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Holly Olive and Its Virtues

Fortune’s Holly Olive is an appealing evergreen with highly fragrant spring flowers.

You might call osmanthus a great imposter, because shrubs and trees in the genus go by so many names.  At various times and places, osmanthus species have been tagged with common names like “false holly”, “tea olive”, “wild olive’ and even the scary-sounding “devilwood”. 

It takes some doing to get a handle on this group of ornamental evergreens.

Osmanthus species have nothing to do with Camellia sinensis, the species that provides black tea.  Nor are they part of the genus Ilex, home to hollies.  They really do not have any associations with the devil, though craftsmen find the hardwood devilish to work with.

The Latin name Osmanthus, is derived from the Greek words for fragrant and flower, so these common names probably fit it best.  Some of the common names reference olive, which provides another clue to their true nature.  Osmanthus is a card-carrying member of the olive family, Oleaceae, and its members are famous for the fragrance of their clusters of small, four-petaled flowers.

Experts reckon that there are about 15 species of holly olives, which are native to Asia and southern North America.  Some flower in spring, while others wait until fall, but all can thrive in home landscapes.  Smaller species may also be grown in large containers and overwinter inside in cold weather climates.

Autumn-Flowering Osmanthus

‘Goshiki’ is an especially pretty variegated holly olive.

In autumn, as the garden season starts to wind down, holly olive (Osmanthus heterophyllus, Zones 7-9) defies the seasonal trend and pumps out scores of small, white, four-petaled flowers.  Many of those flowers hide demurely under the foliage but make their presence known with a pervasive sweet scent.  Growing 8 to 10 feet tall and 7 to 9 feet wide, the species can be grown as a large, bushy shrub or standardized into tree form.  The leaves are dark green and spiny, like true holly, but close comparison reveals that holly olive leaves are opposite on the stems, while true holly leaves alternate.  Though the leafy branches can be used effectively in winter holiday arrangements and decorations, holly olive does not produce the bright red berries that characterize many true hollies. 

Many commercially available holly olive varieties bear green leaves, while others, like “Goshiki’ and ‘Kembu’ sport variegated leaves that are blotched or edged in cream.  Add light to the landscape with ‘Ogon’, which features bright, golden-green leaves.

Sweet olive has very fragrant flowers and more elongated, elliptical leaves.

 For something a little smaller and potentially more manageable in limited space, try sweet olive (Osmanthus decorus, Zones 6-9).  Native to areas around the Black Sea in Asia Minor, decorus grows only 6 to 8 feet tall, with tiny, white spring blossoms that perfume the air around the shrub.  The oblong foliage is spineless, glossy, and dark green. In fall, the shrubs produce small, purple-black fruits, a testament to the familial link between osmanthus and the rest of the olive family.

Good Fortune: Cross holly olive with fragrant olive and you get Fortune’s olive (Osmanthus x fortunei, Zones 7-10), which can grow 15 to 20 feet tall, with a rounded crown, but is easily pruned to fit smaller available spaces.  The hybrid has spiny, holly-like leaves and fragrant fall blooms.  One popular variety, ‘Fruitlandii’, is slightly more compact than its parent, with flowers that are creamy yellow instead of white.  ‘Variegatus’ offers green and white foliage, plus scented blooms.  Fortune’s olive offers better cold hardiness than some other osmanthus species.

Devilwood has deeply incised holly-like leaves.

Devilwood is a terrible name for (Osmanthus armatus, Zones 7-9), a lovely shrub native to China. Admittedly, the lustrous, holly-like leaves can be spiny on young plant but smooth out on mature specimens.   The characteristic white flowers appear in clusters, the better to spread their glorious scent in autumn. Female plants may also produce oval-shaped, dark purple fruits after the flowers drop. Devilwood is most often grown as a multi-branched shrub and can reach eight to 15 feet in height.  It is cold-hardy to at least Zone 7 and will tolerate more shade than many other osmanthus species.

Orange Supreme fragrant olive has an extra sweet spring fragrance and unsurpassed beauty.

In warm winter climates fragrant olive (Osmanthus fragrans, Zones 9-11), native to Japan and China, contributes strongly scented flowers to the spring garden, along with leathery oblong green leaves.  Maxing out at 10 to 15 feet tall and wide, it can be grown as a tree or shrub and pruned to keep the size under control.   Unlike holly olive, fragrant olive produces its white blooms in spring.  Like most other osmanthus, this spring charmer is relatively unfussy, tolerating clay soil and, once established, drought. The spectacular orange-flowered variety Osmanthus fragrans f. aurantiacus ‘Orange Supreme’ is one to seek out!

American wild olive is an underused native shrub. (Image by Homer Edward Price)

Osmanthus americanus (syn. Cartema americana, Zones 6-10), also known as American or wild olive is also sometimes referred to as devilwood.  The elongated leaves, which feature smooth rather than spiny edges are dark green and adorn shrubs that can top out at between 15 and 24 feet high.  As with other osmanthus, the fragrant flowers are white, blooming in mid-spring, followed by blue-purple fall fruits. Wild olive is quite cold-hardy.

Burkwood’s osmanthus (Osmanthus x burkwoodii, Zone 6) is relatively small (six to 10 feet tall and wide) hybrid with highly aromatic spring flowers.  Most often grown as a rounded shrub, the shiny, dark green leaves are toothed rather than spiny.  Introduced in England in the 1920’s, Burkwood’s osmathus has remained popular for its fragrant early flower clusters and is also reputedly deer resistant.

Planting Osmanthus

Osmanthus is easy to grow and tolerant of an array of conditions, but needs a good start in the garden.  Plant potted or balled and burlapped nursery specimens in soil amended with Fafard Premium Natural and Organic Compost.  Mulch thoroughly, but do not allow mulch to touch the plants’ main stems or trunks, and water regularly for the first few months while the roots get established.

Well-Mannered Groundcovers for Shade

Foamflower is a highly desirable native flowering groundcover for shade.

Back when one-size-fits-all gardening was a thing, ground covers for shade were seemingly as easy as one-two-three: creeping myrtle (Vinca minor), English ivy (Hedera helix), and Japanese spurge (Pachysandra terminalis). That is before they all began invading wildlands. All were neatly arrayed under an equally ubiquitous Norway maple or Bradford pear– both equally invasive and troublesome.

It was bound to happen. Introduce lots of vigorous, spreading plant species, and you increase the likelihood they will become pests themselves by invading local native plant communities. It did not take long for all three non-native, go-to ground covers to be added to the invasive plant lists of many U.S. states, particularly in the American Southeast and Northwest.

Unfortunately, going ubiquitous presented additional problems in the garden. As anyone who has ever tried to maintain the “perfect” lawn and garden can attest, mass plantings are easy pickings for mass invasions of pests and diseases. Japanese spurge loses a lot of its allure when it’s riddled with Volutella blight, as is all too common these days.

Well-Mannered Groundcovers for Shade

Fortunately, excellent (and arguably superior) ground cover alternatives abound, many of them native. Feeding the soil with quality compost, such as Fafard Premium Garden Compost Blend, at planting time will encourage good establishment from the start.

Twilight Aster

Twilight aster blooms for a long period in summer and fall.

Who says ground covers have to hug the ground? Some situations call for something taller. Twilight Aster (Aster x herveyi ‘Twilight’ (aka Eurybia x herveyi)) spreads by rhizomes into large swards of broad-leaved rosettes that give rise in summer to leafy 2-foot-tall stems. Plants are crowned with clusters of pale lavender flowers for many weeks in late summer and fall. An incredibly adaptable thing, ‘Twilight’ can handle situations from dry shade to damp sun. This eastern U.S. native goes dormant in winter.

Sedges

Many native sedges are evergreen and make lush groundcovers for shade.

Botanically speaking, they’re not grasses, but sedges provide much the same look for shade with their clumps of narrow-bladed leaves. Masses of low sedges such as Carex pensylvanica and Carex rosea (both eastern U.S. natives) make excellent low-foot-traffic lawn substitutes. For a bolder look, try a clump of seersucker sedge (Carex plantaginea), whose strappy puckered evergreen leaves contrast effectively with lacier shade subjects such as ferns.

Green-and-Gold

Green-and-gold is semi-evergreen and bears loads of bright golden blooms in spring that attract native bees.

Green-and-gold (Chrysogonum virginianum) is a hardy, attractive woodland native. “Green” references the dense spreading rosettes of fuzzy, crinkled, heart-shaped leaves that hold their color and substance through much of winter. The “gold” is provided by the numerous little yellow “daisies” that spangle the plants in spring and repeat sporadically until fall. Native to woodlands in the Southeast U.S., Chrysogonum virginianum is hardy well north of that, to Zone 5.

Robin’s Plantain

This is one of those rare plants you can plug into the garden just about anywhere – sun or shade.

Often occurring as a rather doughty lawn weed, this plantain (Erigeron pulchellus) is a nearly evergreen eastern U.S. native that occasionally assumes much more pulchritudinous forms. The cultivar ‘Lynnhaven Carpet’, for example, grows into handsome carpets of broad fuzzy gray-green leaves that are decorated in spring with pink daisies on 18-inch stems. It’s one of those rare plants you can plug into the garden just about anywhere – sun or shade. Another delightful selection of robin’s plantain is ‘Meadow Muffin’, with contorted leaves that give its rosettes a bit of a cow-pie look.

Allegheny Spurge

Allegheny spurge has leaves that are elegantly splashed with silver mottling, lending the plant a distinguished look totally lacking in Pachysandra terminalis. (Photo by Zen Sutherland)

Although not a rapid runner like the aforementioned Japanese spurge, our Southeast native Allegheny spurge (Pachysandra procumbens) far outdistances it as a desirable ornamental. The whorled evergreen leaves – arrayed in mounded 6-inch-tall clumps – are elegantly splashed with silver mottling, lending the plant a distinguished look totally lacking in Pachysandra terminalis. Things get even splashier in spring when conical clusters of frilly white flowers push from the ground, along with the fresh-green new leaves, as the previous year’s foliage fades. It’s one of those early-season garden scenes that makes your heart leap up. Allegheny spurge thrives in moist humus-rich soil, so give it a dose of Fafard compost if your soil is overly sandy or heavy.

Ragwort

Golden flowers light up this native naturalizer in late spring.

Golden ragwort (Packera aurea) and its near look-alike roundleaf ragwort (Packera obovata) provide quick cover for more informal garden areas. Low swaths of bright green rounded leaves emerge from their rapidly spreading roots in early spring, followed a few weeks later by heads of small yellow “daisies” on 2-foot stems. Use golden ragwort in moist garden situations, and roundleaf ragwort in moist to dry niches. They’re both native to much of central and eastern North America.

Creeping Phlox

This evergreen woodland creeping phlox (Phlox stolonifera) from eastern North America will expand into a ground-hugging carpet.

Don’t let its rather dainty appearance deceive you: this evergreen woodland creeping phlox (Phlox stolonifera) from eastern North America will expand into a ground-hugging carpet of small spoon-shaped leaves. It also provides a spring garden highlight when it opens its clusters of proportionately large round-lobed flowers, poised on 6-inch stems. Blue-, pink-, violet-, and white-flowered selections are available, but probably the best for ground cover is the vigorous cultivar ‘Sherwood Purple’.

Whorled Stonecrop

A native sedum that thrives in shade? Yes!

If you think stonecrops are drought-loving sun plants, you’re probably not acquainted with Sedum ternatum. Hailing from moist partly shaded habitats over much of central and eastern North America, it makes an excellent small-scale ground cover in similar garden conditions, although it also succeeds in sunnier, drier sites. Its dense low hummocks of fleshy ear-shaped leaves are studded with sprays of white flowers in spring. This highly effective shade plant is still rather rare in gardens – perhaps because of its family associations.

Foamflower

Frothy 6-inch spikes of white flowers appear in spring above spreading expanses of handsome maple-shaped basal leaves. These features of foamflower (Tiarella cordifolia), combined with a tough constitution, make for one of the best and most popular native ground covers for easter U.S. gardens. Its variety collina is a clumper rather than a runner, so it’s a better choice where a less rambunctious ground covering plant is required.

Barren Strawberry

Semi-evergreen leaves and bright golden spring flowers make this handsome bee plant a real winner in the garden.

Dense swaths of strawberry-like leaves expand steadily and tenaciously to provide attractive semi-evergreen ground cover in most any garden niche, from dry shade to full sun. Saucer-shaped yellow flowers dot the plants in spring, with a few repeat blooms later on. Recently moved to the genus Geum, barren strawberry (Waldsteinia fragarioides aka Geum fragarioides) is one of the best native ground covers for eastern U.S. gardens – under whatever name.