Bells of Ireland is a semi-hardy annual in the mint family, native to the Caucasus mountains and noted for producing a mid-summer to fall bloom of showy, fragrant, white flower spikes. Cup-shaped green calyces encase the flowers and are densely packed along each flower spike from top nearly to base. Tiny stem thorns are sharp to the touch. Calyces remaining attractive to late summer before turning beige. The genus name refers to the Moluccca Islands off Indonesia where these plants were once thought to be native. The species name means smooth. Bells of Ireland performs best in cool summer climates, sited in full sun, in well-drained, consistently moist, loose and moderately fertile soil. It will tolerate light shade and poor soil with good drainage. It would probably not do well in a hot, humid climate. This is an excellent plant for fresh cut or dried flower arrangements. For dried flowers, it is best to cut flower stems prior to seed ripening and hang the stems in bunches in dry places with good air circulation. You can sow seed outdoors a few weeks before the last frost date, or, in warm winter climates, you can sow in fall. Seed can be started indoors about 8 to 10 weeks before last frost date, but plants do best when started outdoors. Bells of Ireland can benefit from an application of fertilizer for larger spikes and stakes to prevent sprawl. Cut stems prior to seed formation to prevent self-seeding. Bells of Ireland is not native to Ireland. The common name probably refers to the green color of the calyces. Diseases, Insect Pests, and Other Plant Problems: No serious diseases or insect pests. Hot and humid summers can be a problem.
Curated pairwise relationships between this plant and others in the library — who feeds
whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.
No curated interactions recorded for this species yet.
Also noted by NC State
Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell
apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.
Full sun (6 or more hours of direct sunlight a day) | Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Clay; High Organic Matter; Loam (Silt); Sand
Soil pH
Acid (<6.0); Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Moist | Occasionally Wet
Available space
12 inches-3 feet
NC region
Coastal; Mountains; Piedmont
Mature size
Height: 2 ft. 0 in. - 3 ft. 0 in. | Width: 1 ft. 0 in. - 1 ft. 6 in.
Growth rate
Rapid
Maintenance
Low
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Habit / form
Erect
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Opposite
Leaf shape
Ovate
Leaf margin
Crenate
Leaf size
1-3 inches long
Hairs present
No
Leaf detail
Light green leaves, 2 1/2 inches long, ovate, crenate, and scalloped.
Flower color
Green; White
Flower value
Fragrant; Good Cut; Good Dried; Showy
Flower form
Spike
Flower shape
Cup
Flower detail
Showy flower spikes featuring fragrant but tiny white flowers of little ornamental significance encased by large, showy, cup-shaped, green calyces. Blossoms from July through September.
Bloom time
Fall; Summer
Fruit type
Nut
Bark detail
Branching square stems.
Stem color
Green
Wildlife & Ecology
Native status
Non-native
Origin
Eastern Mediterranean to India.
Distribution
Western United States, Texas, Pennsylvania, Spain, and Portugal.