diff --git a/src/octoprint/plugin/__init__.py b/src/octoprint/plugin/__init__.py
index a8736c4c..bab1350a 100644
--- a/src/octoprint/plugin/__init__.py
+++ b/src/octoprint/plugin/__init__.py
@@ -145,7 +145,7 @@ def plugin_settings(plugin_key, defaults=None, get_preprocessors=None, set_prepr
 
 	Arguments:
 	    plugin_key (string): The plugin identifier for which to create the settings instance.
-	    defaults (dict): The default settings for the plugin.
+	    defaults (dict): The default settings for the plugin, if different from get_settings_defaults.
 	    get_preprocessors (dict): The getter preprocessors for the plugin.
 	    set_preprocessors (dict): The setter preprocessors for the plugin.
 	    settings (octoprint.settings.Settings): The settings instance to use.
@@ -180,13 +180,12 @@ def plugin_settings_for_settings_plugin(plugin_key, instance, settings=None):
 		return None
 
 	try:
-		defaults = instance.get_settings_defaults()
 		get_preprocessors, set_preprocessors = instance.get_settings_preprocessors()
 	except:
-		logging.getLogger(__name__).exception("Error while retrieving defaults or preprocessors for plugin {}".format(plugin_key))
+		logging.getLogger(__name__).exception("Error while retrieving preprocessors for plugin {}".format(plugin_key))
 		return None
 
-	return plugin_settings(plugin_key, defaults=defaults, get_preprocessors=get_preprocessors, set_preprocessors=set_preprocessors, settings=settings)
+	return plugin_settings(plugin_key, get_preprocessors=get_preprocessors, set_preprocessors=set_preprocessors, settings=settings)
 
 
 def call_plugin(types, method, args=None, kwargs=None, callback=None, error_callback=None, sorting_context=None):
@@ -315,11 +314,12 @@ class PluginSettings(object):
 		self.settings = settings
 		self.plugin_key = plugin_key
 
-		if defaults is None:
-			defaults = dict()
-		self.defaults = dict(plugins=dict())
-		self.defaults["plugins"][plugin_key] = defaults
-		self.defaults["plugins"][plugin_key]["_config_version"] = None
+		if defaults is not None:
+			self.defaults = dict(plugins=dict())
+			self.defaults["plugins"][plugin_key] = defaults
+			self.defaults["plugins"][plugin_key]["_config_version"] = None
+		else:
+			self.defaults = None
 
 		if get_preprocessors is None:
 			get_preprocessors = dict()
@@ -345,14 +345,14 @@ class PluginSettings(object):
 			return result
 
 		def add_getter_kwargs(kwargs):
-			if not "defaults" in kwargs:
+			if not "defaults" in kwargs and self.defaults is not None:
 				kwargs.update(defaults=self.defaults)
 			if not "preprocessors" in kwargs:
 				kwargs.update(preprocessors=self.get_preprocessors)
 			return kwargs
 
 		def add_setter_kwargs(kwargs):
-			if not "defaults" in kwargs:
+			if not "defaults" in kwargs and self.defaults is not None:
 				kwargs.update(defaults=self.defaults)
 			if not "preprocessors" in kwargs:
 				kwargs.update(preprocessors=self.set_preprocessors)
diff --git a/src/octoprint/server/__init__.py b/src/octoprint/server/__init__.py
index b90ab21e..14009965 100644
--- a/src/octoprint/server/__init__.py
+++ b/src/octoprint/server/__init__.py
@@ -245,7 +245,14 @@ class Server(object):
 			return props
 
 		def settings_plugin_inject_factory(name, implementation):
-			"""Factory for additional injections depending on plugin type"""
+			"""Factory for additional injections/initializations depending on plugin type"""
+			if not isinstance(implementation, octoprint.plugin.SettingsPlugin):
+				return
+
+			default_settings_overlay = dict(plugins=dict())
+			default_settings_overlay["plugins"][name] = implementation.get_settings_defaults()
+			self._settings.add_overlay(default_settings_overlay, at_end=True)
+
 			plugin_settings = octoprint.plugin.plugin_settings_for_settings_plugin(name, implementation)
 			if plugin_settings is None:
 				return
@@ -272,7 +279,8 @@ class Server(object):
 
 			implementation.on_settings_initialized()
 
-		pluginManager.implementation_inject_factories=[octoprint_plugin_inject_factory, settings_plugin_inject_factory]
+		pluginManager.implementation_inject_factories=[octoprint_plugin_inject_factory,
+		                                               settings_plugin_inject_factory]
 		pluginManager.initialize_implementations()
 
 		settingsPlugins = pluginManager.get_implementations(octoprint.plugin.SettingsPlugin)
diff --git a/src/octoprint/settings.py b/src/octoprint/settings.py
index 23f03066..d5f8dd2e 100644
--- a/src/octoprint/settings.py
+++ b/src/octoprint/settings.py
@@ -829,8 +829,12 @@ class Settings(object):
 			self._migrate_config(config)
 		return config
 
-	def add_overlay(self, overlay):
-		self._map.maps.insert(1, overlay)
+	def add_overlay(self, overlay, at_end=False):
+		if at_end:
+			pos = len(self._map.maps) - 1
+			self._map.maps.insert(pos, overlay)
+		else:
+			self._map.maps.insert(1, overlay)
 
 	def _migrate_config(self, config=None):
 		if config is None: