<em>Parrotia persica</em>, Persian ironwood: planting, pruning and care

Description and botany

Persian ironwood (Parrotia persica) belongs to the family Hamamelidaceae and is now the only species of genus Parrotia, although several varieties exist. This small tree or large bush is native to mixed forests of northern Iran and the eastern Caucasus, hence the species name “persica“, but it is becoming rare in its natural habitat. It is called “iron tree” or “ironwood” because of the hardness of its wood. Another of its (many) nicknames is “parrot tree” due to the flamboyant colours of its foliage in autumn. This bush can also be found in older works under the name Hamamelis persica.

Iron tree is a large bush or small tree measuring between 5 and 10 m tall in cultivation, but it can reach up to 20 m in its natural range. It has a stout trunk and a very spreading habit, wider than tall (often nearly 10 metres wide). Branches of older specimens droop to the ground. Its root system is extensive and the tree even tends to sucker.

The bark is grey, but it peels with age to reveal yellowish patches, somewhat like that of a plane tree. Young shoots are green-brown with small hairs and buds of very dark purple, themselves slightly pubescent.

Deciduous foliage consists of ovate leaves about 8 cm long, glossy green in spring and summer (reddish at bud burst period) but gradually becomes very colourful in autumn with colours appearing at the same time: green, yellow, orange and crimson to purple. Upper half of the leaf has rounded teeth and veins are prominent, somewhat reminiscent of beech leaf. It is therefore also nicknamed “Persian beech“.

Flowers are hermaphrodite, small and without petals, and consist of scarlet stamens surrounded by brown bracts. They appear directly on the branches at the end of winter (late February–early March) just before the leaves emerge. Although inconspicuous, flowers are very melliferous and provide an excellent food source for early pollinators emerging from winter. Fruit resulting from fertilization somewhat resembles a walnut and consists of a hairy capsule with four compartments. Seeds are light brown.

Parrotia persica : flowering, spring foliage then autumn foliage, beautiful bark

Parrotia reaches sexual maturity at around ten years of age. It is a relatively slow-growing tree, gaining only about 30 cm per year, but it can easily live two hundred years.

please note: only one species remains in genus Parrotia. It formerly included others such as Parrotiopsis jacquemontiana (formerly Parrotia jacquemontiana) and Parrotia subaequalis (now Shaniodendron subaequalis).

Our favourite varieties

Parrotia persica - Persian Ironwood

This is the type species. Parrotia persica is a small deciduous tree that dons magnificent autumn colours, blending green, yellow, orange, red and purple. Its unobtrusive spring flowering is highly melliferous. In winter, it retains a striking presence when it reveals its beautifully peeling bark.

• Flowering time March to May
• Height at maturity 8 m

See the product sheet

Parrotia persica Vanessa - Persian Ironwood

Parrotia persica 'Vanessa' is an older horticultural selection that remains highly prized for its almost columnar habit, considerably narrower than the type species. That makes it particularly valuable in small gardens while retaining typical Parrotia qualities, notably its incredible autumn colours.

• Flowering time March to May
• Height at maturity 6,50 m

See the product sheet

Parrotia persica Persian Spire - Persian Ironwood

Parrotia persica Persian Spire® is a brand new variety with a narrow habit and reduced vigour. Its foliage is remarkably colourful from spring to autumn as it emerges purple at bud burst period, turning in summer to glossy green widely marginate with violet before the autumn blaze of yellow, orange and red. Unobtrusive, it will fit into any garden, even the smallest, or can even be grown in a container.

• Flowering time March to May
• Height at maturity 7 m

See the product sheet

Parrotia persica Bella - Persian Ironwood

Parrotia persica Bella® is a variety of Persian ironwood that differs from the type species mainly by its less spreading habit, making it easier to adopt in a medium-sized garden. Its narrow ovate crown, semi-open and fairly dense, will not exceed 4.50 m to 5 m in width.

• Flowering time March to May
• Height at maturity 10 m

See the product sheet

Sycoparrotia semidecidua Purple Haze

(x) Sycoparrotia semidecidua 'Purple Haze' is a hybrid between Parrotia persica and Sycopsis sinensis. It is a large bush reaching 3 to 4 m in height with a 4 to 6 m spread, whose foliage and habit show characteristics intermediate between those of its two parents.

• Flowering time March to May
• Height at maturity 4 m

See the product sheet

Planting Parrotia

Where to plant Parrotia?

Parrotia persica is a very hardy tree, as it withstands frosts down to -25°C. However, they dislike heat and dread drought, although they become fairly resilient once established. Therefore avoid planting them south of the Loire, as the climate there suits them poorly.

This tree prefers rich, deep, acidic soils (autumn colours are then far more beautiful) but tolerates calcareous soil. It also needs soil to remain cool, yet well drained. It can readily cope with clay soils.

Ideal exposure is sunny but not scorching, or semi-shade, sheltered from drying wind.

Allow plenty of space for this tree, which tends to spread widely: at least 10 metres wide at maturity. Unless you choose a variety with a narrower habit such as ‘Vanessa’ or ‘Persian Spire’.

When to plant?

Best time to plant is autumn (November–December). Planting is also possible in early spring if soil is not frozen.

How to plant?

• Dip pot of your new Parrotia into a bucket of water for a few minutes to thoroughly rewet the rootball
• Dig a hole twice as deep and twice as wide as the rootball
• Throw a few handfuls of well-rotted compost into bottom of the hole
• If soil is heavy, add some sand or even a little gravel to improve drainage
• Begin gently freeing the roots
• Place remaining rootball in bottom of hole, spreading roots out well
• Fill hole with excavated soil that has been loosened beforehand
• Firm soil gently around tree with your hands (not with your feet!)
• Apply 10 litres of water at the base to reduce risk of “air pockets” between roots and soil
• Apply mulch to protect young tree from drought or plant a few small groundcover plants at the base (creeping bugle, sweet woodruff, Glechoma, Geranium macrorrhizum, …).

Maintenance, pruning and care

Care

Very little care is required for parrotias. Mulching is highly recommended, especially during the first few years, to keep soil cool and retain moisture in summer.

During drought, check whether your Persian Parrotia is suffering from a lack of water.

Pruning

No pruning is really necessary. If required, you can remove, just before growth resumes (February), fragile, dead or crossing branches to preserve a harmonious and healthy habit.

Possible diseases

This bush or small tree suffers from no diseases and is not attacked by pests.

Propagation

Sowing

Sowing is difficult and slow, seeds take 18 months to germinate with a very low germination rate.

Layering

In reality, tree layers naturally. Layering by couching is an easy operation to carry out in March–April. Bend some flexible healthy shoots down to soil. First split the bark of these shoots over a few centimetres and to a thickness of 2 mm. Bury the layers at the split and secure them with a stainless-steel “U” pin. Keep moist and wait at least two years before separating layer from parent plant. Remove gently once rooted then place in pot.

Propagation by cuttings

In June, propagation by cuttings of semi-ripe shoots under cover can be attempted. Take young shoots and make a sloping heel cut. Remove leaves, keeping only one to reduce evapotranspiration. Substrate must be light; a mix of 50% sowing compost and 50% sand will be perfect. Keep moist, but not waterlogged. Unrooted cuttings do not “drink” and excessive moisture will cause rot. First roots will appear as early as autumn, but better to wait until spring to repot. Wait at least until following autumn, or preferably until following year before planting out in open ground.

Grafting

Parrotie is grafted onto Hammamelis: this is normal, they come from same botanical family. This technique is reserved for specialists only (especially given price of Hammamelis…). If you still want to try, the so-called “cleft” graft is used and carried out in February.

Pairing Parrotia in the garden

Within a copse of colourful autumn foliage

Ask gardeners which season is their favourite and some will answer spring, but many will also say autumn. Autumn in the garden and in nature is indeed a magical season. If you love the warm foliage colours of this season, why not create a copse of bushes renowned for their autumnal colours. Parrotia persica ‘Persian Spire’ occupies little width, which makes it perfect to insert into a copse alongside a Liquidambar styraciflua ‘Gum Ball’, a reduced-growth variety with multicoloured autumn foliage. A Forthergilla major will complete the picture while also adding interest in spring thanks to its charming flowering. If you are looking for another member of the Hamamelidaceae family to accompany Parrotia and Forthergilla, choose, of course, a witch-hazel, such as this friendly Hamamelis vernalis ‘Amethyst’ with scarlet foliage in autumn followed by purplish-pink winter flowering.

An example of a copse combination: Parrotia persica ‘Persian Spire’, Liquidambar styraciflua ‘Gum Ball’ with incredible autumn foliage and Fothergilla major, to which you can add a Hamamelis with superb winter flowering such as ‘Amethyst’

Within an informal “four-season” hedge

Parrotia persica ‘Vanessa’ does not take much width, so it is ideal for an informal hedge of bushes coloured by foliage and flowering. To keep year-round interest, play on spring and summer flowerings, autumnal foliage colour and winter presence through colourful bark or distinctive habit, so Parrotia does not steal the show too often. Amelanchier spicata is perfect in an informal hedge: attractive at flowering and during bud burst period in spring, and its foliage takes lovely autumn tints. For summer, a simple but effective Buddleia davidii ‘Empire Blue’, a superb variety that flowers from July to September in long blue spikes, is ideal. To complete the mix, plant freely any dogwoods with decorative wood and foliage that catch your eye. For example: Cornus alba ‘Aurea’ with golden foliage all season and bright red branches in winter, and Cornus sericea ‘Cardinal’ whose fresh green foliage turns reddish in autumn before giving way to red wood in winter.

An example of a four-season hedge combination: Parrotia persica ‘Vanessa’ with lovely autumn colours, Amelanchier spicata which flowers in spring and also offers attractive autumn foliage, Buddleja davidii ‘Empire Blue’, Cornus alba ‘Aurea’ with golden foliage all season and Cornus sericea ‘Cardinal’ valued for its autumn colours and red stems in winter

Alone at the centre of a short grass meadow

The species Parrotia persica gains some width over time (10 metres!) but it is also a very handsome small tree to grow alone, allowing it to reach full stature. Standing proudly in the middle of an open part of your garden, it will quickly become a focal point that delights the heart in autumn when it is cloaked in gold and flame. It will also provide beneficial shade for many attractive plants. If soil is acidic enough, why not try planting heathers, azaleas or Pieris at its base, which will thrive in the shade of this splendid tree.

→ Discover more ideas for combining Parrotia in our advice sheet !

Did you know?

• Genus name Parrotia derives from its discoverer, German naturalist F.W. Parrot.
• It is a melliferous plant that attracts pollinators at a crucial time of year: late winter and the very beginning of spring.
• Parrotia persica was only introduced to Europe in 1841.
• Its vernacular name, iron tree, comes from its exceptionally hard wood.
• Parrotia wood has been used to make tools for more than 2,000 years.