config(['app.timezone'=>''])不起作用

In my service provider boot() I have the following:

    config([
        'app.name' => 'Elephant',
        'app.url' => 'http://elephant.dev',
        'app.timezone' => 'America/Toronto',
    ]);

app.name and app.url both work fine, but app.timezone does not work. My configuration is NOT cached.

I'm saying it does not work because when I create() a record in the database, it is still using UTC for the created_at column and not America/Toronto.

Why is this happening and how to I make it work?

Make an environment variable in .env file

APP_TIMEZONE='America/Toronto'

and then in config/app.php set timezone to this

'timezone' => env('APP_TIMEZONE', 'UTC'),

If this is not solving the problem then just post in comment and I will delete the answer.