diff --git a/lib/dependency-manager-adapters/workspace.js b/lib/dependency-manager-adapters/workspace.js
index d251b949..88d299c3 100644
--- a/lib/dependency-manager-adapters/workspace.js
+++ b/lib/dependency-manager-adapters/workspace.js
@@ -18,15 +18,6 @@ module.exports = CoreObject.extend({
     if (!this.useYarnCommand) {
       throw new Error('workspaces are currently only supported by Yarn, you must set `useYarn` to true');
     }
-  },
-
-  packageJSON: 'package.json',
-
-  setup(options) {
-    if (!options) {
-      options = {};
-    }
-
     let packageJSON = JSON.parse(fs.readFileSync(this.packageJSON));
     let workspaceGlobs;
 
@@ -59,6 +50,15 @@ module.exports = CoreObject.extend({
       });
     });
 
+  },
+
+  packageJSON: 'package.json',
+
+  setup(options) {
+    if (!options) {
+      options = {};
+    }
+
     return RSVP.all(this._packageAdapters.map(adapter => adapter.setup(options)));
   },
 
diff --git a/test/dependency-manager-adapters/workspace-adapter-test.js b/test/dependency-manager-adapters/workspace-adapter-test.js
index 5422b63f..2c794f5f 100644
--- a/test/dependency-manager-adapters/workspace-adapter-test.js
+++ b/test/dependency-manager-adapters/workspace-adapter-test.js
@@ -195,6 +195,29 @@ describe('workspaceAdapter', () => {
   });
 
   describe('#cleanup', () => {
+    it('works without having called #setup first', () => {
+      fs.ensureDirSync('packages/test/node_modules');
+
+      writeJSONFile('packages/test/package.json', { originalPackageJSON: false });
+      writeJSONFile('packages/test/node_modules/prove-it.json', { originalNodeModules: false });
+
+      let workspaceAdapter = new WorkspaceAdapter({
+        cwd: tmpdir,
+        useYarnCommand: true,
+        run: () => Promise.resolve(),
+      });
+
+      fs.ensureDirSync('packages/test/.node_modules.ember-try');
+
+      writeJSONFile('packages/test/package.json.ember-try', { originalPackageJSON: true });
+      writeJSONFile('packages/test/.node_modules.ember-try/prove-it.json', { originalNodeModules: true });
+
+      return workspaceAdapter.cleanup().then(() => {
+        assertFileContainsJSON(path.join(tmpdir, 'packages/test/package.json'), { originalPackageJSON: true });
+        assertFileContainsJSON(path.join(tmpdir, 'packages/test/node_modules/prove-it.json'), { originalNodeModules: true });
+      });
+    });
+
     it('replaces the package.json with the backed up version', () => {
       fs.ensureDirSync('packages/test/node_modules');