diff --git a/git-submodule.sh b/git-submodule.sh
index 9bc5c5f94d..2dd29b3df0 100755
--- a/git-submodule.sh
+++ b/git-submodule.sh
@@ -347,7 +347,7 @@ Use -f if you really want to add it." >&2
 				echo "$(eval_gettext "Reactivating local git directory for submodule '\$sm_name'.")"
 			fi
 		fi
-		git submodule--helper clone ${GIT_QUIET:+--quiet} --prefix "$wt_prefix" --path "$sm_path" --name "$sm_name" --url "$realrepo" "$reference" "$depth" || exit
+		git submodule--helper clone ${GIT_QUIET:+--quiet} --prefix "$wt_prefix" --path "$sm_path" --name "$sm_name" --url "$realrepo" ${reference:+"$reference"} ${depth:+"$depth"} || exit
 		(
 			clear_local_git_env
 			cd "$sm_path" &&
@@ -709,7 +709,7 @@ Maybe you want to use 'update --init'?")"
 
 		if ! test -d "$sm_path"/.git && ! test -f "$sm_path"/.git
 		then
-			git submodule--helper clone ${GIT_QUIET:+--quiet} --prefix "$prefix" --path "$sm_path" --name "$name" --url "$url" "$reference" "$depth" || exit
+			git submodule--helper clone ${GIT_QUIET:+--quiet} --prefix "$prefix" --path "$sm_path" --name "$name" --url "$url" ${reference:+"$reference"} ${depth:+"$depth"} || exit
 			cloned_modules="$cloned_modules;$name"
 			subsha1=
 		else