Get order shipment information

Orders in Magento doesn't have a shipping date. They have shipments, and each one of them have a creation date.

You can access an order shipments using

$order->getShipmentsCollection();

Then on a shipment you can call getCreatedAt() to retreive creation date.

Thus, the full code will be

/** @var $order Mage_Sales_Model_Order */
foreach($order->getShipmentsCollection() as $shipment){
    /** @var $shipment Mage_Sales_Model_Order_Shipment */
    echo $shipment->getCreatedAt();
}