diff --git a/doc/src/sgml/ref/explain.sgml b/doc/src/sgml/ref/explain.sgml
index 1c19e254dc..906b2ccd50 100644
--- a/doc/src/sgml/ref/explain.sgml
+++ b/doc/src/sgml/ref/explain.sgml
@@ -187,8 +187,7 @@ ROLLBACK;
       query processing.
       The number of blocks shown for an
       upper-level node includes those used by all its child nodes.  In text
-      format, only non-zero values are printed.  This parameter may only be
-      used when <literal>ANALYZE</literal> is also enabled.  It defaults to
+      format, only non-zero values are printed.  It defaults to
       <literal>FALSE</literal>.
      </para>
     </listitem>
diff --git a/src/backend/commands/explain.c b/src/backend/commands/explain.c
index 4cb3215728..7289054209 100644
--- a/src/backend/commands/explain.c
+++ b/src/backend/commands/explain.c
@@ -223,10 +223,13 @@ ExplainQuery(ParseState *pstate, ExplainStmt *stmt,
 					 parser_errposition(pstate, opt->location)));
 	}
 
-	if (es->buffers && !es->analyze)
+	/* if the summary was not set explicitly, enable it if buffers are */
+	es->summary = (summary_set) ? es->summary : es->buffers;
+
+	if (es->buffers && !es->analyze && !es->summary)
 		ereport(ERROR,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
-				 errmsg("EXPLAIN option BUFFERS requires ANALYZE")));
+				 errmsg("EXPLAIN option BUFFERS requires ANALYZE or SUMMARY")));
 
 	if (es->wal && !es->analyze)
 		ereport(ERROR,
@@ -242,8 +245,8 @@ ExplainQuery(ParseState *pstate, ExplainStmt *stmt,
 				(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
 				 errmsg("EXPLAIN option TIMING requires ANALYZE")));
 
-	/* if the summary was not set explicitly, set default value */
-	es->summary = (summary_set) ? es->summary : es->analyze;
+	/* if the summary was not set explicitly, enable it if analyze is on. */
+	es->summary |= (summary_set) ? es->summary : es->analyze;
 
 	/*
 	 * Parse analysis was done already, but we still have to run the rule