diff --git a/panda/src/particlesystem/baseParticleFactory.cxx b/panda/src/particlesystem/baseParticleFactory.cxx
index 0200aab633..6f78a9f42d 100644
--- a/panda/src/particlesystem/baseParticleFactory.cxx
+++ b/panda/src/particlesystem/baseParticleFactory.cxx
@@ -70,6 +70,7 @@ populate_particle(BaseParticle *bp) {
   bp->set_active(false);
   bp->set_alive(false);
   bp->set_age(0.0f);
+  bp->set_index(0);
 
   populate_child_particle(bp);
 }