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Hyssop

Herbaceous Perennial Flower, Herb

Hyssopus officinalis
Lamiaceae Family

This versatile perennial herb is often grown in containers, massed in perennial borders, or trimmed to form a low hedge in sunny formal gardens, knot gardens or along walkways. It's showy purplish-blue, pink or white flowers bloom from mid- to late summer.

	Site and Plant Characteristics
	Growing Information
	Varieties

Site Characteristics

Sunlight:

full sun

Tolerates partial shade.

Soil conditions:

tolerates droughty soil
requires well-drained soil

Grows in poor but well-drained soil. Will tolerate drought. Prefers alkaline soil but tolerates pH range from 5.0 to 7.5.

Hardiness zones:

3 to 10

May be managed as a semi-evergreen shrub in Zone 6 and warmer.

Special locations:

outdoor containers - Effective in window boxes or other containers since it can be kept trimmed to keep it in proportion.
rock gardens - Useful as low edging material.

Plant Traits

Lifecycle: perennial

Ease-of-care: easy

Height: 1 to 2 feet

Plants will grow to 2 feet if left alone but are easily trimmed to any height.

Spread: 1 to 3 feet

Bloom time:

mid-summer
late summer

Late June through August.

Flower color:

blue
violet
white
pink

Flowers are purplish-blue. Pink and white varieties are available.

Foliage color: dark green

Foliage texture: fine

Shape: upright

Plants are bushy. Easily pruned into preferred shape.

Shape in flower: same as above

Flowers borne on long, narrow, one-sided whorls in terminal spikes.

Special Considerations

Special characteristics:

non-aggressive - May self seed.
non-invasive
not native to North America - Native to south and eastern Europe.
evergreen - Semi-evergreen. Leave foliage intact in fall and cut back to the ground in the spring.

Attracts:

beneficial insects
butterflies

Special uses:

cut flowers

Growing Information

How to plant:

Propagate by seed, cuttings, division or separation - Divide plants in spring or fall.
Sow seeds in spring in a light, dry warm soil in full sun. Hyssop will self sow readily under favorable conditions.
For stronger plants, sow in a cold frame in the spring, where they will germinate quickly. Transplant to individual pots and overwinter in greenhouse or cold frame. Plant out late the following spring after danger of frost or early in the summer.
Cuttings of half-ripe wood in June to July will root quickly in a cold frame or greeenhouse. Plant out the following spring after danger of frost. Treat greenwood cuttings taken in April/May the same way.

Maintenance and care:

Plants do well in window boxes or containers and make attractive borders or edgings.
Plants are semi-evergreen, so don't prune in fall but wait and cut plants back to the ground in spring. Trim them through the growing season to maintain manicured appearance. Plants may need replacing every few years.
More growing information: How to Grow Perennials

Pests:

Nematodes

Varieties

'Alba' has white flowers.
'Rosea' has pink flowers.