Pyracantha Coccinea: What You Need to Know

Scarlet firethorn is a semi-evergreen plant that can be grown as a small tree, shrub, hedge, espalier and even as a groundcover. Buzzing bees adore the prolific white spring blooms and birds flock to the showy fall fruits. Unfortunately, birds have spread the seeds of this species beyond the garden gates in many areas, leading scarlet firethorn to be designated as an invasive species in some parts of the country.

Botanical Name: Pyracantha coccinea
Common Name: Scarlet Firethorn
Bloom Time: Spring
Light Needs: Full sun to part shade
Hardiness Zones: 5 or 6 to 9, depending on variety
Height: Up to 16 feet, depending on the variety
Growth Rate: Medium to fast

Scarlet firethorn is native to Southern Europe, the Caucasus region, and Turkey, but it's cultivated across the globe. This popular landscape plant is generally adaptable to a variety of garden environments, tolerates hedging well and is semi-evergreen. It's also a very showy plant that flowers abundantly in the spring, beginning in late April in the South and in May further north. While the white clusters of flowers may not smell so great to people, they are definitely pollinator magnets that are especially popular with bees.

The flowers grow into dazzling orange-red berries in the fall, which can completely coat the entire shrub. According to the National Capital Poison Control Center, Pyracantha coccinea fruit isn't considered toxic to humans or pets, but they can cause digestive upset, nausea and vomiting. On the other hand, Pyracantha fruit is a favorite fall snack for birds, including migrating songbirds like cedar waxwings. Unfortunately, birds can also spread the seeds of scarlet firethorn into natural areas, meaning this species has naturalized in some regions where it may displace native plants. (More on that below.)

How to Use Firethorn in Your Landscape

It seems like there's a scarlet firethorn for any situation — from large, sprawling hedges to a single focal plant in a compact front garden. Scarlet firethorn tolerates pruning extremely well and is usually grown as a loose hedge — probably because the thorny branches can be a pain (literally) to cut and clean up. Pyracantha can also make a nice small tree if left untrimmed or if limbed up. Scarlet firethorn is a great choice for gardeners with limited space and is easily trained against walls or fences as an espalier. If you love the look of a Pyracantha, but you're not into pruning, look for low-growing cultivated varieties that have been bred for their compact habit.

While scarlet firethorn will grow happily in part shade, it really needs full sun to flower and fruit at its best. This species is adaptable to many soil conditions and will tolerate fairly dry environments once it is established in the garden. Avoid permanently wet, poorly drained sites to limit health problems like root rot disease. Northern gardeners in USDA hardiness zones 5 and 6 should look for cold-tolerant varieties and site plants in full sun and protected areas to protect plants from cold damage.

Scarlet Firethorn Care

Get your Pyracantha off to a good start by planting properly. If it rains less than an inch of water a week during the first growing season, be sure to give your new shrub a good drink. After the first year of growth, your scarlet firethorn shouldn't need much attention beyond occasionally pruning and keeping an eye out for health problems.

Pruning

Scarlet firethorn is usually grown as a loose hedge. While firethorns handle pruning incredibly well, if you want flowers and fruits, avoid removing the older growth that will produce flower buds. Pyracantha sets its blooms on "old growth," which means that heavy-handed pruning at the wrong time of year can remove buds that would have grown into flowers in the coming season.

The typical guidance for pruning shrubs that bloom on old wood is the cut immediately after flowering in the spring. However, this practice will remove developing fruits and could diminish fall fruiting. Instead, shoot for one to three light trims during fall and summer to remove or train the vigorous new growth, which won't have fruit anyway. Keep an eye out for bird nests and avoid cutting into areas that have active nests with eggs or nestlings, especially if you're using mechanized equipment.

Pyracantha are some of the easiest plants to train into a wall-hugging espalier. Once young plants establish roots, branches can be tied to trellises or wires as a way to train growth into an ornamental pattern. New shoots that don't fit the espalier form can simply be pruned away.

Health Problems

Stressed plants that are growing in the wrong spot are more likely to have pest and disease problems. According to Michael Dirr's Manual of Woody Landscape Trees, scarlet firethorn are susceptible to fireblight, fruit scab, fruit rot, twig blight, leaf blight, root rot, aphids, leaf crumplers, lace bugs and scale insects.

Fireblight is the most serious disease that firethorns may deal with, and it can also spread to other plants in the rose family, including common ornamental plants like roses and hawthorns, as well as fruit trees, like apples, pears, peaches and plums. The disease is caused by the bacteria Erwinia, which can lead to branch dieback, cankers and even plant death. If you discover fireblight in your scarlet firethorn, prune 1-2 feet below affected branches and destroy the infected material. Be sure to sterilize your pruners between cuts to prevent spreading this disease.

Popular Scarlet Firethorn Varieties and Hybrids

There are lots of varieties of Pyracantha to choose from. A few good choices for small spaces, cold climates and especially colorful fruit are listed here.

For Compact Habit

• 'Red Cushion' — grows up to 4' tall with a mounding habit and develops deep red fruits
• 'Red Elf' — this hybrid may only reach 2' tall; bright red, persistent berries shine out against a backdrop of deep green leaves
• 'Silver Lining' — a mostly thornless hybrid that grows up to 3' tall and spreads up to 5' wide, depending on conditions; attractive variegated foliage eventually fades to green

For Cold Hardiness

• 'Baker's Red' — produces a heavy crop of red berries in the fall that may persist into the winter
• 'Firey Cascade' — in addition to good disease resistance, this hybrid also has especially good cold tolerance and abundant, showy and persistent orange-red fruits
• 'Government Red' — hardy to -5 degrees with abundant red fruits
• 'Orange Glow' — prolific white blooms lead to persistent and moderately large fall fruits that are resistant to fruit scab disease

Colorful Fruit

• 'Dart's Red' — this hybrid sets relatively large red fruits with good scab and fireblight resistance
• 'Gold Rush' — another hybrid selection with showy yellow fruits that are also resistant to scab disease
• 'Teton' — sets a crop of yellow-orange berries; this hybrid selection develops a more narrow, upright growth habit than the species (but may sprawl more in Southern climates); also fairly cold hardy and disease resistant

Is Scarlet Firethorn Invasive?

In the US, "invasive" plant species are non-native plants that are considered to cause harm to human health or other economic or environmental damage. Federal and state agencies designate invasive plants in their respective regions. When it comes to Pyracantha coccinea, some counties across the US as well as the state of Georgia have formally listed this plant as an invasive species. Other regions, like the states of California, Florida and Texas, have classified scarlet firethorn as being at risk for becoming invasive.

If you live in an area where scarlet firethorn is formally classified as an invasive species, you should grow something else. Folks in regions where scarlet firethorn has naturalized or where it's listed as a high invasion risk should also consider other options. Fortunately, there are several native species that can be grown in similar conditions and have a lot to offer in the landscape.

Chokeberry (Aronia spp.) – both red chokeberry (A. arbutifolia) and black chokeberry (A. melanocarpa) are broadly native to eastern North America; hardy in Zones (3)4 to 9; prolific white spring blooms develop into black or red fall fruits, depending on the species; glossy green foliage during the growing season with wine-red fall color; up to 5' tall with a slow, continual spread; look for varieties 'Brilliantissima' ('Brilliant'), 'Elata', and 'Viking'

Fragrant sumac (Rhus aromatica) – native to eastern North America and westward into South Dakota; hardy in Zones 3 to 9; short, lime-colored blossoms are held erect at the end of the branches; while the spring flowers aren't necessarily a showstopper, the glossy red berries they develop into are definitely attractive; glossy green leaves give way to fiery fall color; may grow up to 6' tall with a spreading habit, depending on the variety; 'Gro Low' only reaches about 3' in height

Native viburnums (Viburnum spp.) – regardless of the species, most viburnums provide prolific white spring blooms that are attractive to pollinators and develop into inky black, blue or purple fruits in the fall; most species will tolerate hedging and potentially even training, like espalier; plug in your zip code and search the National Wildlife Federation's Native Plant Finder for species of viburnum that are native to your region