diff --git a/src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/CArrayInstance.java b/src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/CArrayInstance.java
index 03392697f6..e5b27d10ec 100644
--- a/src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/CArrayInstance.java
+++ b/src/vm/jvm/runtime/org/perl6/nqp/sixmodel/reprs/CArrayInstance.java
@@ -168,6 +168,7 @@ private void expand(ThreadContext tc, long new_size) {
 
         if (managed) {
             Memory new_storage = new Memory(new_size*repr_data.jna_size);
+            new_storage.clear();
             if (storage != null) {
                 Memory old_storage = (Memory) storage;
                 new_storage.write(0, old_storage.getByteArray(0, (int) old_storage.size()), 0, (int) old_storage.size());