When it comes to maintaining the perfect garden even Monty Don would be proud of, there are a lot of rules to follow. One person that knows these rules better than most is Mike Gogerty, head gardener at Birtsmorton Court, a Grade I listed fortified medieval moated manor house near Malvern in Worcestershire. A gardener with a Royal Horticultural Society qualification, Mr Gogerty is gearing up for the National Garden Scheme, where visitors can gain a rare insight into the gardens of Birtsmorton Court. Ahead of the event, the head gardener has shared his top nine gardening tips to act upon now – including the one sweet pea mistake even the most green fingered gardeners make.