diff --git a/pkg/tsdb/elasticsearch/response_parser.go b/pkg/tsdb/elasticsearch/response_parser.go
index 9154d43a062..914636f11f2 100644
--- a/pkg/tsdb/elasticsearch/response_parser.go
+++ b/pkg/tsdb/elasticsearch/response_parser.go
@@ -527,7 +527,7 @@ func (rp *responseParser) trimDatapoints(queryResult backend.DataResponse, targe
 		return
 	}
 
-	trimEdges, err := histogram.Settings.Get("trimEdges").Int()
+	trimEdges, err := castToInt(histogram.Settings.Get("trimEdges"))
 	if err != nil {
 		return
 	}
@@ -538,7 +538,7 @@ func (rp *responseParser) trimDatapoints(queryResult backend.DataResponse, targe
 		for _, field := range frame.Fields {
 			if field.Len() > trimEdges*2 {
 				for i := 0; i < field.Len(); i++ {
-					if i < trimEdges || i > field.Len()-trimEdges {
+					if i < trimEdges || i >= field.Len()-trimEdges {
 						field.Delete(i)
 					}
 				}
@@ -674,6 +674,25 @@ func (rp *responseParser) getMetricName(metric string) string {
 	return metric
 }
 
+func castToInt(j *simplejson.Json) (int, error) {
+	i, err := j.Int()
+	if err == nil {
+		return i, nil
+	}
+
+	s, err := j.String()
+	if err != nil {
+		return 0, err
+	}
+
+	v, err := strconv.Atoi(s)
+	if err != nil {
+		return 0, err
+	}
+
+	return v, nil
+}
+
 func castToFloat(j *simplejson.Json) *float64 {
 	f, err := j.Float64()
 	if err == nil {
diff --git a/pkg/tsdb/elasticsearch/response_parser_test.go b/pkg/tsdb/elasticsearch/response_parser_test.go
index 3dfd25da30d..a0ead1663aa 100644
--- a/pkg/tsdb/elasticsearch/response_parser_test.go
+++ b/pkg/tsdb/elasticsearch/response_parser_test.go
@@ -634,7 +634,7 @@ func TestResponseParser(t *testing.T) {
 			assert.Equal(t, frame.Fields[1].Config.DisplayNameFromDS, "@metric:logins.count")
 		})
 
-		t.Run("With dropfirst and last aggregation", func(t *testing.T) {
+		t.Run("With drop first and last aggregation (numeric)", func(t *testing.T) {
 			targets := map[string]string{
 				"A": `{
 					"timeField": "@timestamp",
@@ -691,17 +691,88 @@ func TestResponseParser(t *testing.T) {
 			frame := dataframes[0]
 			require.Len(t, frame.Fields, 2)
 			require.Equal(t, frame.Fields[0].Name, "time")
-			require.Equal(t, frame.Fields[0].Len(), 2)
+			require.Equal(t, frame.Fields[0].Len(), 1)
 			require.Equal(t, frame.Fields[1].Name, "value")
-			require.Equal(t, frame.Fields[1].Len(), 2)
+			require.Equal(t, frame.Fields[1].Len(), 1)
 			assert.Equal(t, frame.Fields[1].Config.DisplayNameFromDS, "Average")
 
 			frame = dataframes[1]
 			require.Len(t, frame.Fields, 2)
 			require.Equal(t, frame.Fields[0].Name, "time")
-			require.Equal(t, frame.Fields[0].Len(), 2)
+			require.Equal(t, frame.Fields[0].Len(), 1)
 			require.Equal(t, frame.Fields[1].Name, "value")
-			require.Equal(t, frame.Fields[1].Len(), 2)
+			require.Equal(t, frame.Fields[1].Len(), 1)
+			assert.Equal(t, frame.Fields[1].Config.DisplayNameFromDS, "Count")
+		})
+
+		t.Run("With drop first and last aggregation (string)", func(t *testing.T) {
+			targets := map[string]string{
+				"A": `{
+					"timeField": "@timestamp",
+					"metrics": [{ "type": "avg", "id": "1" }, { "type": "count" }],
+          "bucketAggs": [
+						{
+							"type": "date_histogram",
+							"field": "@timestamp",
+							"id": "2",
+							"settings": { "trimEdges": "1" }
+						}
+					]
+				}`,
+			}
+			response := `{
+        "responses": [
+          {
+            "aggregations": {
+              "2": {
+                "buckets": [
+                  {
+                    "1": { "value": 1000 },
+                    "key": 1,
+                    "doc_count": 369
+                  },
+                  {
+                    "1": { "value": 2000 },
+                    "key": 2,
+                    "doc_count": 200
+                  },
+                  {
+                    "1": { "value": 2000 },
+                    "key": 3,
+                    "doc_count": 200
+                  }
+                ]
+              }
+            }
+          }
+        ]
+			}`
+			rp, err := newResponseParserForTest(targets, response)
+			require.NoError(t, err)
+			result, err := rp.getTimeSeries()
+			require.NoError(t, err)
+			require.Len(t, result.Responses, 1)
+
+			queryRes := result.Responses["A"]
+			require.NotNil(t, queryRes)
+			dataframes := queryRes.Frames
+			require.NoError(t, err)
+			require.Len(t, dataframes, 2)
+
+			frame := dataframes[0]
+			require.Len(t, frame.Fields, 2)
+			require.Equal(t, frame.Fields[0].Name, "time")
+			require.Equal(t, frame.Fields[0].Len(), 1)
+			require.Equal(t, frame.Fields[1].Name, "value")
+			require.Equal(t, frame.Fields[1].Len(), 1)
+			assert.Equal(t, frame.Fields[1].Config.DisplayNameFromDS, "Average")
+
+			frame = dataframes[1]
+			require.Len(t, frame.Fields, 2)
+			require.Equal(t, frame.Fields[0].Name, "time")
+			require.Equal(t, frame.Fields[0].Len(), 1)
+			require.Equal(t, frame.Fields[1].Name, "value")
+			require.Equal(t, frame.Fields[1].Len(), 1)
 			assert.Equal(t, frame.Fields[1].Config.DisplayNameFromDS, "Count")
 		})