I need to book a birthday lunch for DH’s 40th next week. It’s forecast to be 24C so ideally somewhere outside that’s extra special when the weather is good. We’re in Herts but willing to travel. I initially thought of Petersham Nurseries in Richmond but the reviews are consistently underwhelming so not sure anymore, particularly given how expensive it is. Ideally it would be somewhere we can go for a walk afterwards or do something fun. Any ideas please lovely MNers?