diff --git a/pkgs/applications/office/elementary-planner/default.nix b/pkgs/applications/office/elementary-planner/default.nix
index 3cc94e2ff343..2cb3efd8f308 100644
--- a/pkgs/applications/office/elementary-planner/default.nix
+++ b/pkgs/applications/office/elementary-planner/default.nix
@@ -78,6 +78,8 @@ stdenv.mkDerivation rec {
     gappsWrapperArgs+=(
       # The GTK theme is hardcoded.
       --prefix XDG_DATA_DIRS : "${pantheon.elementary-gtk-theme}/share"
+      # The icon theme is hardcoded.
+      --prefix XDG_DATA_DIRS : "$XDG_ICON_DIRS"
     )
   '';