Staphylea - Bladdernut: Planting and Cultivation

Botany and description

The genus Staphylea comprises around ten species of trees, bushes or shrubs found in the damp undergrowth of the northern hemisphere. Staphyleas belong to the Staphyleaceae family.

Among these species are Staphylea x elegans, Staphylea holocarpa, Staphylea bumalda, Staphylea bolanderi, but the three best-known and most widely cultivated species are: Staphylea pinnata (native to Central Europe as far as Alsace and the Jura), Staphylea trifolia (native to the eastern United States) and Staphylea colchica (native to the Caucasus).

Staphylea colchica botanical plate

The genus name “Staphylea” comes from the Greek “staphyl” meaning “bunch of grapes”, referring to the cluster-like shape of the inflorescences. Staphyleas are characterised by opposite, compound leaves with 3 to 7 leaflets, as well as white or pink paniculate flowering and original, persistent fruiting throughout winter.

Staphyleas generally have a slender, well-branched silhouette reaching 3 to 4 m in height (slightly more for Staphylea trifolia). Growth is rapid. The bark is initially smooth, grey-green in colour, lightly striated with white and dotted with lenticels, then over time it cracks and ages beautifully. Staphylea also benefits from being pruned to maintain transparency, allowing part of the bark to be revealed.

The foliage is deciduous, glossy green then yellow in autumn before falling. The leaves are opposite and divided into 3 leaflets in Staphylea trifolia (Three-leaf Bladdernut) or 5 leaflets in Staphylea colchica (Colchis Bladdernut) and Staphylea pinnata (European Bladdernut). Each ovate, acuminate leaflet is delicately and finely dentate. The compound leaf is attached by a petiole surrounded by small bracts. Some cultivars feature very dark foliage, almost black like Staphylea colchica ‘Black Beauty’ or changing like Staphylea colchica ‘Black Jack’ whose foliage turns from green to deep red before finishing orange in autumn.

Left, Staphylea trifolia (© gailhampshire), top right Staphylea pinnata and bottom right Staphylea colchica ‘Black Beauty’

Flowering occurs in spring between April and May. This takes the form of clusters (racemes) of small white bell-shaped flowers (like campanulas), hanging from long peduncles. The flowers are nectariferous and melliferous, emitting a fragrance blending coconut, almond and orange blossom. Note that there is a pink-flowered Staphylea: Staphylea holocarpa var. rosea (though good luck finding it commercially!).

Fruiting is unusual in false pistachios. They form vesicular, trigonous capsules tapering to a point. These capsules change from pinkish-beige to greenish, finishing rust-coloured in winter. The fruits ripen between September and October and remain on the shrub for a long time, even after leaf fall. Each capsule contains 1 to 4 edible seeds when roasted, similar to pistachios.

Note: Staphylea pinnata has been protected in Alsace since 1993 where it is considered a native species.

Staphylea colchica, Staphylea holocarpa ‘Rosea’ and fruiting of Staphylea pinnata

Our most beautiful varieties

Staphylea colchica

Staphylea colchica is a fast-growing bush, perfectly hardy, offering a lovely white flowering in spring, delicately scented and prolonged until late autumn with fruits as curious as they are decorative.

• Flowering time May, June
• Height at maturity 3 m

See the product sheet

Staphylea colchica Black Jack

Staphylea colchica 'Black Jack' is a variety of Bladdernut with exceptional ornamental value. Its leaves turn to very dark, almost black red in summer. Its spring flowering in large, deliciously scented pearly white panicles is followed by curious inflated fruits that remain decorative until winter.

• Flowering time May, June
• Height at maturity 3,50 m

See the product sheet

Staphylea colchica Black Beauty

Staphylea colchica 'Black Beauty' is a variety of Bladdernut distinguished by its glossy foliage coloured chocolate-purple, offering a beautiful contrast between the dark hue of its vegetation and its white spring flowering.

• Flowering time May, June
• Height at maturity 3,25 m

See the product sheet

Staphylea pinnata

Staphylea pinnata, also known as Bladdernut due to its seeds traditionally consumed like pistachios, is a small native tree. It is perfectly adapted to our cold climate and heavy, calcareous soil.

• Flowering time June
• Height at maturity 4 m

See the product sheet

Planting Staphylea

Where to Plant?

Staphyleas should be planted in full sun or partial shade.

The soil should be deep, fertile, and remain moist but well-drained. Although they prefer slightly acidic to neutral soils, they can tolerate slightly alkaline soil, particularly in the case of Staphylea pinnata.

Staphyleas thrive in long, hot summers, which help produce a more abundant flowering the following spring.

When to Plant?

Staphyleas can be planted either in spring (March-April) or autumn (October-November). We recommend autumn planting: the bush will have ample time to establish a strong root system in moist soil before the summer droughts of the following year.

Staphylea pinnata in flower

How to Plant?

In the Ground

• Soak the pot in a basin of water for a few minutes to rehydrate the root ball;
• Remove the plant from the pot, check the roots, and gently loosen the root ball to free them;
• Dig a hole twice as deep and wide as the root system of your bush;
• Loosen the soil at the bottom of the hole and add well-rotted manure or dried blood and ground horn;
• If your soil is heavy (clayey and compact), mix gravel with the excavated soil to improve winter drainage;
• Place your bush in the hole, spreading the roots evenly;
• Backfill with the excavated soil (with or without gravel). Do not bury the collar!;
• Firm the soil around the base of the Staphylea with your hands;
• Water thoroughly. The weight of the water will help eliminate air pockets around the roots;
• You can mulch the surface to retain soil moisture or plant low-growing perennials as ground cover.

In a Pot

Staphylea can be grown in pots if you choose a sufficiently large container: at least 50 cm in width and depth. The pot must have drainage holes to allow excess water to escape. Place a layer of gravel or clay pebbles at the bottom to improve drainage. Use a rich substrate: a mix of 50% good garden soil and 50% high-quality universal compost is ideal. Water well after planting and remember to water during dry spells.

Pruning and maintenance

Watering

For the first two years after planting, remember to water at the base during dry spells. After this period, the bush should withstand drought without issue. However, when grown in containers, thorough watering will be needed whenever the surface of the growing medium dries out.

Don’t forget to mulch or plant ground cover around the base of your Staphylea to maintain soil moisture.

Pruning

Pruning is optional: simply remove dead wood, overly thin or poorly positioned branches. Over time, the Staphylea will benefit from thinning to develop a small tree-like form and showcase its attractive bark. Prune in late winter (March) before foliage appears.

If pruning is absolutely necessary to control growth, you may also prune after flowering in June. However, this will sacrifice its attractive fruit display.

Maintenance

In poor soil, you can apply well-rotted compost around the base of the bush before winter or in spring for plants in the ground. For container-grown plants, use a liquid fertiliser for flowering plants monthly from spring through late summer.

Possible diseases and pests

No need to worry with the False Pistachio. These bushes are highly resistant to diseases and parasitic pests.

Propagation of the False Pistachio

Propagation by cuttings

The heel cutting method works best. You can choose when to do it: in spring (herbaceous cutting), in summer (semi-hardwood cutting) or in winter (hardwood cutting).

→ To learn all about the different types of cuttings, read Alexandra’s advice.

Sowing

The seeds are harvested in autumn. Place them in a well-draining substrate (such as seed compost) in a pot kept in the shade under a cold frame. Leave your pot outside in winter so the cold can stratify the seed. You may need patience, as staphylea seeds sometimes only germinate a year later.

Alternatively, Bladdernuts often self-seed in the garden if conditions suit them. Don’t hesitate to move young seedlings in autumn.

Removing suckers

Similarly, Staphylea occasionally produces suckers. Simply detach a sucker from the parent plant and replant it elsewhere in spring or autumn.

Layering

It’s possible to layer the lower branches of a Staphylea. Bend and pin a flexible branch to the ground. This will produce roots. You can sever, meaning separate the layer from the parent plant after two years of growth.

How to pair Staphylea?

The Staphylea pinnata will blend perfectly into a beautiful wild hedge alongside elder trees, hawthorns, rowans, medlars, guelder roses, serviceberries… as well as more colourful spring bushes like lilacs, roses (especially botanical varieties), and spring-flowering spireas…

The Staphylea colchica ‘Black Beauty’ with its very dark foliage will work wonders alongside trees and bushes with lighter, even golden foliage. For example, you could plant a Cercis canadensis ‘Eternal Flame’ with yellow, orange and red foliage in spring and autumn, and light green in summer, along with a Cornus alba ‘Aurea’ with golden yellow foliage for much of the year. At the base of the bladdernut, consider two types of creeping perennials: one with nearly black foliage to echo the False Pistachio, such as Bugle ‘Black Scallop’, and the second, by contrast, with yellow foliage like Brunnera macrophylla ‘Green Gold’.

Bottom right, a Staphylea pinnata, accompanied in a wild-inspired hedge by a serviceberry, a lilac, a common medlar, a ‘Black Lace’ elder and a hawthorn

Anecdotes

• In Georgia, on the shores of the Black Sea, the flower buds of Staphylea colchica are preserved in vinegar and take on the taste of capers;
• An oil that does not go rancid is extracted from the seeds of Staphylea trifolia. This oil is used in traditional pharmacopoeia in North America;
• The bony seeds were once used to make necklaces or rosaries;
• The stems laden with capsules in winter are sought after by creators of original bouquets.