A 300-acre arable farm in the heart of Norfolk has been turned into an wildlife oasis in the past 15 years.

While many fields are growing crops of wheat and barley, the southern block of the farm near Hingham has been transformed into flower-rich meadows and areas planted specifically to attract birds.

The centre of the farm, which includes the spring-fed 20-acre mere, woodland and adjoining turf meadows, has been transformed into a rich habitat for birds, bees and other wildlife by Michael and Judy Watson.

They took on Sea Mere in 1996 – the inland site takes its name from an expanse of water thought to have been a geological relic, possibly as a result of glaciation and melting after the last ice age. The water level has always remained fairly constant, because it is fed by springs and it feeds a stream that runs into the River Yare.

It is thought that the mere may have been 25m deep. 'Now it is about 5m deep, with steeply-sloping sides. One theory is that it was formed as a kettlehole by a melting glacier, hence the round shape,' said Mrs Watson.

She runs a study centre in converted stables offering the Royal Horticultural Society's Level 2 certificates in the principles of horticulture, encourages visits from organised school parties and runs more advanced horticultural courses when required.

Also, the farm has hosted bank holiday camping weekends for the Countrysiders, the junior arm of Norfolk young farmers.

Diversifying into educational access has enabled children at foundation stage and key stages one and two to learn more about flora and fauna during their typical two-hour visits.

Mr and Mrs Watson applied to enter the higher-level environmental stewardship scheme, which also funds free visits for school educational visits, alongside the existing 36- hectare or 90-acre SSSI (site of special scientific interest).

With a total of 40 acres of woodland, plus 20 acres of water, it made practical sense to take land out of production.

'Some was simply too wet and boggy, and other areas were too marginal,' said Mrs Watson, who has also transformed the mainly south-facing areas into extensive gardens.

A strict regime of managed hedge trimming into 'A' shapes has been implemented. The hedges are cut by staff from Hardingham Farms in rotation to ensure good, healthy regrowth. The mere, marshes and grazing meadows provide nesting habitats for breeding birds including the kingfisher, great-crested grebe and snipe.

An area of wild flower meadows planted with a perennial mix in 2008 had improved year by year, said Mrs Watson.

'This will be their third year of proper flowering. The mass of cowslips has given way to large patches of red clover, oxeye daisies, yarrow and birdsfoot trefoil: and knapweeds, scabious, selfheal and lady's bedstraw add to the tapestry of colour,' she added.

As part of the higher-level scheme, hundreds of metres of new hedges have been planted and one field of about 10 acres has been divided into two, enabling a once-isolated oak tree to be incorporated again into the line of the original field boundary.

Nearby, another three-acre field has been turned into a field-scale bird table, with half planted every other year with a wild bird food mix.

'Our largest field on the farm is 14 acres and the smallest five acres,' said Mrs Watson.

With such a rich blend of wildlife and conservation features and with just 80 acres of arable, the decision to 'farm the environ- ment' has been entirely logical.

'We were a little uneasy at first when we took land out of production, but maybe in 20, 30 or even 40 years it might change again,' said Mr Watson.

Sea Mere gardens and wild flower meadows will be open in aid of the Yare Valley & District Citizens Advice Bureau on Sunday, May 29 and Monday, May 30, 1pm - 5pm; �4 entry, children under 12 free, no dogs; teas and plant stall. Visitors will be welcomed to join guided walks with Martin Hosier, who counts the birds every month, and Rory Hart. Sea Mere is one mile east of Hingham and is signposted from the B1108 Norwich to Watton road. More information at www.seamere.com

michael.pollitt@archant.co.uk