diff --git a/homeassistant/components/gardena_bluetooth/number.py b/homeassistant/components/gardena_bluetooth/number.py
index 41b4f1e79ba..342061c18d1 100644
--- a/homeassistant/components/gardena_bluetooth/number.py
+++ b/homeassistant/components/gardena_bluetooth/number.py
@@ -13,6 +13,7 @@ from gardena_bluetooth.parse import (
 )
 
 from homeassistant.components.number import (
+    NumberDeviceClass,
     NumberEntity,
     NumberEntityDescription,
     NumberMode,
@@ -54,6 +55,7 @@ DESCRIPTIONS = (
         native_step=60,
         entity_category=EntityCategory.CONFIG,
         char=Valve.manual_watering_time,
+        device_class=NumberDeviceClass.DURATION,
     ),
     GardenaBluetoothNumberEntityDescription(
         key=Valve.remaining_open_time.uuid,
@@ -64,6 +66,7 @@ DESCRIPTIONS = (
         native_step=60.0,
         entity_category=EntityCategory.DIAGNOSTIC,
         char=Valve.remaining_open_time,
+        device_class=NumberDeviceClass.DURATION,
     ),
     GardenaBluetoothNumberEntityDescription(
         key=DeviceConfiguration.rain_pause.uuid,
@@ -75,6 +78,7 @@ DESCRIPTIONS = (
         native_step=6 * 60.0,
         entity_category=EntityCategory.CONFIG,
         char=DeviceConfiguration.rain_pause,
+        device_class=NumberDeviceClass.DURATION,
     ),
     GardenaBluetoothNumberEntityDescription(
         key=DeviceConfiguration.seasonal_adjust.uuid,
@@ -86,6 +90,7 @@ DESCRIPTIONS = (
         native_step=1.0,
         entity_category=EntityCategory.CONFIG,
         char=DeviceConfiguration.seasonal_adjust,
+        device_class=NumberDeviceClass.DURATION,
     ),
     GardenaBluetoothNumberEntityDescription(
         key=Sensor.threshold.uuid,
@@ -153,6 +158,7 @@ class GardenaBluetoothRemainingOpenSetNumber(GardenaBluetoothEntity, NumberEntit
     _attr_native_min_value = 0.0
     _attr_native_max_value = 24 * 60
     _attr_native_step = 1.0
+    _attr_device_class = NumberDeviceClass.DURATION
 
     def __init__(
         self,
diff --git a/homeassistant/components/gardena_bluetooth/valve.py b/homeassistant/components/gardena_bluetooth/valve.py
index 4138c7c4472..247a85f93f1 100644
--- a/homeassistant/components/gardena_bluetooth/valve.py
+++ b/homeassistant/components/gardena_bluetooth/valve.py
@@ -6,7 +6,11 @@ from typing import Any
 
 from gardena_bluetooth.const import Valve
 
-from homeassistant.components.valve import ValveEntity, ValveEntityFeature
+from homeassistant.components.valve import (
+    ValveDeviceClass,
+    ValveEntity,
+    ValveEntityFeature,
+)
 from homeassistant.core import HomeAssistant
 from homeassistant.helpers.entity_platform import AddConfigEntryEntitiesCallback
 
@@ -37,6 +41,7 @@ class GardenaBluetoothValve(GardenaBluetoothEntity, ValveEntity):
     _attr_is_closed: bool | None = None
     _attr_reports_position = False
     _attr_supported_features = ValveEntityFeature.OPEN | ValveEntityFeature.CLOSE
+    _attr_device_class = ValveDeviceClass.WATER
 
     characteristics = {
         Valve.state.uuid,
diff --git a/tests/components/gardena_bluetooth/snapshots/test_number.ambr b/tests/components/gardena_bluetooth/snapshots/test_number.ambr
index c89ead450d2..4bc1e7e8dcb 100644
--- a/tests/components/gardena_bluetooth/snapshots/test_number.ambr
+++ b/tests/components/gardena_bluetooth/snapshots/test_number.ambr
@@ -2,6 +2,7 @@
 # name: test_bluetooth_error_unavailable
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Remaining open time',
       'max': 86400,
       'min': 0.0,
@@ -20,6 +21,7 @@
 # name: test_bluetooth_error_unavailable.1
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Manual watering time',
       'max': 86400,
       'min': 0.0,
@@ -38,6 +40,7 @@
 # name: test_bluetooth_error_unavailable.2
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Remaining open time',
       'max': 86400,
       'min': 0.0,
@@ -56,6 +59,7 @@
 # name: test_bluetooth_error_unavailable.3
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Manual watering time',
       'max': 86400,
       'min': 0.0,
@@ -110,6 +114,7 @@
 # name: test_setup[98bd0f13-0b0e-421a-84e5-ddbf75dc6de4-raw1-number.mock_title_remaining_open_time]
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Remaining open time',
       'max': 86400,
       'min': 0.0,
@@ -128,6 +133,7 @@
 # name: test_setup[98bd0f13-0b0e-421a-84e5-ddbf75dc6de4-raw1-number.mock_title_remaining_open_time].1
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Remaining open time',
       'max': 86400,
       'min': 0.0,
@@ -146,6 +152,7 @@
 # name: test_setup[98bd0f13-0b0e-421a-84e5-ddbf75dc6de4-raw1-number.mock_title_remaining_open_time].2
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Remaining open time',
       'max': 86400,
       'min': 0.0,
@@ -164,6 +171,7 @@
 # name: test_setup[98bd0f13-0b0e-421a-84e5-ddbf75dc6de4-raw1-number.mock_title_remaining_open_time].3
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Remaining open time',
       'max': 86400,
       'min': 0.0,
@@ -182,6 +190,7 @@
 # name: test_setup[98bd0f13-0b0e-421a-84e5-ddbf75dc6de4-raw2-number.mock_title_open_for]
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Open for',
       'max': 1440,
       'min': 0.0,
@@ -200,6 +209,7 @@
 # name: test_setup[98bd0f14-0b0e-421a-84e5-ddbf75dc6de4-raw0-number.mock_title_manual_watering_time]
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Manual watering time',
       'max': 86400,
       'min': 0.0,
@@ -218,6 +228,7 @@
 # name: test_setup[98bd0f14-0b0e-421a-84e5-ddbf75dc6de4-raw0-number.mock_title_manual_watering_time].1
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'duration',
       'friendly_name': 'Mock Title Manual watering time',
       'max': 86400,
       'min': 0.0,
diff --git a/tests/components/gardena_bluetooth/snapshots/test_valve.ambr b/tests/components/gardena_bluetooth/snapshots/test_valve.ambr
index c030332e75b..4a0da40a143 100644
--- a/tests/components/gardena_bluetooth/snapshots/test_valve.ambr
+++ b/tests/components/gardena_bluetooth/snapshots/test_valve.ambr
@@ -2,6 +2,7 @@
 # name: test_setup
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'water',
       'friendly_name': 'Mock Title',
       'supported_features': <ValveEntityFeature: 3>,
     }),
@@ -16,6 +17,7 @@
 # name: test_setup.1
   StateSnapshot({
     'attributes': ReadOnlyDict({
+      'device_class': 'water',
       'friendly_name': 'Mock Title',
       'supported_features': <ValveEntityFeature: 3>,
     }),