'Purple Haze' giant hyssop is a hybrid cultivar in the mint family (Lamiaceae) It will grow 2-3 feet tall and 1-2 feet wide in very well-drained soil in full sun. Raised beds or containers provide drainage if you have heavy clay soil. Do not overwater or fertilize. Spikes of tubular flowers create a bluish-purple hazy especially when several are planted together. Bloom time is early summer to fall. The aromatic foliage deters deer browsing. Use near the front of the border of a native/pollinator garden, rock garden or container and watch as the pollinators flock to the flowers. Insects, Diseases, and Other Plant Problems: No significant problems. Leaf spot, powdery mildew, and rust are occasional problems. Poorly drained soils will lead to crown rot. More information on Agastache .
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.
Fills a similar nicheAgastache 'Astello Indigo'Agastache 'Blue Boa'Buddleja Lo & Behold® 'Blue Chip Jr.'
Full plant profile
Growing Conditions
Plant type
Herbaceous Perennial; Perennial
Life cycle
Perennial
USDA zones
6a, 6b, 7a, 7b, 8a, 8b, 9a, 9b
Light
Full sun (6 or more hours of direct sunlight a day)
Soil texture
Loam (Silt); Sand; Shallow Rocky
Soil pH
Neutral (6.0-8.0)
Soil drainage
Good Drainage | Occasionally Dry
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. - 2 ft. 0 in.
Growth rate
Medium
Maintenance
Low
Canopy layer
4 - Herbaceous (3-15 ft)
Form & Appearance
Leaf color
Blue; Green
Leaf type
Simple
Leaf arrangement
Opposite
Leaf shape
Lanceolate; Ovate
Leaf margin
Serrate
Leaf value
Fragrant
Hairs present
No
Leaf detail
Fragrant blue-green leaves are lance-shaped to ovate.
Flower color
Blue; Purple/Lavender
Flower value
Fragrant; Long Bloom Season; Showy
Flower form
Spike
Flower shape
Tubular
Flower size
< 1 inch
Flower detail
Spikes of blue-purple tubular flowers in summer to fall