How to Grow Six Hills Giant Catmint

How to grow this minty ground cover

six hills giant catmint

The Spruce / Evgeniya Vlasova

Plant taxonomy classifies six hills giant catmint as Nepeta x faassenii 'Six Hills Giant'. Plant your six hills catmint in the spring through early fall. Once established, it begins flowering in late spring or early summer (depending on where you live) and will continue to bloom right into fall if sheared.

Six hills giant catmint is a drought-tolerant perennial, making it low-maintenance and a prime candidate for xeriscaping. It can be considered a showy herb because of its size—nearly 3-feet tall, with a similar-sized spread—and the number of blossoms it bears. This is a long-blooming perennial, making it a great filler plant if you're striving for a continual sequence of bloom.

Nepeta x faassenii is a plant that attracts butterflies and hummingbirds. It is both deer and rabbit resistant. The distilled oil is used in natural mosquito control.

Botanical Name Nepeta x faassenii
Common Name Six hills giant catmint, catmint, nepeta
Plant Type Herbaceous perennial
Mature Size 25-35 in. tall, 12-36 in. wide
Sun Exposure Full sun, part shade
Soil Type All, but prefers well-draining
Soil pH Alkaline
Bloom Time Early summer to early autumn, depending where you live
Flower Color Purple
Hardiness Zones 3-8 (USDA)
Native Area Africa, Europe, and Asia

Six Hills Giant Catmint Care

Nepeta x faassenii is a herbaceous perennial. It is also considered an herb with medicinal properties: the genus having been used in folk medicine for centuries as a sedative or for digestive issues.

A fragrant plant, the grey-green leaves of Nepeta x faassenii may be harvested and dried for use in potpourri. The violet-lavender flowers are small but numerous, and they are shaped like little trumpets. Growth habit is mounding.

As a plant that craves a well-drained soil, it's natural for rock gardens. If you were to mass several plants together in a small area, Nepeta x faassenii could serve as a flowering ground cover that would suppress weeds, since they do produce dense growth. You can also use it as an edging plant to line a pathway or border.

closeup of catmint

The Spruce / Evgeniya Vlasova

six hills giant catmint

The Spruce / Evgeniya Vlasova

closeup of catmint

The Spruce / Evgeniya Vlasova

Light

Six hills giant catmint prefers full sun or part shade.

Soil

Six hills giant catmint will do well in most soil but thrives when it's well-draining.

Water

This plant has average watering needs; water about 1-inch weekly.

Temperature and Humidity

Grow the six hills giant catmint in planting zones 3-8. Catmint doesn't thrive in too-hot climates, like the American deep South. More temperate regions produce better plants.

Fertilizer

Six hills giant catmint has no special fertilizing needs.

Catmint vs. Catnip

Catmint is often mistaken for catnip; cats like both (though they prefer catnip) and both plants belong to the same genus, Nepeta. The difference? Nepeta cataria is catnip, while Nepeta mussinii is catmint. Catnip has a more bushy, weedy appearance and has white flowers; catmint has lavender flowers and prettier foliage, making it a perfect choice for your perennial bed.

Varieties

Six hills giant catmint is itself a variety of Nepeta, but there are many other Nepeta varieties that thrive in your garden:

  • 'Siberian catmint': boasts large green foliage and blue flowers
  • 'Yellow catmint': features yellow blooms
  • 'Faassen's catmint': has silvery foliage and blue flowers
  • 'Walker's Low': shows dark lavender flowers and grey-green leaves
  • 'Japanese catmint': offers clusters of lavender-pink flowers and reaches 2-feet tall

Pruning

Six hills giant catmint only needs pruning once a year, after it's bloomed, in late fall or early winter. Wait till the plant has gone dormant, after a few touches of frost, and cut back the entire plant with clean gardening shears, so it's 2 to 4-inches high.

Propagating Six Hills Giant Catmint

Divide this perennial in spring every few years to propagate it and/or to revitalize it. Since the plant stems can end up leaning away from the middle after a certain height is achieved (leaving a hole in the center of the clump), you may wish to support with a metal ring (as for peonies) or with stakes and twine.

How to Grow Six Hills Giant Catmint From Seed

Seeds from six hills giant catmint grow well if they're sown directly into the outdoor soil, right before the last expected frost date in your region, spaced about 1-foot apart from each other in a sunny area. Water regularly to make sure they germinate, and remember that this plant doesn't always bloom in its first year.