A garden is known to have existed in the 16th century. Further planting took place in the mid 18th century. By the early 19th century the designed landscape had been laid out and by 1830 the Terrace Garden had been planted.
The island of Megginch was probably an early Christian monastery but the oldest surviving building on the estate is the Ceinn Torr Tower and fortalice, mentioned in a document of 1460 as 'the tower and fortalice of Megginch.' In 1575 a wing was added to it by the Hay family. The first planting is attributed to the monks who are reputed to have planted a yew hedge, now the four enormous yews marking the outside edges of the Terrace Garden today, and thought to be about 1000 years old. The tallest one is 72', the highest yew tree in Scotland. In 1664 John Drummond bought the property and it still belongs to his descendants. During the Uprisings in the early 18th century, the Drummonds supported the government.
In the 1760s, Colin Drummond and his wife emigrated to Canada and the lime avenue is said to have been planted by his wife before she went. By the end of the century, Colin's son, Robert Drummond, was a Captain of an East Indiaman ship and traded with the Far East. This brought prosperity to the family and soon he began to improve his estate. He asked Robert Adam to extend the house and redecorate some of the main rooms. Captain Drummond built the Stables, several Lodges and Follies, extended the Kitchen Garden and started planting the park.
His brother Adam entered the Navy and rose to the rank of Admiral. He married Lady Charlotte Murray, the eldest daughter of the 4th Duke of Atholl. The 4th Duke was a renowned forester and carried out extensive planting at Blair Atholl. He might have influenced his son-in-law, Adam Drummond, who planted many trees and probably laid out the policies at Megginch.
For a large part of the 19th century, Adam's son, John Murray Drummond, cared for Megginch. In 1889, John Drummond's son, Malcolm, inherited. He had married the Hon Geraldine Tyssen-Amherst, who was the sister of Alicia Tyssen-Amherst, a renowned garden historian and author of 'The History of Gardening'. Alicia frequently stayed at Megginch and many of her photographs provide interesting records of the gardens. Lady Charlotte and Geraldine laid out the parterres in the Terrace Garden in about 1830 and naturalized many wild flowers by scattering seeds throughout the woodlands. In 1924, Geraldine's son, John, succeeded and later, on the death of the 9th Duke of Atholl, inherited the title of Baron Strange. His daughter, now Lady Strange, and her husband live at Megginch and manage the estate.
Megginch Castle, listed category A, was built around a 15th century tower and fortalice. It was added to in 1575, and again between 1707 and 1715. Further decorations were designed by Robert Adam in 1790. In 1820 the alterations were completed by W.M. Mackenzie. In 1928 Mills and Shepherd altered the Castle and added an entrance porch. After a substantial fire the Mills and Shepherd alterations were removed and in 1970 the area restored to the early 19th century period. The Castle is basically L-shaped with three storeys and a tower. Just to the north-west lie the Screen Walls and Outbuildings which are listed with the Castle. The Stables and Doocot, listed category B, were built in 1806 by Robert Drummond. The octagonal doocot, designed like a pagoda, has a model of Robert Drummond's ship, the 'General Elliot', on top acting as a weather vane. In 1815, an oak tree was planted in the centre of the courtyard to commemorate Robert Drummond.
The Walled Garden, listed category B, is in two parts. The northern section was built in 1807 by Robert Drummond. The southern wall has a sundial attached to it, dated about 1575. To the west of the Walled Garden lies the Icehouse, listed category B, which was built in the late 18th century. The Kennels, listed category C, were built in 1930 in a gothic style with diamond shaped windows.
The Chapel, listed category B, was burnt by John Knox. It was rebuilt in 1679 and was rebuilt again in 1781. A late 17th century type of sundial, with an inscription dated 1890 on it, stands next to the small burial ground adjoining the chapel. The gothic North Lodge and Screen, listed category B, were built in 1796 by Robert Drummond. The West Lodge at the end of My Lady's Walk is listed category B and was also built by Robert Drummond in about 1806. The 'ruined' Gothic Arch at the entrance to the Beech Walk is listed category C(S) and was built around 1800 by Robert Drummond. The Mains, a brick farmhouse of 1740, was added to by Frances Drummond, widow of John Murray Drummond in 1891. The Kingdom Farm Buildings were built by John Drummond about 1750. The derelict South Lodge stands near Errol Station.
The 10 large oak trees in the parkland south of the Castle were planted by John Drummond in 1709. Thomas Hunter, in his description of Megginch published in 1883, records oaks, elms, limes, sweet chestnuts and larches growing in the park. The larches were introduced from Blair Atholl.
The northern section is divided by two great avenues; the one leading from the gothic arch to the A85 is called Long Walk and was planted with oaks by Admiral Sir Adam Drummond in 1827 to replace an earlier avenue called the Great Avenue. From the Gothic Arch east to the drive is the Beech Walk, planted about 1750 by Adam Drummond. The other is the oak avenue leading to the North Lodge and main entrance gates planted in 1726 by John Drummond. The lime avenue planted by Mrs Colin Drummond before 1760 runs due west from the Stableyard and could have joined the other main avenue taken out by 1806. Before Mrs. Drummond went to Canada in 1760 she was able to join her handkerchief round the trunk of one of these trees. A third, and not so significant avenue, runs along the east drive and was planted with hardwoods, mainly oak, sycamore, sweet chestnut, lime and beech in around 1840, probably replacing the avenue shown on General Roy's plan. The 1st edition OS plan shows several specimen trees dotted about the park but very few remain today and most of the fields are cultivated with arable crops.
The narrow shelterbelt of trees enclosing the inner park was probably planted about 1790 with beech, oak, elm and some larch. Some were replanted in the 1880s and a small plantation of conifers has been recently added in the south- east corner. The southern area of the park has now been fenced off for a new planting of hardwoods. Pannoch Wood and North Belting Wood, planted in 1796, were partially replanted with mixed hardwoods and some Scots pine and larch in the 1880s probably after the ferocious storm in 1881. Another lime avenue was also planted. Several trees of the original planting in 1796 were left and are still growing among the later trees today. A few ornamental trees, particularly conifers, were also planted in the woodland.
The Terrace Garden lies to the west of the castle, and the Rose Garden lies to the north adjacent to the Walled Garden. The four clumps of extremely old yews mark the outside edge of the Terrace Garden which according to legend were the yew hedge round the monastery garden, and were described as 'very old' in 1702. Lady Charlotte Drummond laid out the garden about 1830 and planted the holly varieties of 'Golden King', 'Silver Queen' and Grandis. (These have been identified by Susyn Andrews of the Royal Botanic Gardens, Kew who had not previously seen these varieties in gardens planted before 1863 or 1867.) The extravagant topiary yew figures were set out by Mrs Malcolm Drummond in the 1890s. An enormous crown, made from gold and green yew, was planted to commemorate Queen Victoria's Golden Jubilee in 1887 (and the Golden Wedding of John and Frances Drummond in 1885). The parterres are still planted with tulips and forget-me-nots in spring, and colourful annuals in summer. On the north side, shrubs and herbaceous perennials are planted along the walks and hedges. They include the rare white form of Rosa banksiana, said to have been grown from seed brought back from India in 1796 in the 'General Elliott'. Two years before, the double red camellia was sent from China to Megginch; it still occasionally flowers.
North of the Castle is the Rose Garden, laid out with box hedges and brick paving, and containing over 100 different varieties of shrub roses, some of the earliest ones were imported from Holland in 1702. Many more were planted by Lady Charlotte in the 1830s, some by Geraldine in the 1890s, and others by Violet in the 1930s, and many more since 1966.
The top walled kitchen garden is known to have been here since 1575, which is the date of the sundial on the wall, though the brick walls are almost certainly 1715 and built onto older stone foundations. It has an early Wisteria brought from China in the 1790s, and the garden has been partly restored as a Herb and Physic garden. There are also plans for an astrological garden.
The Kitchen Garden was extended in 1796 and the 'hot walls' were constructed at the same time. They were made with flues from coal burning stoves which ran through the wall, heating the special brick facings on the walls to prevent late frosts from damaging flowering or budding fruit. Peaches, nectarines and apricots are still grown on this wall. On the north wall are some red currants which have been growing there since 1783. Apples, pears, plums, cherries and greengages are all trained along the walls. The earliest recorded is of the cherry, Governor Wood, planted in 1880. Vegetables are still grown to supply the Castle, and red currants and blackcurrants are grown for sale. There are two long flower borders bedded out each year down the centre, and a good crop of hay is taken off the rest for the wild White Park Cattle.
To the north of the north wall is a large orchard. Its original extent can be seen in the 1st edition OS plan. Many of the trees are still growing and some are quite old, including varieties like the Drummond Pear, Bishop's Mells, Winter Strawberry, the Bloody Ploughman and Tower of Glamis. There is a planned re-planting of fruit trees every year, mostly Victoria Plums, with some Greengages, ornamental Malus and Rowans. About 2 tons of Victoria Plums are sold from the orchard each year. Two greenhouses were demolished in 1946 and 1954, and were replaced by a modern long one to the north of the garden. Last year a plastic tunnel was installed instead of the old frames, some of which are now planted out with heathers, rosemary, periwinkle, Hypericum and lily of the valley. There are also two sheds used for storage and potting, and a toolshed.