How to Grow Six Hills Giant

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Six Hills Giant

Nepeta × faassenii 'Six Hills Giant'

herb

Six Hills Giant is a vigorous catmint cultivar prized for its abundant lavender-blue flowers and aromatic foliage. This hybrid nepeta is a robust perennial that attracts pollinators and thrives in sunny, well-drained gardens. It grows taller and more robust than standard catmint varieties, making it an excellent choice for borders and informal gardens.

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Example Six Hills Giant timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Six Hills Giant

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Six Hills Giant

    Around Jun 16

    ≈ 60 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Six Hills Giant dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily
💧
Water: Drought tolerant once established; water moderately during growing season. Reduce watering in winter. Prefers dry to medium moisture levels; avoid overwatering.
📏
Spacing: 24 inches
📅
Days to maturity: Flowers within 60-90 days from transplant
🌱
Planting depth: Plant at soil level; do not bury the crown

Soil

Type: Well-draining loamy or sandy soil
pH: 6.0-7.5
Amendments:
Compost Grit or perlite for drainage Aged manure

Growing Zones

Find your zone →

Thrives in zones 4-9, with reliable growth even in zone 3b

3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a

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Growth Stages

1

Seedling/Transplant

2-4 weeks

Young plants with soft green foliage and minimal branching.

Keep soil lightly moist until established (2-3 weeks). Harden off transplants before planting outdoors. Plant in spring or fall.

2

Vegetative Growth

4-8 weeks

Plant rapidly develops multiple stems and bushy foliage; aromatic, finely-textured gray-green leaves emerge.

Water moderately and ensure excellent drainage. Pinch back tips in early season to encourage branching and bushier form.

3

Flowering

June-September (3+ months)

Dense spikes of lavender-blue flowers appear on elongated stems above the foliage.

Deadhead spent flowers regularly to encourage continuous blooming through summer. Provide full sun for best flowering. Drought stress improves flower production.

4

Seed Production

August-October

If not deadheaded, flowers fade and develop small seed pods.

Allow some flowers to set seed for self-seeding if desired, or deadhead to redirect energy to new blooms.

5

Winter Dormancy

November-March

Foliage dies back in cold climates; in mild areas, foliage may persist but growth halts.

Cut back to 4-6 inches in late fall (zones 6 and colder) or leave standing through winter for structure. Ensure no standing water at crown.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Plants requiring consistently moist soil Hydrangeas Hostas Astilbe

Common Pests

  • Increase humidity by misting; spray with water or insecticidal soap if severe. Avoid over-fertilizing with nitrogen.

  • Strong water spray to dislodge; neem oil or insecticidal soap. Encourage natural predators like ladybugs.

  • Improve air circulation. Spray with sulfur dust or baking soda solution. Remove affected leaves. Avoid overhead watering.

Uses

🍳

Herbal Tea & Flavoring

Culinary

Fresh or dried catmint leaves make a fragrant, calming herbal tea with a minty-floral flavor. Leaves can also be used to flavor desserts, beverages, and light savory dishes. [source]

💊

Digestive & Relaxation Aid

Medicinal

Traditional herbalism uses catmint to support digestion, reduce anxiety, and promote relaxation. Contains compounds like nepetalactone with mild calming properties. [source]

🦋

Pollinator Magnet

Wildlife

Abundant flowers attract bees, butterflies, hoverflies, and other beneficial insects throughout the season, making it essential for pollinator gardens. [source]

🏠

Cut & Dried Arrangements

Household

Flowers dry beautifully and retain color and fragrance, making them ideal for dried floral arrangements, wreaths, and craft projects. [source]

🎨

Fragrant Sachets & Potpourri

Craft

Dried leaves and flowers retain strong aromatic oils, perfect for creating fragrant sachets, pot-pourri, and herbal crafts. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Cut flowering stems for fresh arrangements or drying throughout the bloom season. For dried flowers, harvest when blooms are fully open but before they fade, then hang-dry in a cool, airy location. For culinary or medicinal use, harvest leaves in early morning after dew dries, pinching from stem tips.

Fun Facts

  • 🌱 Six Hills Giant is named after the English gardens at Six Hills Nursery in Hertfordshire, where the cultivar was developed and selected for superior vigor.
  • 🌱 Catmint is famously attractive to cats; many cats will roll in and rub against the plant, bruising leaves and releasing more of the nepetalactone scent they love.
  • 🌱 Unlike true mint, catmint is not invasive and does not spread via underground runners, making it a well-behaved garden perennial despite its enthusiastic growth.

Gardening Terms

New to gardening? Learn about terms used in this guide:

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