Nepeta 'Six Hills Giant' – Planting & Care Guide

About Nepeta 'Six Hills Giant'

Nepeta × faassenii 'Six Hills Giant', commonly known as Catmint, is a vigorous, long-flowering hardy perennial valued for its masses of lavender-blue flowers and aromatic grey-green foliage. Its soft, billowing habit makes it particularly effective for edging paths, spilling over walls and weaving through mixed perennial borders.

From late spring through summer, numerous flower spikes rise above the foliage, creating a haze of blue-purple colour. Cutting the plant back after its first major flush encourages fresh growth and a second display of flowers later in the season. The nectar-rich blooms are particularly attractive to bees and other pollinating insects.

Growing approximately 60–90cm tall with a spread of 60–90cm, 'Six Hills Giant' is larger and more vigorous than many compact Nepeta varieties.

Planting Guide

• Plant in full sun for the strongest flowering and most compact growth.
• Will tolerate light partial shade.
• Prefers moderately fertile, well-drained soil.
• Suitable for loam, sandy and free-draining clay soils.
• Improve heavy soils with organic matter and horticultural grit.
• Avoid excessively rich soil, which can encourage soft, floppy growth.
• Dig a planting hole approximately twice the width of the root ball.
• Plant at the same depth as it was growing in its container.
• Backfill, firm gently and water thoroughly.
• Space plants approximately 60–75cm apart.

Care & Maintenance

Nepeta 'Six Hills Giant' is an exceptionally easy and dependable perennial.

• Water regularly during the first growing season.
• Once established, it is reasonably drought tolerant.
• Water during prolonged dry spells to maintain flowering.
• Feed lightly in spring if growing in poor soil.
• Avoid excessive fertiliser, as this can encourage sprawling growth.
• Apply a light mulch in spring while keeping it clear of the crown.
• Container-grown plants require more frequent watering.

Pruning

Cutting back is particularly beneficial with this vigorous variety.

• Remove faded flower spikes as required.
• After the main flowering flush, cut the plant back by approximately one-third to one-half.
• Fresh foliage should quickly develop, followed by further flowers later in summer.
• Cut remaining old stems back in late winter or early spring.
• Divide large or congested clumps every 3–4 years if necessary.

Growing Conditions

• Botanical Name: Nepeta × faassenii 'Six Hills Giant'
• Common Name: Catmint
• Plant Type: Herbaceous perennial
• Mature Height: Approximately 60–90cm
• Spread: Approximately 60–90cm
• Flower Colour: Lavender-blue
• Flowering Period: May to September
• Foliage: Aromatic grey-green
• Position: Full sun to light partial shade
• Soil: Moderately fertile and well-drained
• Growth Habit: Vigorous, spreading and mound-forming
• Hardiness: Fully hardy and very well suited to Irish gardens

Ideal Uses in the Garden

Nepeta 'Six Hills Giant' is particularly effective when planted in generous groups where its soft, flowing habit can develop naturally.

• Mixed perennial borders
• Cottage gardens
• Rose gardens
• Path edging
• Gravel gardens
• Pollinator-friendly gardens
• Coastal gardens
• Wildlife gardens
• Banks and slopes
• Informal ground cover

It combines beautifully with Roses, Geraniums, Salvia, Lavender, Echinacea, Rudbeckia, Verbena bonariensis, Alliums and ornamental grasses.

Seasonal Interest

• Aromatic grey-green foliage emerges in spring.
• Masses of lavender-blue flowers develop from late spring.
• Cutting back after the first flowering encourages a second flush.
• Flowers are highly attractive to bees and other beneficial pollinators.
• Soft, arching foliage provides attractive texture throughout the growing season.

Common Problems

Nepeta 'Six Hills Giant' is generally very healthy and trouble-free.

• Plants can become floppy or sprawling, particularly in rich soil or partial shade.
• Cutting back after the first flowering helps maintain a compact, attractive shape.
• Prolonged winter waterlogging can cause root and crown problems.
• Older clumps may become open in the centre and benefit from division.
• Slugs and snails generally cause little significant damage.
• Cats may occasionally roll on or flatten the aromatic foliage.

With its abundant lavender-blue flowers, aromatic foliage and long flowering season, Nepeta 'Six Hills Giant' is an outstanding perennial for Irish gardens. Particularly effective alongside roses and hardy Geraniums, it creates a relaxed cottage-garden effect while providing an excellent source of nectar for pollinating insects

• Size
  2L

Kindly be aware when mix/ mixed/ assorted/ varieties is mention you will receive ONLY ONE plant/ item, which will be selected for delivery, photos may show different varieties available - which may also vary 

 
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