in the larger tub and try to monitor the temperature across as much of the day as you can.  That may be part of the difference.....worth checking.

Soil temps were the same, I used a laser thermometer since it works perfectly with black surfaces (like soil).

What about container size? Is this giant container too big for herbs? Should I size all these herbs down so their roots can hit a wall and shoot downward?

I’m quite new to growing herbs.

Jeff Steez wrote:Soil temps were the same, I used a laser thermometer since it works perfectly with black surfaces (like soil).

What about container size? Is this giant container too big for herbs? Should I size all these herbs down so their roots can hit a wall and shoot downward?

I’m quite new to growing herbs.

Surface temps might be the same but the temp 4-6 inches down will make quite a difference.  Unless your growing season is extremely short, the difference is probably negligible.  I’ve found late crops can sometimes actually evade early pests.