administrate: Invalid date error

I have a Post model with these attributes:

create_table :posts do |t|
      t.date :date
      t.text :rationale

      t.timestamps
end

date field is of type ‘date’ (Postgresql database) After entering /admin/posts I get an error:

Showing /home/jedrek/.rvm/gems/ruby-2.3.0/gems/administrate-0.8.1/app/views/fields/date_time/_index.html.erb where line #20 raised:

invalid date

  #   "12/13/2012".to_date # => ArgumentError: invalid date
  def to_date
    ::Date.parse(self, false) unless blank?
  end

  # Converts a string to a DateTime value.

gem ‘administrate’, ‘~> 0.8.1’ Rails 5.0.5

I know for sure that it worked fine in gem “administrate”, “~> 0.2.2”