Plant problems

Why Are My Phygelius Leaves Curling?

Q: Why are my phygelius leaves curling?

Phygelius (Cape figwort or Cape fuchsia) leaves curl most commonly in the UK because of drought stress, aphid infestation on the young shoot tips, or cold damage in hard winters that kills the top growth back to the base. Phygelius aequalis and Phygelius capensis are semi-woody, semi-evergreen subshrubs from the moist, rocky streamside habitats of South Africa; the many garden hybrids and cultivars bear pendant, tubular flowers in shades of red, orange, yellow, cream, and pink produced on branching panicles from June to October, making them among the longest-flowering of all UK garden plants for a sunny border. Both species and their hybrids are more or less hardy throughout the UK but behave differently in different climatic zones: in mild, coastal gardens in the south and west of England, Wales, and Ireland, phygelius retains a permanent woody framework and grows as a true shrub, reaching 1 to 1.5 m in height; in colder, more northerly gardens, the top growth may be killed to the ground by frost in winter and the plant regrows from the rootstock each spring as a herbaceous perennial, in effect behaving as a cut-back shrub similar to hardy fuchsia. Drought stress is the most common cause of leaf curl: phygelius grows naturally in moist conditions near streams and watercourses and the soft, flat leaves curl inward quickly when the root zone dries out, particularly in containers or in freely draining soils during hot UK summers. Aphids colonise the young shoot tips and flower stalks in spring and summer, causing leaf curl and distortion.

Q: Is phygelius hardy in the UK?

Phygelius is generally hardy throughout the UK but the degree of hardiness varies between species and cultivars and between UK climatic zones. Phygelius capensis and most of its cultivars are hardy to about -10 to -15°C; Phygelius aequalis and its hybrids are slightly less hardy (to about -8 to -12°C); the hybrid cultivars (Phygelius x rectus) vary in hardiness but most are reliably perennial in UK outdoor conditions. In mild UK gardens (coastal south and west), the woody stems survive most winters and the plant builds up into a substantial shrub over many years; in colder, more northerly gardens, the top growth is killed in winter but the rootstock survives to produce vigorous new shoots in spring. The flowering performance of phygelius is actually excellent in both scenarios: plants that are killed back to the ground in winter produce vigorous new growth from the base in April and May and flower abundantly from June or July onwards on the fresh shoots, sometimes performing even better than plants that have retained their old woody framework. In the coldest UK gardens (exposed upland areas in northern England and Scotland), the rootstock may be killed in very severe winters; protect with a thick mulch of composted bark around the crown in November. The popular cultivar 'Yellow Trumpet' (cream-yellow flowers), 'Salmon Leap' (orange), 'Devil's Tears' (red), and 'Moonraker' (cream-yellow) are all reliable in UK gardens.

Q: How do I grow phygelius in the UK?

Phygelius grows best in a sunny or lightly shaded position in moist, well-drained, fertile soil. Unlike many long-flowering summer shrubs (such as ceanothus and cistus), phygelius prefers moisture-retentive soil and suffers in dry conditions; a position that does not dry out in summer is important for sustained flowering performance. A sunny or semi-shaded south or west-facing border with moisture-retentive but well-drained soil is ideal; phygelius also does well in containers with regular watering. Feed with a balanced fertiliser in spring and a potassium-rich fertiliser (tomato feed) monthly from June to August to support the long flowering season. Regular deadheading of the spent flower panicles encourages a succession of new flowering stems throughout the summer and prevents the plant from directing energy into seed production. In mild UK gardens, phygelius can be left largely unpruned as a shrub; cut back in spring by about one third to encourage fresh, strong flowering shoots. In colder gardens where the top growth is killed by frost, cut the dead stems back to ground level in early spring (March to April) when new shoots are visible at the base; the plant will regrow vigorously and flower abundantly in the same season. Phygelius spreads gradually by stolons to form a colony; unwanted suckers from the colony can be dug out in spring to restrict spread, or transplanted to extend the planting elsewhere in the garden.

Q: Why is my phygelius not flowering?

Phygelius fails to flower well most commonly because it is in too much shade, because it has been pruned or cut back at the wrong time (removing developing flower buds), or because it is grown in too dry conditions which check the plant's vigour. Phygelius flowers on the current year's growth produced from late spring onwards; it is a reliably free-flowering plant in sun with adequate moisture and should produce its first flowers by June or July and continue into October in most UK gardens. If the plant is growing vigorously but not flowering, examine the following: shade is the most common cause (phygelius in deep shade grows well but flowers very poorly; it needs a minimum of 4 to 5 hours of direct sun daily for good flowering performance). Too-dry soil reduces flower production significantly; ensure the soil remains moist throughout the growing season, particularly during dry UK summer spells. Excessive nitrogen feeding produces leafy growth at the expense of flowers; switch to a potassium-rich fertiliser (tomato feed) from June onwards. Plants that have been cut back hard or frosted to the ground in spring should begin flowering by July or August as the new shoots develop; a brief delay relative to plants that have retained their framework is normal. If the plant is not flowering despite adequate sun and moisture, check whether it may have reverted: phygelius cultivars with coloured flowers occasionally revert to the plain species; the reversion shoots are often more vigorous and eventually outcompete the cultivar.

Phygelius (Cape figwort or Cape fuchsia) is one of the longest-flowering plants for a UK sunny border, producing pendant tubular flowers in red, orange, yellow, or cream from June to October. It grows as a permanent shrub in mild UK gardens and regrows from the rootstock after frost in colder areas. Drought stress is the most common cause of leaf curl; unlike many sun-loving shrubs, phygelius needs consistently moist soil to perform well.

Drought stress

Phygelius grows naturally in moist, streamside habitats in South Africa; the soft, opposite leaves curl inward quickly when the root zone dries out during hot UK summers, particularly in containers, in freely draining soils, or against south-facing walls where the soil dries out rapidly. Drought stress also reduces flower production significantly: the long flowering season that makes phygelius so valuable in the UK border depends on consistently moist growing conditions throughout summer. Plants in dry conditions flower briefly and poorly rather than continuously.

What to do

Choose a position in moisture-retentive but well-drained soil; avoid freely draining sandy or chalky soils unless enriched with substantial organic matter. Mulch the root zone deeply (10 cm of composted bark) in spring to conserve moisture through summer. Water during dry spells (more than 7 to 10 days without significant rain) particularly in the July and August peak summer heat. Container-grown phygelius needs watering every 1 to 2 days in warm weather; check the compost moisture daily and water when the top 5 cm is dry.

Aphids

Aphids colonise the young shoot tips and developing flower stalks of phygelius in spring and early summer; the leaves on affected shoots curl around the colonies and the shoot tips may be distorted. The soft, lush growth produced on cut-back plants in spring is particularly attractive to aphids. Natural predators typically control infestations within a few weeks; the vigorous new growth of phygelius in a good season quickly outgrows light to moderate aphid pressure.

What to do

On most occasions no treatment is needed; natural predators (ladybirds, lacewings, parasitic wasps) arrive within 3 to 4 weeks and reduce colonies significantly. Pinch off heavily colonised shoot tips. Apply insecticidal soap spray to young growth if the infestation is heavy; repeat every 7 to 10 days. Avoid high-nitrogen fertilisers that produce very soft, lush growth most attractive to aphids; switch to potassium-rich tomato feed from June to promote flowering over soft leafy growth.

Cold damage

Cold damage kills the top growth of phygelius in hard UK winters; the semi-evergreen leaves blacken and the soft stems die back, sometimes to ground level. In mild UK gardens, only the shoot tips and young stems are killed; in colder gardens the entire top growth may be lost but the rootstock typically survives and sends up fresh shoots in spring. The plant's behaviour after a cold winter, regrowing from the base as a herbaceous perennial, produces vigorous new flowering shoots that often outperform plants that retained their old framework.

What to do

Apply a thick mulch of composted bark (10 to 15 cm) over the root crown in November to insulate the rootstock from hard frost; this is the most important winter protection measure in colder UK gardens. Do not cut back dead stems until spring (March to April) when new shoots are visible at the base; the dead stems provide some insulation to the crown below. In spring, cut all dead stems back to ground level and the plant will regrow vigorously from the rootstock.

Waterlogging

Although phygelius prefers moist conditions, it does not tolerate waterlogged or persistently saturated soil; root rot can develop in anaerobic, waterlogged conditions, causing yellowing, wilting, and leaf curl that does not respond to further watering. The combination of wet soil and winter cold is particularly damaging and can kill the rootstock that would otherwise survive a cold winter in well-drained soil. Heavy, clay soils that become waterlogged in winter are the most risky for phygelius in UK conditions.

What to do

The ideal soil is moisture-retentive but well-drained: rich, humus-heavy soil that holds moisture without becoming waterlogged. On heavy clay, incorporate well-rotted compost and coarse grit to improve structure and drainage. Avoid low-lying positions that flood or remain saturated for weeks in winter. Raised beds improve drainage significantly for phygelius in clay-heavy gardens while still providing the moisture-retentive conditions the plant prefers.

Frequently asked questions

Why are my phygelius leaves curling?

Phygelius leaves curl most commonly because of drought stress (unlike many sun-loving shrubs, phygelius needs consistently moist soil; the soft leaves curl inward quickly when the root zone dries out), aphids on young shoot tips and flower stalks in spring and early summer, cold damage killing the top growth in hard winters, or waterlogging causing root rot in wet, heavy soils. In moist, sunny conditions phygelius is one of the most trouble-free and long-flowering UK border plants.

Is phygelius hardy in the UK?

Phygelius is generally hardy throughout the UK. In mild, coastal gardens it retains a permanent woody framework and grows as a shrub; in colder gardens the top growth is killed in winter but the rootstock regrows vigorously in spring, producing abundant flowers by July. The rootstock may need protecting with a thick bark mulch in the coldest UK areas. Most cultivars are reliably perennial in UK conditions.

How do I grow phygelius in the UK?

Grow in a sunny or lightly shaded position in moist, fertile, well-drained soil; phygelius needs consistent moisture throughout the growing season unlike most sun-loving shrubs. Mulch deeply in spring. Feed with balanced fertiliser in spring, then switch to potassium-rich tomato feed monthly from June. Deadhead regularly to extend flowering. Cut back dead top growth to the ground in spring; the plant regrows vigorously and flowers from July.

Why is my phygelius not flowering?

Phygelius fails to flower most commonly because it is in too much shade (needs at least 4 to 5 hours of direct sun), because the soil is too dry (reducing vigour and flower production), or because it has been fed too much nitrogen (promoting leafy growth over flowers). Switch to tomato feed from June. Plants cut back by frost in winter flower later (from July or August) than established shrubs but flower just as freely once new growth develops.