diff --git a/inventory/sample/group_vars/k8s-cluster/k8s-net-calico.yml b/inventory/sample/group_vars/k8s-cluster/k8s-net-calico.yml
index 1c938de199fd3868ee0de8032dc4e393ea9d7fe4..a7c78f6e52cb7652a3d35fd547363afc1097dae4 100644
--- a/inventory/sample/group_vars/k8s-cluster/k8s-net-calico.yml
+++ b/inventory/sample/group_vars/k8s-cluster/k8s-net-calico.yml
@@ -11,6 +11,9 @@
 # add default ippool name
 # calico_pool_name: "default-pool"
 
+# add default ippool blockSize (defaults kube_network_node_prefix)
+# calico_pool_blocksize: 24
+
 # add default ippool CIDR (must be inside kube_pods_subnet, defaults to kube_pods_subnet otherwise)
 # calico_pool_cidr: 1.2.3.4/5
 
diff --git a/roles/network_plugin/calico/tasks/install.yml b/roles/network_plugin/calico/tasks/install.yml
index 7a920e41d8bbe60e1b338738098ba37411dbc428..bd54e02014d519f09bf4add6780494e019f3b451 100644
--- a/roles/network_plugin/calico/tasks/install.yml
+++ b/roles/network_plugin/calico/tasks/install.yml
@@ -128,7 +128,7 @@
           "name": "{{ calico_pool_name }}",
         },
         "spec": {
-          "blockSize": "{{ kube_network_node_prefix }}",
+          "blockSize": "{{ calico_pool_blocksize | default(kube_network_node_prefix) }}",
           "cidr": "{{ calico_pool_cidr | default(kube_pods_subnet) }}",
           "ipipMode": "{{ ipip_mode }}",
           "natOutgoing": {{ nat_outgoing|default(false) and not peer_with_router|default(false) }} }} " | {{ bin_dir }}/calicoctl.sh apply -f -