Silverbush
Convolvulus cneorum
Silverbush is an evergreen Mediterranean shrub native to rocky coastal cliffs in Italy, Croatia, and Albania (and reported from Spain), prized for its intensely silver, silky-haired foliage and a long succession of white funnel-flowers with pink-flushed buds and yellow throats from spring into summer. It received the RHS Award of Garden Merit (confirmed 2017) and thrives in full sun, lean alkaline soil, and excellent drainage that echoes its wild cliff-face habitat. The honest catch is soil moisture: Convolvulus cneorum is acutely intolerant of wet, heavy, or waterlogged soil and routinely dies over winter in damp conditions or clay, making drainage the single non-negotiable site requirement.
Climate fit: narrow (21/100)
Border
Focal point
Container
Pollinator
Light
Full sun
Water
Low water
Mature size
24-48" tall · 36" apart
Hardy in zones
8a-10b
cold to mild winters
Native in Illinois
No
Convolvulus cneorum produces open, accessible funnel-shaped flowers typical of the Convolvulaceae, visited by generalist bees and hoverflies for nectar and pollen.
Cold hardiness
These values are location-based: this location's current hardiness is the baseline, and the 2050 value is a projected future climate for this same location.
Now
Zone 6b
Plotwright
USDA Zone 6b
-5°F to 0°F
Won't grow here
Zone 7a
Plotwright
0°F to 5°F
Won't grow here
In plain terms: This location has cold winters. Its winters are projected to keep warming through 2050.
✕
Out of range today and still out of range in 2050.
Heat tolerance
Heat tolerance values are location-based too: heat days today are observed at this site, and the 2050 value projects this same location under a future climate.
Loading AHS heat-zone data for this location...
Where this plant fits
Suitable across 39 ecoregions — 34 climate-resilient through 2070 · 5 newly possible by 2070. Best matches first.
Appalachian mixed mesophytic forests
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Appalachian-Blue Ridge forests
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Arizona Mountains forests
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Atlantic coastal pine barrens
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California coastal sage and chaparral
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Canadian Aspen forests and parklands
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Central Pacific Northwest coastal forests
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Central-Southern Cascades Forests
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Chihuahuan desert
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Chilean Matorral
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Plant this, not that
Better fit for this place
For Chicago, IL, these are replacement suggestions: similar plants with a stronger hardiness fit now and/or in 2050.
Hylotelephium 'Herbstfreude'
Autumn-joy stonecrop
A clump-forming herbaceous perennial grown for its showy late-season flower heads: masses of tiny star-like flowers borne in flattened cymes 3-6 inches across that emerge rosy pink, deepen to rose-red, and fade to coppery-rust as they die. Gray-green, fleshy, succulent-like leaves form upright clumps to about 2 feet. Easily grown in dry-to-medium, well-drained soil in full sun, it is drought tolerant and attracts butterflies, and its foliage and dead inflorescences persist into winter for added interest.
Better fit now and in 2050
Now: well-suited
2050: well-suited
Tagetes erecta
African marigold
A tall, bold warm-season annual from Mexico and Guatemala (the "African" name is a misnomer of its European garden history) grown for large, fully double, pompon-like flowerheads in saturated yellow, gold, and orange over strongly aromatic, finely divided foliage. Plants reach 12-48 inches and bloom from early summer to frost in full sun. The petals are edible and used as a culinary garnish and natural dye, and the flowers are the iconic "flor de muerto" of Mexican Day of the Dead. Despite the wide listed zone range it is frost-tender and grown for a single warm season.
Better fit now and in 2050
Now: well-suited
2050: well-suited
Leucanthemum × superbum
Shasta daisy
The classic white-and-yellow garden daisy — a clump-forming herbaceous perennial bearing showy single flower heads of white ray florets around a yellow central disc from midsummer into fall. A garden hybrid bred by Luther Burbank in the 1890s near snow-covered Mt. Shasta in northern California, it grows 2-3 feet tall and is a mainstay of the perennial border, cottage garden, and cutting garden. Easily grown in dry-to-medium, well-drained soil in full sun, it is drought tolerant, attracts butterflies, and is resistant to deer and rabbit browsing.
Better fit now and in 2050
Now: well-suited
2050: well-suited
Hydrangea serrata
Mountain hydrangea
Mountain hydrangea is a compact, deciduous flowering shrub native to the mountainous regions of Japan and Korea, where it grows in cool, moist, partly shaded conditions — and that cool mountain origin is the honest catch. Hardy through USDA Zone 6 when dormant, the plant breaks dormancy early and its new spring growth is reliably vulnerable to late frosts; a single late freeze in April can destroy an entire season's bloom on wood that would otherwise flower in midsummer. It is smaller and more refined than bigleaf hydrangea, with serrated leaves and distinctive lacecap flowerheads in blue or pink depending on soil pH, making it a graceful focal point for partly shaded borders where consistent moisture can be maintained.
Better fit now and in 2050
Now: well-suited
2050: well-suited
Similar plants
Browse lateral options with similar roles, light needs, size, or native-range overlap; these are not filtered for a better climate fit.
Coronilla valentina
Shrubby scorpion vetch
Coronilla valentina is a compact, evergreen Mediterranean shrub in the legume family (Fabaceae), with a native range spanning the Mediterranean Basin from Portugal and Spain through Italy, the NW Balkans and Greece to the Aegean and Turkey, and south across northwest Africa to Libya. In a warm, sheltered garden spot it rewards with prolific, intensely honey-scented yellow flowers from late winter into summer and handsome glaucous foliage year-round. The honest catch is cold-hardiness: RHS rates it H4 (hardy to about -10 °C), so it is borderline at the cold edge of USDA zone 7 and is liable to be cut to the ground or killed outright in a hard freeze, demanding a sheltered south- or west-facing wall in colder gardens — and the whole plant is toxic to humans and livestock.
Tecoma capensis
Cape honeysuckle
Cape honeysuckle (Tecoma capensis, syn. Tecomaria capensis; Bignoniaceae) is a vigorous, evergreen scrambling shrub native to southern and south-central Africa — from the Cape Provinces north through KwaZulu-Natal, Mozambique, Malawi, Tanzania, DR Congo, and Angola — valued for long, slender orange-to-apricot tubular flowers borne erratically across much of the year and attractive to nectar-feeding sunbirds. It reaches 2–3 m tall and wide as a free-standing mound, or considerably taller trained on a wall or trellis, and has received the RHS Award of Garden Merit. The honest catch is its frost-tenderness (barely survives to about 5°C; RHS H1C, roughly USDA 9b–11) combined with an invasive streak in mild climates: it suckers freely, self-layers, and has naturalised on the Azores and across coastal eastern Australia, so it must only be sited where its spread can be actively managed.
Tecomaria capensis
Cape honeysuckle
Cape honeysuckle (Tecomaria capensis, Bignoniaceae) is a vigorous, evergreen scrambling shrub from southern and south-central Africa, valued for tubular orange-to-apricot flowers borne erratically across much of the year. It reaches about 2-3 m tall and wide as a free-standing shrub, or can be trained much taller on a trellis or wall, and is widely used for informal hedging and as a hot-color border or container plant. It is frost-tender (RHS H1C; roughly USDA 9b-11) — in cooler climates it is grown under glass or as a summer container plant and overwintered indoors. In frost-free, mild climates it can become weedy: it has naturalised and is treated as invasive in parts of Australia and on islands such as the Azores, so site it where suckering and self-layering can be managed. It is not a recognised edible and is not flagged as notably toxic, though several plant parts feature in traditional southern-African medicine; treat it as ornamental rather than for consumption. Note the accepted binomial here is Tecomaria capensis (POWO/GBIF); the widely-seen Tecoma capensis is a synonym.
Camellia sasanqua
Sasanqua camellia
Sasanqua camellia is an evergreen shrub native to the forests of southern Japan — Kyushu, Shikoku, and the Ryukyu Islands — where it grows on forest margins and hillsides. In gardens it is prized as the earliest-flowering camellia, bearing fragrant blooms from September through January when almost nothing else is in flower, and it tolerates more sun and drought than its cousin Camellia japonica. The honest catch is cold hardiness: open flowers are blackened by hard frost, and the plant itself is reliably hardy only from zone 7a south, making it unsuitable for much of the northeastern and midwestern United States without meaningful shelter.
Agapanthus praecox
African lily
A bold, clump-forming evergreen perennial from South Africa, grown for big rounded umbels of trumpet-shaped blue (or white) flowers held on tall bare stalks above arching, strap-shaped leaves in mid-to-late summer. It is widely sold as "lily of the Nile," but that is a misnomer — the plant is South African (the Cape provinces and KwaZulu-Natal), not from the Nile. Spectacular and easy in warm climates, this evergreen Agapanthus is frost-tender, so in cold-winter areas it is grown in a container and overwintered under cover. The RHS has given several Agapanthus praecox forms its Award of Garden Merit and rates this evergreen species half-hardy (H3 — needs winter protection).
Tagetes erecta
African marigold
A tall, bold warm-season annual from Mexico and Guatemala (the "African" name is a misnomer of its European garden history) grown for large, fully double, pompon-like flowerheads in saturated yellow, gold, and orange over strongly aromatic, finely divided foliage. Plants reach 12-48 inches and bloom from early summer to frost in full sun. The petals are edible and used as a culinary garnish and natural dye, and the flowers are the iconic "flor de muerto" of Mexican Day of the Dead. Despite the wide listed zone range it is frost-tender and grown for a single warm season.
Educator packet
Plant packet
Silverbush educator packet
Silverbush is an evergreen Mediterranean shrub native to rocky coastal cliffs in Italy, Croatia, and Albania (and reported from Spain), prized for its intensely silver, silky-haired foliage and a long succession of white funnel-flowers with pink-flushed buds and yellow throats from spring into summer. It received the RHS Award of Garden Merit (confirmed 2017) and thrives in full sun, lean alkaline soil, and excellent drainage that echoes its wild cliff-face habitat. The honest catch is soil moisture: Convolvulus cneorum is acutely intolerant of wet, heavy, or waterlogged soil and routinely dies over winter in damp conditions or clay, making drainage the single non-negotiable site requirement.
Scientific name
Convolvulus cneorum
Plant type
shrub
Hardiness
8a-10b
Light
full-sun
Moisture
low
Spacing
36 inches
Classroom prompts
- Which plant traits are observations, and which are care recommendations?
- How would this plant fit change if the garden location moved warmer, colder, wetter, or drier?
- Which source-backed facts would you cite in a lesson handout?
Use the Sources & citations section below for page citation styles and the field-level source list.
Sources & citations
Cite this page
For lesson plans, articles, or research that uses this page. To cite a single upstream fact instead, use its specific source listed below.
Plotwright. (2026, May 17). Silverbush (Convolvulus cneorum). Retrieved 2026, June 30, from https://plotwright.com/plants/convolvulus-cneorum
Sources for every fact
Every fact on this page traces to a source. 18 fields cited - 18 source-backed.
RHS Find a Plant
Botanical research database
Backs 17 fields
Identity
Summary
Plant type
Light
Moisture
Hardiness
Heat zone
Size
Spacing
Habit
Design roles
Seasonal interest
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