Set up a staging server

I’m trying to seed test data on my staging server, but I get an error:

rake aborted!
Database commands are only supported in development environment

This is on a multisite setup, so the commands I’m running are:

./launcher enter web_only
ALLOW_DEV_POPULATE=1 bundle install
RAILS_DB=instance-x ALLOW_DEV_POPULATE=1 rake dev:populate

Which I’ve been using without issues so far, but now I get this error. Can I set an environment variable to allow database commands in production?