Some of the finest gardens in Wales have been immaculately restored and maintained by the National Trust – often with a castle or stately home thrown in for good measure. Here are a dozen jewels of Welsh horticulture.

Chirk Castle, Wrexham

Mature trees and elaborate gates seem to be everywhere at Chirk, originally crafted by local smiths the Davies brothers almost 300 years ago. A formal garden is home to clipped yews, roses and climbers on the wall of the castle. A shrub garden, a classical pavilion and a lime tree avenue also feature.

Plas Newydd, Anglesey

Picturesquely located near the shores of the Menai Strait, Plas Newydd boasts a spring garden, Australasian arboretum, shrubs, wildflowers, massed hydrangeas and explosions of colour. There are terrific views across the water to Snowdonia, and it’s one the UK’s last strongholds of the native red squirrel – the estate has a population of around 100 of these delightful creatures.

Erddig, Wrexham

The large walled garden at the captivating Erddig house and estate has been restored to its original formal design of the 18th century, complete with trained fruit trees. There are also impressive water fetures, a Victorian parterre, yew walk and a National Collection of ivies.

Penrhyn Castle, Bangor

The bog garden and Victorian walled garden are among the highlights in the grounds of the huge neo-Norman Penrhyn Castle. The woodland walks include some superb specimen trees, and views across to the North Wales coastline and mountains beyond.

Colby Woodland Gardens, Pembrokeshire

It’s hard to believe now, but in the 1700s Colby was part of the Pembrokeshire coal belt. Now its informal gardens count rhododendrons, bluebells, butterflies and ducks among its natives. Meadows, a summerhouse and a beach are all nearby, as well as a walled garden and a waterfall walk. It’s a great place for kids, too, with rope swings, stepping stones and geocaching on offer.

Dinefwr Park, Carmarthenshire

The glorious 18th century landscape park at Dinefwr was designed after an inspiring visit by the greatest landscape architect of the day, Capability Brown. It’s part of a wonderful nature reserve within the 800-acre (324ha) estate, where a herd of fallow deer and rare white park cattle roam. A woodland walk leads up from Newton House to the original Dinefwr Castle, power-base of the medieval Deheubarth royal dynasty.

Tredegar House and Park, Newport

Ancient trees, beautiful lakes and three exquisite mansion gardens – orchard, cedar and orangery - surround Tredegar House. This 17th century architectural wonder of Newport has 90 acres (36ha) of grounds and parkland to lose yourself in. The Morgan family – who would become Lords Tredegar – owned this country house for more than 500 years.

Llanerchaeron, Ceredigion

Designed during the 1790s, Llanerchaeron is the most complete early work by John Nash, whose self-sufficient 18th century gentry estate remains almost fully intact for your enjoyment. Pleasure grounds, walled kitchen gardens, a service courtyard and a working organic farm are just a few of the highlights on offer – and the estate’s meat/veg/fruit are available in the shop.

Bodnant Garden, Conwy

A botanical dream, Bodnant houses seeds and cuttings assembled on intrepid expeditions more than a century ago, accompanied by lawns, ponds, terraces, valleys and streams within one incredible 80-acre (32ha) garden. Enormous arch flowers, growing almost 200 feet (60m), are among the spectacular seasonal flourishes here, not to mention the 200-year-old trees – all set against the backdrop of Snowdonia.

Plas yn Rhiw, Llŷn Peninsula

When the Keating sisters bought Plas yn Rhiw in the 1930s, the garden was so besieged by brambles that they had to climb in through a window. They set about creating a magical garden on a hillside overlooking Porth Neigwl (Hells Mouth); the National Trust has continued their work, restoring the gardens, planting hundreds of fruit trees, and extending the estate into woodland.

Powis Castle and Garden, Welshpool

The celebrated 26-acre garden at Powis Castle is a joy to behold. Clipped yews, tender plants and rare specimens are everywhere, laid out in classic French and Italian styles. The terraces are the place to find an orangery, and the castle itself was originally built as a medieval fortress.

Bodysgallen Hall, Llandudno

This grand country manor now runs as a high-end hotel, so access to its magnificent gardens are normally reserved for hotel guests, or those taking afternoon tea. But you can book a tour around the terraces and walled gardens of Bodysgallen Hall with the head gardener, followed by lunch in the 17th century baronial hall.

Dyffryn Gardens, Vale of Glamorgan

The captivating Edwardian gardens at Dyffryn are part of a Grade I-listed landmark dotted with beautiful garden rooms, revolving seasonal displays of wonderful plants and an arboretum with an international cast of trees. You’ve more than 55 acres (22ha) to admire here, as well as an imaginative year-round events programme.