The PLANTS project: Top 12 plants for birds

Gardening with birds and wildlife in mind is very important. The rewards are great – the life, noise and activity that birds and wildlife bring into a garden are unique. In return, birds are highly useful to gardeners; most plants require animal and/or bird assistance, whether through droppings or forgotten burial. During the last three years, the PLANTS project team has come across various plants that provide birds with food and shelter. Include these plants, and your garden will be filled with songs all year. In this blog, the team pick 12 plants to grow for seeds, berries and habitat.

Hawthorn (Crataegus)

Diane, Volunteer, PLANTS Project West

Whether growing as a hedge or a tree, hawthorns can produce many berries. Crataegus is native to the northern temperate regions of Europe, Asia and North America and comprises 250 species. Many are armed with thorns derived from sharp-tipped branches. The PLANTS project has identified 17 species and 5 cultivar forms within our care. 79 instances of the common hawthorn (Crataegus monogyna) have been found, while unusual forms of hawthorn such as Crataegus orientalis subsp. Orientalis native to Turkey and Iran can be found at Threave Garden. Crataegus succulenta var. succulenta (known as ‘fleshy hawthorn’) is found at Castle Fraser. Now rare in its native North American home, it gets its moniker from its fleshy red fruit loved by birds.

The berries, known as haws, are an important winter food source for both native and migrant birds: blackbirds, fieldfares, redwings, song and mistle thrushes, and waxwings will all devour the haws. Birds are enticed by the edible flesh surrounding each hard seed, but they are unable to digest the seed itself, so they will deposit it by dropping, normally some distance away from the parent plant. This provides the potential for a new plant to germinate and grow.

Cotoneaster (Cotoneaster)

Colin, PLANTS Project Manager

A stalwart in many gardens, cotoneaster offers many of the qualities a gardener looks for in a plant: they can cope with most temperatures and, for no effort, reliably produce more than one season of interest – flowers in May and often evergreen leaves and berries in autumn. The species is also wildlife-friendly, offering shelter and food for birds. Its name derives from the Old Latin cotone, meaning ‘quince’, and aster, a Latin substantival suffix indicating ‘resembling’. With over 400 individual species, they vary from creeping groundcover shrubs to small trees.

Cotoneaster horizontalis is the most common species within the Trust, whose low-growing prostrate habit makes for valuable ground cover. The mountain cotoneaster or ‘Giant Snowberry‘, Cotoneaster frigidus, is the best large shrub or tree species of the genus. Native to the Himalayas, frigidus is a firm favourite within Trust gardens and produces large bunches of red berries in autumn while its leaves turn ochre and fall. At Inverewe Garden, we inspected several mature specimens, such as a C. frigidus dating from 1955 on the drive and a C. frigidus var. ‘Cornubia’ from 1956 in the walled garden. These steadfast shrubs are too easy to dismiss, but there is no doubt that birds love the feast and shelter they provide.

Spindle tree (Euonymus sp.)

Niki, PLANTS North Inventory Officer

Some Euonymus species produce beautiful autumnal fruits in the form of their seed capsules: deeply lobed, bulging carpels fused together. Upon ripening, the locule (the outer casing of the capsule) splits and reveals a seed covered in a fleshy coating called an aril. In Euonymus europaeus, these arils are bright orange, in vibrant contrast to the often intense pink outer capsule casings.

The arils and seeds of the Euonymus must surely draw the birds’ attention to the colourful bounty of fats and sugars they contain. Robins, blackbirds and blackcaps enjoy this feast and duly disperse the trees’ seed.

While our avian friends get great edible enjoyment from Euonymus, our pleasure can be visual only, as the fruits of this tree are poisonous to humans! You can explore these captivating fruits in autumn on the champion trees at Crathes Castle in the walled garden, home to several species of Euonymus.

Common holly (Ilex aquifolium)

Lucrezia, PLANTS West Inventory Officer

The Ilex genus, commonly known as holly, belongs to the family Aquifoliaceae and includes over 400 species of trees and shrubs. Found in temperate and tropical regions worldwide, Ilex plants are most recognised for their deep green, spiny, leathery, glossy leaves and vibrant red or orange berries that persist through winter.

Only one species of Ilex is native to the UK, namely Ilex aquifolium. This resilient plant can grow up to 20 metres tall and is often found in oak woodlands or at the margins of forests and clear-cuts. One notable feature of the species is that it is dioecious, meaning it has separate male and female plants. Only the female plants bear the iconic red berries, but they require pollination from nearby males to do so.

Beyond its popularity as an ornamental shrub, particularly Christmas-related, holly is crucial in supporting wildlife. Indeed, its berries are a vital winter food source for birds like redwings, fieldfares, blackbirds and thrushes. One bird species, the mistle thrush, has gained attention for being extremely protective of their holly berries and vigorously guarding them to prevent other birds from eating them!

While this plant is featured in most of our gardens, Drum Castle stands out for its collection of hollies. Over the years, many have been planted here as homage to the rich history of this estate.

Privet hedge (Ligustrum ovalifolium)

Jennifer, PLANTS West Inventory Manager

Although not as fashionable as they once were, privet hedges are common in gardens across the country. The most common privet species, Ligustrum ovalifolium, is not native to the UK but originates in Japan and South Korea. The hedge’s dense structure, made up of small twiggy branches, is an ideal protective habitat for house sparrows and other small birds, more accessible than hedges that are too tightly clipped [1]. House sparrows are gregarious birds that nest in colonies and feed in flocks, often near buildings and cultivated land. They are particularly noticeable in privet hedges in spring when you hear constant chirping from flocks as they socialise and feed during the nesting season.

Six species of Ligustrum have been identified during the project, including the unusual Ligustrum quihoui (or ‘waxy leaf’) privet native to Korea and found in the woodland garden of Balmacara Estate . Noted gardener Christoper Lloyd enjoyed the late-flowering large branched white flower clusters, which make this species particularly valuable. The only example of Ligustrum delavayanum or delavay privet in our gardens is a lovely hedge in front of the Hill House, whose blackberries delight birds in winter.

Apple (Malus sp.)

Lesley, Volunteer, PLANTS Project West

Those with an apple tree know that 2024 has been a good year, with the mild spring weather resulting in bumper crops. Apples can support a broad mix of wildlife, including insects in spring, as the blossom is an early source of pollen and nectar, especially for bees. Windfall apples will attract blackbirds, visiting redwings and ring-necked parakeets, which are also partial to hawthorn berries. The oldest original plant at Greenbank Garden – a ‘Newton Wonder’ apple tree – is home to a family of parakeets. Apple trees provide an excellent food source for birds throughout the year, offering fruit, shelter and nesting sites, making them invaluable to local bird populations.

Bird cherry (Prunus padus)

Alistair, PLANTS North Inventory Manager

Prunus padus is commonly known as bird cherry. Prunus is the Latinised form of the Greek word meaning plum, and padus is the Greek word for a wild cherry. The PLANTS East team came across this species at their first audit of Inveresk Lodge Garden.

Prunus padus is widespread across temperate areas of the northern hemisphere. So far, 23 bird cherry trees have been found across Trust properties and two cultivar forms – ‘Purple Queen’ at Threave Garden and ‘Watereri’ at Crathes Castle. The flowers provide nectar for numerous pollinators, and the ripe cherries are consumed by birds such as robins, starlings, blackbirds, thrushes and warblers, who play a vital role in the dispersal of seeds. These benefit from the very acidic environment in the bird’s gut, which breaks down the hard seed coat and enables germination. The process provides some of the earliest fruits of summer. The black cherries are harsh and bitter to human taste and contain hydrogen cyanide, making them toxic to livestock, particularly goats, but birds tolerate them. Prunus padus provides attractive spring flowers, summer fruits and autumn leaf colour in the landscape.

Oak tree (Quercus spp.)

Charlotte, PLANTS East Inventory Officer

Jays play a crucial part in the lifecycle of the majestic oak, encouraging seed dispersal and natural woodland regeneration. Oak trees support the greatest diversity of life of any tree species in Scotland. A vital space for species to eat, shelter and breed; a haven for lichens, ferns, insects and birds. The Eurasian jay (Garrulus glandarius) is a colourful bird that is part of Scotland’s corvid family. These birds breed in various woodlands but prefer areas with acorns, the fruit of the oak tree.

Sessile oak (Quercus petrea) and pedunculate oak (Quercus robur) are widespread throughout Scotland and in gardens across the Trust. Nearly 500 Quercus robur trees have been recorded as part of the PLANTS project, including a specimen at Greenbank Garden believed to date to 1776. At Hill of Tarvit, the East team came across the unusual bush oak Quercus × bushii ‘Seattle Trident’. In autumn, jays cache the acorns of oak trees for winter food. While these acorns are an important food source for jays, many are forgotten and develop into seedlings come spring. Jays have a tasty meal and support an entire miniature ecosystem.

Rose (Rosa xanthina ‘Canary Bird’)

Colin, PLANTS Project Manager

Some birds love tall shrubs or climbing roses. They offer nesting protection, and the fruits (hips) produced by some varieties after flowering are a rich source of vitamins and antioxidants for overwintering birds.

Rosa xanthina ‘Canary Bird’ is an unusual rose found at Falkland Palace, Branklyn Garden and Brodick Castle. It is one of the earliest roses to flower, usually in late April and early May. The musk-scented, single flowers are held aloft on long, arching, dark red stems. ‘Canary Bird’ is a cultivated form of the Manchu rose, Rosa xanthina, a wild shrub rose native to central China, where it grows in scrubby areas and on open hillsides. As such, ‘Canary Bird’ is hardy and can cope with dry soils. It is easy to prune and can be cut into an informal hedge where its thorniness can protect birds. Meanwhile, its early-blooming, single, yellow flowers are very popular with insects, including hoverflies and bees. Often used in municipal plantings, it is a hedge at the Norwich City (‘Canaries’) football ground, which makes a handsome specimen shrub.

Giant sequoia (Sequoiadendron giganteum)

Claire, PLANTS Data Manager

The massive spires of giant sequoia (Sequoiadendron giganteum) are a familiar sight across parks and gardens in the UK. The PLANTS project team have recorded 84 giant sequoias at 17 Trust properties so far, including an impressive line of specimens at the front of House of Dun. In their native habitat of the western Sierra Nevada in California, their thick spongy bark allows them to withstand regular forest fires. In turn, these fires allow young giant sequoias to establish by clearing competition.

If you take a close look at the trunk of a giant sequoia, you might notice distinctive egg-shaped hollows scraped into the soft bark. These are the roost sites of Eurasian treecreepers (Certhia familiaris), which benefit from the insulating properties of the bark on cold nights. This behaviour has been observed since 1905, only around 50 years since giant sequoias were first introduced to the UK, making this a fascinating example of a native species adapting its behaviour in response to opportunities provided by a tree it would not have encountered in its native range.

Wild teasel (Dipsacus fullonum)

Fran, PLANTS West Inventory Officer

The spiny, cone-shaped teasel seed heads are held on tall stems and are a beautiful addition to the autumn and winter landscape. Their architectural interest in the garden is a good reason for not cutting them back until spring. More importantly, teasels provide a valuable winter food source for birds whose beaks can access the small seeds, most notably goldfinches (collectively known as a ‘charm’). In summer, the tiny lilac-coloured flowers are visited by bees and butterflies. In addition to their wildlife value, dried teasel seed heads were traditionally used in cloth production (for raising the nap). However, a species with curved spine tips was preferred (Dipsacus sativus – fuller’s teasel).

Mistletoe (Viscum album)

Valeria, PLANTS North Inventory Officer

The European mistletoe (Viscum album) is an evergreen, semi-parasitic plant that grows on the branches of trees, such as limes, apples and poplars, extracting water and nutrients from them. Its white berries typically appear from October to May. Mistletoe depends on birds for seed dispersal, particularly the mistle thrush (Turdus viscivorus). The two species share a mutualistic relationship: the mistletoe relies on the mistle thrush to spread its seeds, while the bird benefits from the mistletoe’s berries as a source of food and water. The mistle thrush’s scientific name, Turdus viscivorus, translates to ‘devourer of mistletoe’. The mistletoe’s berries are very sticky, and when eaten by the mistle thrush, they pass through its digestive system, still sticky, allowing the seeds to attach to new host trees. Without the mistle thrush, mistletoes would only spread over a limited area.

Plant Listing at the National Trust for Scotland (PLANTS) is the biggest horticultural audit project undertaken by the Trust and aims to celebrate, protect and better understand the flora and vegetation across our gardens and designed landscapes.

Read more about the PLANTS project

Sources

[1] Glasgow House Sparrow Project