Six Hills Giant catmint: a loose blue-violet border

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A large catmint with a loose outline

Six Hills Giant combines small grey-green leaves with long flower stems bearing many small blue-violet lipped flowers. The foliage grows in pairs and has crenate margins. The cultivar name is independently documented; the RHS profile lists Nepeta 'Six Hills Giant' and gives Nepeta × faassenii as a synonym attribution. Both names refer to the same catmint. In a developed planting the perennial looks loose and broad. It suits a sunny perennial border where arching shoots can stand out without completely obscuring a narrow passage.

Young plants leave room for growth

The linked child offers contain 9 cm pots with approximately 10–25 cm total height including the container. Quantity depends on the set selection. Their slender young shoots do not yet have the height and width of a developed Six Hills Giant. Approximately 50–100 cm height and similar width are a cultivar guide for the later planting; the more modest shop figures describe a possible cultivated form rather than a fixed maximum. Check the root ball when unpacking and initially place the plants in a bright position. A young delivered plant without flowers is consistent with its stage of development.

Allow for the later arch beside a path

Sun or bright partial shade and well-drained soil are suitable. In a sunny position the loose habit is usually easier to accommodate than in cramped, damp shade between large neighbours. Approximately 60–90 cm spacing is a practical garden guide; plan according to later width rather than current pot size. Beside a path, a slightly set-back planting position lets the flower stems extend over the border edge. A discreet support may be useful depending on position and growth. A dense, tightly tied bunch would alter the natural shape.

Establishment comes before drought tolerance

Plant in mild weather in frost-free, workable soil. Spring or autumn provide suitable opportunities as long as the soil is neither waterlogged nor completely dry. Set the root-ball surface at its previous level and water thoroughly. Check the small original root zone over the following weeks. An established Six Hills Giant tolerates drier periods, but a young 9 cm root ball initially explores very little garden soil. Permanent container growing needs more root space and an open drainage outlet. Even a drought-tolerant perennial planting needs attentive care in a hot container.

Resetting after the first flowering

When the first main flowering fades and the stems fall apart, cutting back can make the shape more compact and encourage further flowers. Cut back faded shoots without unnecessarily damaging healthy young growth at the base. Water as needed if the soil is dry afterwards, so new shoots do not immediately begin with an inadequate water supply. Renewed flowering depends on the season, weather and plant and is not guaranteed. Removing only individual troublesome shoots initially retains more of the existing loose appearance, but gives up a uniform fresh start for the border.

Grey-green is not automatically a problem

The soft grey-green leaf colour is normal for catmint. A new white coating may instead indicate powdery mildew, especially in dense growth. Check leaves and shoots and keep the planting accessible. Leafhoppers can also occur; stippled leaves therefore need closer inspection rather than just additional water. Feed moderately according to soil and growth. Plenty of nitrogen may encourage long, soft shoots and does not turn a broad variety into a small, compact edging plant. Yellow or wilted foliage is initially a reason to assess roots, moisture and possible damage together.

Retreating in winter and restarting in spring

The perennial largely dies back above ground in the cold season. An empty border space is therefore not equivalent to a failed summer delivery. Remove dead remains in line with new growth and, especially in containers, ensure free drainage and a protected root ball. On frost-free days it must not dry out completely. Older dense clumps can be divided in spring or autumn; division reliably retains the named selection. Young set plants do not yet need this measure. Their first care priority remains a well-prepared position with spare space.

One plant, several views

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