Wrest Park won £139,000 in late 2008 to develop detailed proposals. A second-round application to secure the full grant of £1.14m has now been awarded.
Part of the HLF development grant will be used to fund an audience development manager to work with individuals and community groups from the surrounding area.
English Heritage head of gardens and landscapes John Watkins said money would go towards better car parking, a relaid kitchen garden and a tied-in apprenticeship.
Meanwhile, a £2.1m recreation of historic gardens at Kenilworth Castle has paid off, with a 50,000 boost in visitor numbers to 140,000, added Watkins. "It won't take that long to pay off and it has made a difference to local businesses," he said.
The project was part of a May 2009 BBC television series that highlighted delays and rising costs. Over the next 20 years at Wrest Park, English Heritage plans to:
- Repair Capability Brown's lakes.
- Restore fountains and reinstate round pond at Atlas statue.
- Refurnish garden "rooms".
- Replant the Italian Garden.
- Develop a garden apprenticeship training scheme.
- Develop visitor facilities.