I've noticed this in commercial peppers, too. The ones sold in the grocery stores always have walls that are quite thick, but the ones sold in places run by local growers tend to be quite a bit thinner, maybe half as thick. I don't know if it's related to the variety or growing conditions or just the grading of the picked fruit. I'm curious about this, too.

I think that it is the variety plus growing conditions. From what I have been told in the past by an experienced gardener is that thin walls on thick walled peppers come from inadequate water. I tend to believe it because I no longer get thin walled peppers when they should be thick. Part of that may be not be how often the plants are watered but how much compost is in the soil to hold what water the plant does get. I plant my peppers in a lot of mushroom compost. It works quite well for me.

Christine

It's the growing conditions Ie; water, fertilizer, micro nutrients, sunlight, etc. A happy pepper is a thick walled pepper, thin walled peppers are just existing and doing their best under the condidtions you subject them to. I get great thick walled stuffing sized peppers from my 3 year old plants in 3 gallon pots.
Feel free to experiment with the conditions they grow in, it's the only way to learn what each plant needs to become robust.
Finally, keep a log of what changes you tried & the outcome from those changes.
Lou

FWIW there ARE thin-walled pepper varieties - like Cubanelles...

carolb,

The question the thread initiator asked was why his peppers grew making thin walls and NOT about the different thin-walled pepper varieties. You are answering to the replies and NOT to his original questions. I believe most of us are aware of the different varieties of peppers. We were answering to the possible causes that would make his peppers grow thin walled and made suggestions to help not arguments to hinder.

Lou

Begging your pardon - HydroPapa does not say what variety(varieties?) he's growing & asked whether that might be a factor ...

& I just realised he asked if time of harvest might be another factor & the answer is maybe yes - in many varieties, the younger the fruit, the thinner the flesh - IMPE