diff --git a/blueprints/addon/files/addon-config/ember-try.js b/blueprints/addon/files/addon-config/ember-try.js
index 885aa9a250..09bba25073 100644
--- a/blueprints/addon/files/addon-config/ember-try.js
+++ b/blueprints/addon/files/addon-config/ember-try.js
@@ -70,6 +70,9 @@ module.exports = async function () {
           }),
         },
         npm: {
+          devDependencies: {
+            'ember-source': '~3.28.0',
+          },
           ember: {
             edition: 'classic',
           },
diff --git a/tests/fixtures/addon/defaults/config/ember-try.js b/tests/fixtures/addon/defaults/config/ember-try.js
index e6ef3ad925..d563ed58d0 100644
--- a/tests/fixtures/addon/defaults/config/ember-try.js
+++ b/tests/fixtures/addon/defaults/config/ember-try.js
@@ -69,6 +69,9 @@ module.exports = async function () {
           }),
         },
         npm: {
+          devDependencies: {
+            'ember-source': '~3.28.0',
+          },
           ember: {
             edition: 'classic',
           },
diff --git a/tests/fixtures/addon/yarn/config/ember-try.js b/tests/fixtures/addon/yarn/config/ember-try.js
index d8bd6f97de..c9d0dd7931 100644
--- a/tests/fixtures/addon/yarn/config/ember-try.js
+++ b/tests/fixtures/addon/yarn/config/ember-try.js
@@ -70,6 +70,9 @@ module.exports = async function () {
           }),
         },
         npm: {
+          devDependencies: {
+            'ember-source': '~3.28.0',
+          },
           ember: {
             edition: 'classic',
           },