Catmint

A billowy ornamental herb with clouds of lavender-blue flowers, more compact and garden-worthy than true catnip. Catmint is a superb companion for roses and a drought-tolerant border plant that blooms for months when sheared after first flush. Less attractive to cats than true catnip, making it easier to maintain in the landscape.

Most garden catmint varieties are sterile hybrids that must be propagated by division or cuttings, not seed. Divide established clumps in early spring just as new growth appears, splitting into sections with several growing points each. Stem cuttings taken in early summer root easily in moist perlite. If growing species Nepeta from seed, sow indoors 8 weeks before last frost on moist compost surface. Germination takes 7-14 days at 18-22°C.

Catmint is one of the most reliable and rewarding perennials for any garden, forming billowy mounds 30-60cm tall covered in lavender-blue flower spikes from late spring through autumn. Unlike its cousin catnip, catmint (Nepeta x faassenii) is a sterile hybrid that does not self-seed, making it far better behaved in the garden. Plant in full sun with well-drained soil, spacing 45cm apart.

This Mediterranean-origin herb is exceptionally drought-tolerant once established, making it an outstanding choice for water-wise gardens, gravel gardens, and hot, dry borders. Water regularly during the first growing season to develop deep roots, then rarely if ever afterward. Catmint actually performs better in lean, dry conditions than in rich, moist soil.

The key to season-long flowering is the 'Chelsea chop'—shear the entire plant back by two-thirds after the first flowering flush fades, typically in early July. Within 2-3 weeks, fresh growth emerges and produces a second full display of flowers that continues into autumn. This simple technique doubles the ornamental value of catmint.

Catmint is the classic companion for roses, creating a billowy lavender-blue underplanting that perfectly complements pink, white, and red roses. The soft texture pairs beautifully with ornamental grasses, alliums, and hardy geraniums. In the vegetable garden, catmint's aromatic foliage helps repel certain pests while its flowers attract pollinators and beneficial insects.

Catmint thrives in lean, well-drained soil with a pH of 6.0-8.0. It tolerates poor, rocky, and chalky soils with ease—do not coddle this plant. Rich soil and heavy feeding produce floppy, split-open mounds that lack the tidy form catmint is valued for. Sandy loam or gravel-amended soil is ideal. No fertilizer is needed for established plants. A light top-dressing of compost in spring is more than adequate.

Ideal Temperature

Hardiness Zone Compatibility

Harvest catmint stems anytime during the growing season for fresh arrangements or dried crafts. For the most aromatic dried material, cut stems when flowers are fully open. The fragrant foliage retains its scent well when dried. Catmint is primarily an ornamental herb, so 'harvesting' is often simply the mid-season shearing that promotes reblooming—use the cut material for dried arrangements or compost it.

Storage & Preservation

Bundle cut stems and hang upside down in a warm, dark, well-ventilated space to dry. Dried catmint retains its pleasant herbal fragrance and makes attractive additions to dried flower arrangements and potpourri. The dried flowers and foliage keep their color well if dried quickly out of direct sunlight. Store in paper bags or open containers for potpourri use, or in airtight jars if using for herbal tea blends.

Troubleshooting Common Problems

Floppy, split-open mounds indicate too-rich soil or too much shade. Grow in full sun and lean conditions for the best habit. If plants do flop, the mid-season shearing solves the problem immediately. Failure to rebloom after shearing usually means the cut was too timid—shear back hard to about 15cm. Center die-out in older plants signals the need for division, typically after 4-5 years.

Growing Tips

1. Plant catmint in full sun for the best flower production and most compact habit. It tolerates light afternoon shade but becomes leggy and produces fewer blooms in shadier positions.
2. Ensure excellent soil drainage, as catmint is far more likely to die from wet feet in winter than from cold temperatures. In heavy clay soils, raise beds or amend generously with coarse grit and compost.
3. Space plants 45-60 cm apart to allow for their mature spreading habit. Catmint fills in quickly and tighter spacing leads to poor air circulation and potential fungal problems.
4. Water deeply but infrequently during the first growing season to establish a strong root system. Once established, catmint is exceptionally drought-tolerant and rarely needs supplemental irrigation.
5. Shear the entire plant back by one-half to two-thirds after the first bloom flush fades in early to midsummer. This simple step triggers a vigorous second and often third wave of flowers through autumn.
6. Avoid rich, heavily fertilized soil. Catmint performs best in lean to average soil, and excess nitrogen causes floppy, open growth that requires staking and produces fewer flowers.
7. Propagate by division in spring or early autumn every 3-4 years. Lift the clump, split it into sections with a sharp spade, and replant immediately. This also rejuvenates older plants that may have developed a dead centre.
8. Take softwood stem cuttings in late spring or early summer for additional plants. Snip 10 cm non-flowering shoot tips, remove the lower leaves, dip in rooting hormone, and insert into moist perlite. Roots form in 3-4 weeks.
9. Pair catmint with roses, lavender, salvia, and ornamental grasses for classic cottage garden combinations. Its soft blue flowers complement warm pinks, purples, and yellows beautifully.
10. Leave the final autumn bloom and dried stems in place over winter to provide habitat for beneficial insects and visual interest. Cut back to 5-8 cm above the crown in late winter or very early spring before new growth begins.