The trust is currently restoring the castle and wants to create a knot garden on the site of the original mid-17th-century garden.
The competition is open to all amateur garden designers, with prizes awarded in each of the categories for children, students and adults. The overall winner will receive £350 towards a holiday in a Landmark Trust building, and will see their design realised at the castle.
Caroline Stanford, historian at the Landmark Trust, said: ‘Knot gardens were at the height of their popularity from the mid 16th to mid 17th centuries, when the one at Astley was created.
‘It’s exciting to create a new 21st-century garden over 300 years after the first one was planted.
‘We want something that’s symbolic and evocative of the site’s history, but also celebrates the new life we’re bringing to the castle.’
Astley Castle has been owned by three queens of England, including Lady Jane Grey. It was damaged in a fire in 1978, and is being restored by the Landmark Trust, who will make it available as a place to stay and also hold regular open days.
To enter the competition, download the entry pack. The closing date for entries is September 24.
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