A genus of two species of deciduous tree, Parrotia occurs naturally in the forests of the Caucasus, northern Iran and eastern China. The two species are Parrotia persica, which has the common name of Persian ironwood, and Parrotia subaequalis with the common name Chinese ironwood. Parrotia belongs in the family Hamamelidaceae, where it is a close relative of the witch hazel genus Hamamelis.
The most common species to be found in gardens and landscapes is P. persica, which was named after the German naturalist Friedrich Parrot and introduced to the UK in around 1860. P. subaequalis was originally discovered in China and named in 1960, although not collected again until 1988, and was not introduced into the commercial trade in the UK until 2000.
Although discovered in such geographically distinct areas, both species of Parrotia have similar forms and growth habit. Parrotia is cultivated for its simple alternate rich-green foliage, which turns an attractive reddish colour in autumn, and for its peeling bark and petalless flowers with bright-red stamens.
Parrotia is usually grown as a specimen tree in a planting scheme where it needs lots of space to show off its true character. The red flowers, which consist of the stamens, are a particularly unusual and striking feature because they are borne in dense clusters along the branches in late winter and early spring.
The flowers are similar to witch hazel flowers, in that they appear at the same time of year and are borne on bare stems, but differ in having four round sepals with no petals and are red instead of yellow. The intense patches of bright-red colour provide welcome interest to a garden in the dull period at the end of winter.
The mature Parrotia tree grows to a height of up to 30m — although this can take 15 years — and can offer an imposing centrepiece in any large landscape. Its initial upright habit eventually gives way to a dome shape as the branches spread sideways.
Several cultivars of P. persica have been selected for garden planting depending on particular variations from the original habit, including ‘Horizontalis’, which is a semi-weeping variety with a wide-spreading horizontal branching pattern, and ‘Vanessa’ Award of Garden Merit (AGM), which has an upright columnar habit.
‘Vanessa’ is the most common variety found in planting schemes because it has a slightly smaller habit than P. persica and therefore can be used in a smaller space.
One of the most visibly attractive features of Parrotia is the foliage, which is an attractive scallop shape. For several weeks in mid autumn, each individual leaf appears to be a different shade of red, purple, orange or yellow, providing a stunning focal point. Parrotia also has distinctive bark, which flakes as the tree reaches maturity, revealing patches of pink, green and yellow.
Parrotia prefers a rich, fertile soil that does not dry out because it is intolerant to drought. While it will do best in a well-drained soil, some varieties can survive in damp conditions near streams and water. The tree is also vulnerable to frost because the early flowers will suffer in a hard winter frost.
It is best grown in a sheltered spot on acid soil in full sun or partial shade. For the best autumn colour, Parrotia is best grown in acid conditions, although it can survive in chalky conditions. ‘Vanessa’ can grow on either acid or alkaline soils.
The tree produces fruit that is a double capsule containing two seeds. The seeds can be planted in containers in a cold frame in autumn, although the plant is slow-growing and will take years to reach a size where it is useful in a planting scheme. Greenwood cuttings can be taken in early summer and semi-ripe cuttings in mid-to-late summer. Vegetatively propagated forms provide the most reliability in autumn colour.
Parrotia is best planted on its own as a specimen tree but it can be underplanted with simple plants such as cyclamen. It is very easily maintained because it is largely free from pests and diseases, and pruning consists of removing crossing branches or those that are growing in an unattractive direction.
What the experts say
Simon Scarth, Chew Valley Trees, Somerset
"We sell quite a lot of them — more than we used to. They’re a nice tree with really good autumn colour that holds on for a long time. They take a long time to lose their leaves and give a vibrant autumn display. They’re not too big with a maximum height of 40ft so are good for medium to large gardens. They’re very hardy and they’re different because they haven’t been planted in huge numbers so it’s not like you see them everywhere. We just sell the normal P. persica, Persian ironwood."
Jonathan Davies, sales consultant, Tendercare, Middlesex
"The autumn foliage of Parrotia is fantastic. I’ve made up a 160-plant hot list for autumn and I chose Parrotia for that because of its amazing autumn colour. We have loads of ‘Vanessa’ — 19 of them, with the 130-litre pot giving a lovely looking tree. We also have troughs and other sizes from 90 litres. Most people would go for the Japanese maple but this is a lovely garden tree."
Lee Oakley, Barcham Trees, Cambridgeshire
"I’d recommend ‘Vanessa’ simply because it doesn’t get as big as the standard P. persica. It makes a good pleached tree and has good autumn colour. You do see a bit more on quotes coming into the nursery now but I don’t think it’s near the top 10 sellers. It’s not too big — ‘Vanessa’ is 7m at maturity and it has interesting bark as it gets older."
Andrew Fisher Tomlin, Fisher Tomlin & Bowyer, Surrey
"I love Parrotia. I have three in my own garden, though I have to prune them every year because they get so big. There are amazing Parrotia in the Isabella Plantation in Richmond Park too. I use them but you have to have space for them to really appreciate them. They don’t flower like the books tell you they do. One of mine used to but they don’t anymore. They’re tough old specimens and I love the twisted shape they have to them. I do use them in designs but only in larger gardens and I make sure my clients understand the sort of size they’re going to get to."
Chris Deakin, DeakinLock Garden & Landscape Design, Suffolk
"Parrotia are beautiful. I tend to use them not really often because getting good specimens is sometimes difficult, but they are best in a lawn setting with their stunning autumn colour. I tend to use them standing alone in the middle of the grass. I fell in love with them because there was a fantastic one in the grounds at Writtle when I was at college. They have the best autumn colour and an interesting shape."
Species and varieties
P. persica is a dense spreading short trunked tree with peeling grey and fawn bark when mature. It has obovate glossy rich-green leaves to 12cm in length that turn red, orange, purple and yellow in autumn. Tiny red flowers are produced in spherical clusters 1cm across in late winter and early spring before the leaves appear. Height: 8m. Spread: 10m.
P. persica ‘Bella’ is a relatively new variety of ironwood and features upright branches that hold widely serrated ovate leaves. These leaves are deep-purple when young and then mature to a rich green colour. The leaves also twist slightly, which adds further interest. Height: 8m. Spread: 6m.
P. persica ‘Horizontalis’ is a semi-weeping variety with wide spreading horizontal branching.
P. persica ‘Jodrell Bank’ has an upright form. Height: 10m. Spread: 4m.
P. persica ‘Kew’s Weeping’ is a tight weeping form. Height: 1.5m. Spread: 4.5m.
P. persica ‘Pendula’ is a very compact and weeping variety. Height: 1.5m. Spread: 3m.
P. persica ‘Select’ has purple-edged leaves when they first appear that later become uniformly green after the first flush.
P. persica ‘Vanessa’ AGM is more upright than P. persica and has a narrow column shape. It is a good choice of tree for a smaller space.
P. subaequalis is a rarer variety that is not so commonly found in garden centres and planting schemes. It has small toothed oval leaves and distinctive peeling bark that is brighter in colour than P. persica.