diff --git a/docs/client.rst b/docs/client.rst
index c1d1bfed..50f27bab 100644
--- a/docs/client.rst
+++ b/docs/client.rst
@@ -65,6 +65,11 @@ Flask config by the key ``TWITTER``, the configuration looks like::
 
     oauth.init_app(app)
 
+Or looks like that::
+
+    app.config['TWITTER_CONSUMER_KEY'] = 'a random string key'
+    app.config['TWITTER_CONSUMER_SECRET'] = 'a random string secret'
+
 Twitter can get consumer key and secret from the Flask instance now.
 
 You can put all the configuration in ``app.config`` if you like, which
diff --git a/flask_oauthlib/client.py b/flask_oauthlib/client.py
index fc21d0c4..6171228b 100644
--- a/flask_oauthlib/client.py
+++ b/flask_oauthlib/client.py
@@ -297,10 +297,18 @@ def _get_property(self, key, default=False):
                 return default
             return attr
         app = self.oauth.app or current_app
-        config = app.config[self.app_key]
-        if default is not False:
-            return config.get(key, default)
-        return config[key]
+        if self.app_key in app.config:
+            # works with dict config
+            config = app.config[self.app_key]
+            if default is not False:
+                return config.get(key, default)
+            return config[key]
+        else:
+            # works with plain text config
+            config_key = "%s_%s" % (self.app_key, key.upper())
+            if default is not False:
+                return app.config.get(config_key, default)
+            return app.config[config_key]
 
     def make_client(self, token=None):
         # request_token_url is for oauth1
diff --git a/tests/test_client.py b/tests/test_client.py
index 1c8468eb..db7e820f 100644
--- a/tests/test_client.py
+++ b/tests/test_client.py
@@ -114,6 +114,25 @@ def test_lazy_load(self):
         assert twitter.authorize_url == 'auth url'
         assert twitter.content_type is None
 
+    def test_lazy_load_with_plain_text_config(self):
+        oauth = OAuth()
+        twitter = oauth.remote_app('twitter', app_key='TWITTER')
+
+        app = Flask(__name__)
+        app.config['TWITTER_CONSUMER_KEY'] = 'twitter key'
+        app.config['TWITTER_CONSUMER_SECRET'] = 'twitter secret'
+        app.config['TWITTER_REQUEST_TOKEN_URL'] = 'request url'
+        app.config['TWITTER_ACCESS_TOKEN_URL'] = 'token url'
+        app.config['TWITTER_AUTHORIZE_URL'] = 'auth url'
+
+        oauth.init_app(app)
+
+        assert twitter.consumer_key == 'twitter key'
+        assert twitter.consumer_secret == 'twitter secret'
+        assert twitter.request_token_url == 'request url'
+        assert twitter.access_token_url == 'token url'
+        assert twitter.authorize_url == 'auth url'
+
     @patch(http_urlopen)
     def test_http_request(self, urlopen):
         urlopen.return_value = Response(