Catmint is a popular accompaniment to roses with beautiful, vibrant blue flowers and an intensive fragrance. Here’s the correct way to plant and care for this flowering shrub.
The Nepeta genus, Catmint in English, includes around 180 deciduous shrub species, which are native to Europe, Asia and northern Africa. In nature, many grow in dry locations, but a few also grow in forests or on moist mountain slopes. However, only about 20 of these are used as ornamental plants in our gardens; these are popular for their decorative, generally gray-green foliage and their long flowering period. Catmint is also extremely easy-care and its flowers draw in swarms of all kinds of insects - so it’s no surprise that they were selected ‘Shrub of the Year’ by the ‘Bund deutscher Staudengärtner’ (Association of German Perennial Plant growers) as far back as 2010.
This undemanding plant is not only beloved by gardeners. Cats also adore this plant, which is how it derived the name Catmint. The velvet-pawed animals first sniff at the plant, rub and roll it into themselves and then become intoxicated for a few minutes. Unfortunately, the plant does not always come out undamaged.
Appearance and Growth
Catmint belongs to the Lamiaceae family. Its silver-gray to fresh green leaves stand opposite one another on the stem, meaning that two leaves are always at the same level, and have an intensive fragrance. Catmint flowers between April and July. Depending on the species and variety, it has violet, blue, white or pink-colored flowers on narrow inflorescences, which consist of countless individual flowers on up to 5 foot high stems.
Location and Soil
Most species of Catmint thrive best in sunny locations with barren, permeable soils and also tolerate dryness very well. These are primarily the gray-foliaged species. However, some species of catnip also thrive on fresh to moist, nutrient-rich soils, such as Japanese catmint (Nepeta subsessilis) or Pratt’s catmint (Nepeta prattii). Although these green-foliaged species don’t really like wet soils. While the majority of Catmints prefer sunny locations, these species thrive in off-sunny spots in the garden. The perfect soil for these species of Catmint has a pH value between six and seven, i.e. a neutral range.
The best times to plant Catmint are during the classic planting periods in spring and fall. In principle, you can plant the shrub throughout the entire season. However, when planting in the summer, bear in mind that Catmints should be regularly watered in the first weeks after planting. This is particularly important for green-leaved species which prefer moister soils. As Catmints love permeable soils, heavy, loamy soils should be improved with some sand before planting for better drainage.
If you prune back Catmint close to the soil after the main flowering, this stimulates the plant to flower a second time in late summer. This pruning measure also prevents the shrub from self-sowing - that is, if you don’t want it to self-sow. After pruning, provide Catmints with a fast-working, mineral fertilizer to give it sufficient strength for a second flowering.
The flowering volume of Catmint may diminish after three to five years. When this happens it should be rejuvenated through division in early summer. Catmint does not require fertilizing, however, it does the green-leaved species no harm to provide spring budding with a little compost.
Overwintering or Winter Protection
As outdoor bedding plants, the Catmint species at moderate latitudes are sufficiently winter-hardy, however in pots and containers they require additional protection, for example with brushwood or foliage as a layer over the root ball. Wrapping the pot with a coconut mat, fleece or blister padding prevents the root ball from freezing, a polystyrene disc prevents ‘cold feet’. Our tip: Prune back your catnip in the spring, not the fall. It’s fair to say that the dried seed stems of the Catmint are not as attractive as those of a blue giant hyssop or of the bear’s breeches, however, the dried plant parts serve as additional winter protection.
The lower species of this genus, such as the ‘Walker’s Low’ Catmint (Nepeta racemosa) are highly suitable for edging beds. The varieties ‘Superba’ and ‘Snowflake’, which form a thick cushion and thereby provide other bedding plants a beautiful violet or white frame, are particularly recommended. However, they can also be readily used for planting in pots and tubs. Taller species, such as the delicate growing Faassen's catmint, are a beautiful partner for Roses.
The violet varieties in particular form a great contrast to shrubs with fresh-green foliage and greenish-yellow flowers such as the Siberian Spurge (Euphorbia seguieriana ssp. niciciana). The delicate foliage also works really well with large-leaved species in shrub beds. As the plants of this genus are very robust and easy-care, they are often used as an alternative to Lavender. If you have a cat and would like to stop them trampling all over these plants, try the citron-fragranced species, such as the Common catmint (Nepeta cataria), as cats avoid this one.
Important Species and Varieties
The Faassen's catmint ‘Walkers Low’ (Nepeta x faassenii), has particularly conspicuous, dark-violet flowers and reaches a growth height of up to 35 inches. It was classified as excellent in the shrubbery review. The blue-violet flowering, large blossomed Catmint ‘Pool Bank’ (Nepeta grandiflora) is one of the tallest catmints with a growth height of up to 55 inches. It received the best assessment of all the species and varieties in the shrubbery review. The taller species are clump-forming and have an extremely delicate and relaxed appearance with their fine inflorescences and foliage. However, there are also lower, cushion-forming species. These include some varieties of Faassen's catmint, for example ‘Kit Cat’, and the catmint (Nepeta racemosa), whose varieties only grow between 7.87 and 15.75 inches tall.
Many species of Catmint propagate through self-sowing and appear again in some spots in the garden by themselves. However, propagation through division is more targeted and controlled. The best time is in the spring, during budding. This is most successful time, as the plants evaporate very little water from the leaves and it is not yet too warm outside. This also prevents water loss and poor growth. Here’s how: Dig up your Catmint with a spade at a sufficient depth and lift it out of the soil. Then separate the clump into several pieces spade. The number of clumps depends on the size of the clump. Then plant these in a suitable spot again and give them plenty of water in their new place. The varieties of Catmint can also be propagated through soft cuttings, as this propagation method also retains the properties typical for the varieties. The best time for this is early summer. Take cuttings around 2 to 2.76 inches long, remove the lower leaves and plant the offspring in a pots with potting soil.
Diseases and Pests
Catmint is generally considered extremely robust. The young Japanese Catmints are often nibbled at by snails. There is also the occasional risk of infestation from powdery mildew.
Frequently Asked Questions
When can I plant Catmint?
The best time to plant Catmint is in the spring or fall. You can also plant the shrub in summer, but then you must make sure it has plenty of water during the first week.
What does Catmint look like?
Catmint is a herby shrub with up to 55 inch tall stalks and silver-gray or fresh green leaves. The narrow inflorescences sit directly on the shoots and can be violet, blue, white or pink, depending on the variety.
Where does Catmint grow?
Catmint prefers barren and permeable soil with a pH value between six and seven, as well as a sunny spot. The shrub does extremely well in dryness.
What effect does Catmint have?
Experts assume that catmint has an intoxicating effect on cats. A typical reaction is for the four-legged animals to sniff at the plants and then rub or even roll in the plants. After this, they are generally intoxicated, which is often noticeable in their pronounced playful urges.
What Catmints are suitable for cats?
The white-flowered, Common catmint (Nepeta cataria), also known as Catnip, is particularly popular with cats. However, the widespread Nepeta x faassenii also has an effect on the velvet-pawed animals. In contrast, Catmints with a citrus fragrance are avoided.
Where can I buy Catmint?
Catmint can be bought as a garden plant in garden centers. Parts of the plant are also available dried or as a powder in pet shops or health food shops. Catmint fragrance sprays are also available.
How do I prune Catmint?
After the main flowering, prune the Catmint shoots back close to the soil.