Glen Usk (nprn 36939) is located to the east of Llanhennock, above the north bank of the river Usk. The gardens lie mainly to the south and south-east of the house on ground that falls away steeply to the river which is visible from the gardens. They comprise two distinct construction phases: a Regency garden layout of the 1820s, when the house was built, within which is set an Arts-and-Crafts garden of the early 1920s. 

In the 1820s the curving drive from the north was built (36940) along with the forecourt, a free-standing classical building west of the house, known as The Temple (23099), a walled garden south of the stable block, and a lawn to the south of the house. The lawn was bounded by a low wall ornamented with urns and a ha-ha, the edge of the present lawn. Also included (from the 1903 Sale Particulars), were an octagonal conservatory/monkey house to the east of the house (now demolished), a tennis court and an orchard. Woodland north of the road was already developed, in a small cwm, with a reservoir and fountain, and an unwalled kitchen garden, now a rough field, at the south-west end of the wood.

Extensive remodelling in the early 1920s extended the gardens to the south and east with a series of terraces linked by stone steps. There are three terraces to the east of the house. At the lower level are two large ones, formerly tennis courts, the west one now a lawn. The east one is backed by a high stone wall with central pavilion and surrounded on the other three sides by a stone pergola.

The formal terraced gardens are flanked by slopes planted with trees and rhododendrons through which are woodland walks. A sunken rectangular area above the hard tennis court was a formal rose garden but is now grassed over, with a massive rockery at its east end. At its east end is a large stone statue of an archer, originally from the park at Llantarnam Abbey and of seventeenth century date. Most planting in the gardens is relatively recent.
The present kitchen garden, to the south of the stable block, was originally a nursery garden, built in the 1820s. It is rectangular, bounded by stone walls but on the north side is flanked by the stable block against which are two lean-to glass-houses. The interior is now grass with a circular pool in the middle. In the south wall an iron gate with a yew arch leads to steps down to the sunken garden. In the field below the gardens ponds have been created.

Sources:
Cadw 1994: Register of Parks and Gardens of Special Historic Interest in Wales: Gwent, 40-2 (ref: PGW (Gt)36(MON)).
RCAHMW air photos: 94-CS 0416-7; 945058/65-6.

RCAHMW, 14 June 2022