Yeah, they're fine. Sheet rock mud is just clay (mostly).

Unless you use a two-bucket assembly (which some swear by), you will have to drill holes to let excess water out.

If you're new at this, spend some time learning about container growing. It isn't as easy as just shoveling some garden dirt into the bucket and plopping in the plant. The growing medium and watering practices are critical - especially with peppers.

Tell us more.

Dennis

Thanks for responding, Dennis! Actually, I have been doing both ground and containers gardening for many years. As I'm getting older and having some issues, I'm thinking about doing more gardening in containers than I have been doing. I got about 30 containers, mostly 4 and 5-gallons. last week I came across 12, 5-gallon containers of "Ready mix joint compound". On the label also indicating"GREEN Guard Indoor air quality certified, made in Charlotte, NC.
I checked on Google about the safety of growing vegetables in them and I didn't find much info.

I think the mud they make now is supposed to be pretty safe.
It used to have Asbestos in it and something else(I forget what).That was a lot of years ago when I was in construction...
Back then,asbestos was put in everything to increase durability.
Sheet rock and mud had it in it at the time.
I think that the stuff now doesn't even have a warning about eating the stuff on it-just a warning that if you stuff a baby in the bucket they could drown/die.

Read the warning label,if there isn't any warnings then the bucket should be cool to use.
All buckets I used had warnings printed on the bucket label.
If the buckets don't have the label,go check out your Homey Depote and read a couple different brands warnings.

I've used old cleaned out sheetrock mud buckets for growing in for years with no problems.

The asbestos that used to be added was outlawed in the late 1970's, and probably wouldn't affect plants grown in those containers anyway. When the mud was sanded asbestos fibers were released into the air which were breathed in. Those fibers could scar the lungs and do major damage.

Thanks to all responses. I can't wait to start growing my plants in about a month.

Mack

My partner a taper would wash out his buckets out in the yard sometimes and slush it into the gardens. Always reasuring it was good or at leadt wluld cause no harm.