Laravel日期验证文字“后”值

I have created a form request file which validates my start_date form input.

public function rules()
{
    return [
        'start_date' => 'required|date|after:2017-06-31',
    ];
}

I have placed a literal value in the after value, this however doesn't look like its working. Can someone advise the best way to do this?

Edit: This is the dump from my $request->all();

{
"_token": "tZa4e39ejrGHtrlpOYrUPfZ8PgSeD8FelY4voKni",
"start_date": "2017-07-01"
}

This is my form request validation:

public function rules()
{
    return [
        'start_date' => 'required|date_format:Y-m-d|after:2017-06-31',
    ];
}

I am using Laravel v5.4

The dates will be passed into the PHP strtotime function so change your date format to Y-m-d .

public function rules()
{
    return [
        'start_date' => 'required|date|date_format:Y-m-d|after:2017-06-31',
    ];
}