Catmint (Nepeta spp. and cvs., USDA Hardiness Zones 38) has a way of lifting my mood. This plant impresses me because it can stand out in even the most hostile circumstances, whether it’s along a cobbled walk in England or in the median planters that line Chicago boulevards. Over the course of several weeks in the summer, the beautiful lavender-blue blossoms appear to shine just as brilliantly in the garden as they do above a hard expanse of concrete and macadam. The easiest catmint delight for me, however, is seeing my cat Boo fall prey to its seductive charm.
Despite the fact that some varieties have been misused to the point of ubiquity, I have a lasting affection for catmint. And it was because of this affection that I wanted to try as many different kinds as I could in order to determine which ones were the greatest. It’s true that when catmints are mentioned, many gardening buddies scrunch up their faces. Now, while I freely acknowledge that I won’t mind if catmint and Knock Out roses (Rosa ‘Radrazz’, Zones 49) never see another planting, I’m not quite ready to give up on this wonderful collection of hardy perennials. This is particularly true of a few particular varieties that stand out for their durability, seemingly endless blooms, and attractive leaves.
Top performers
In terms of bloom time, general habit, disease resistance, and low maintenance requirements, these types were picked as the best.
The most well-liked plant in this genus is undoubtedly “Walker’s Low” (N. racemosa ‘Walker’s Low’, top photo), based on its popularity and the numerous prizes it has won. Walker’s Low is taller than one might anticipate at 30 inches. The name does not represent its size; rather, it relates to the garden in Ireland where it first appeared. One of the most magnificent floral displays ever is produced by luminous blue blossoms that are carried in upward-curving plumes up to 12 inches long. The attractive gray-green leaves are completely hidden by the flowers for several weeks when they are in full bloom in late April. Walker’s Low pairs beautifully with a range of perennials and is essential for softening sharp edges along patios and paths. In my garden, “Walker’s Low” and Japanese roof iris are a favorite combination (Iris tectorum, Zones 59). I adore the way the delicate, billowy catmint contrasts with the broad, spiky iris leaves, as well as the color echo of the lavender-blue blossoms.
The flower and foliage of “Sweet Dreams” (N. subsessilis ‘Sweet Dreams’) are a welcome change from those of other catmints. From early summer to late fall, charming pink blooms are arranged in generous clusters and tastefully complemented with burgundy bracts. By catmint standards, each trumpet-shaped blossom is 1 inch long, which is quite large. The lush green foliage will surprise you if you assume this is simply another catmint with gray-green leaves, especially when it turns colorful in the fall. Despite being a large plant, “Sweet Dreams” remains compact throughout summer. In contrast to other catmints, Japanese catmints (N. subsessilis and cvs.), such as “Sweet Dreams,” like wet soils and partial shade, though they are equally comfortable in full sun. However, deadheading is necessary to prevent “Sweet Dreams” from having a nightmare appearance after the first flush of blooms since the brown, spent flowers persist.
When great gardeners are honored with magnificent plants, it is lovely. Such a plant is called “Joanna Reed” (N. ‘Joanna Reed’), after the late Pennsylvania gardener who discovered it. One of the neatest catmints I’ve ever produced, and this quality secured a perfect score in our testing. It didn’t require deadheading because of its sturdy stems, which never flopped, and because new growth appeared swiftly to cover the wilting flower stems. I find it impossible to imagine “Joanna Reed” without blooms because of the constant display of huge violet-blue flowers that cover the wide-spreading, compact plants from spring into October. Many catmints boast about the attractiveness and unpalatability of their dusty green foliage.
Greek catmint (N. parnassica), according to a short internet search, is more popular in European gardens, but it’s still worthwhile to look for this rare beauty here. Greek catmint is robust and audacious. However, the stems of our test plants only grew to a maximum height and width of 4 feet. Stems up to 6 feet tall are possible. The tint of the fragrant leaves lies midway between green and gray-green. Beginning in early summer and continuing into early October, long spikes of tiny lavender blooms, each less than half an inch long, are densely populated. Greek catmint has the presence to dominate any garden and will cheerfully take all the sunlight you can throw at it.
I believe the catmint “Six Hills Giant” (N. “Six Hills Giant”) is the standard by which all other catmints should be measured. The word “giant” is used to indicate the massive plant size and the extravagant floral display. Long flower spikes attract attention starting in late spring. However, like many catmints, ‘Six Hills Giant’ may start to relax or even recline a few weeks into the flowering period. This was true in our testing. After the initial flower flush, don’t be afraid to bash it back to promote the growth of new, stronger stems. Although it may be difficult to consider giving up blossoms, there will be many more to come. For the ideal display, place “Six Hills Giant” next to virtually anything pink in the garden.
Select Blue (N. faassenii ‘Select Blue’), chosen for its blue flowers, is a superior addition to the group of long-blooming catmints. From midspring to midfall, I don’t think we experienced a day without flowers. The flowers are actually lavender with a darker calyx that gives them a swarthy appearance, despite claims that they are a darker blue than the straight species (N. faassenii). Late into the season, the low, mounded habit remained compact without shearing. For its tenacity and resistance to drought, the xeriscape specialists at High Country Gardens in New Mexico advise “Select Blue,” and we can vouch for its impressive performance in typical garden settings as well.
Getting down to the nitty-gritty of catmint
Catmints are tough, free-flowering perennials that typically like full sun and well-drained soils for growth. However, some are well-liked for xeriscaping because, once established, they can withstand drought. When lavenders are not hardy, they are often referred to as “poor man’s lavender (Lavandula spp. and cvs., Zones 59), which is an acceptable analogy. Here are some additional details concerning this category of plants that you should be aware of.
Catmints are incredibly floriferous from early spring to the end of the growing season. Their unique tubular, two-lipped blossoms identify them as belonging to the mint family. Even when the flowers have faded, colorful calyces still improve the floral arrangement.
Through slicing off a piece of an established clump with a spade, you can proliferate by spring division. There should be numerous young shoots and a sizable root system in each fresh division. Catmint cuttings will take root quickly if they are cut from healthy shoots before the flower buds appear. The cuttings should take several weeks to root if you place them in a moist medium like sand or a peat-perlite mixture.
An essential oil found in the leaves and stems causes cats to exhibit a range of behavioral reactions. Eating the leaves may have calming effects, while rubbing, licking, or biting them creates a momentary high. According to all accounts, cats are especially intoxicated by catmint, or catnip (N. cataria*). You unfortunately have limited options for preventing cats from mauling (and occasionally squashing) your plants. Although most plants will recover fast following an attack, barriers may be your only alternative.
Although Japanese catmints (N. subsessilis and cvs.) prefer moist soils and don’t mind partial shade, wet or soggy areas can be the death knell for most catmints. Catmints frequently appear on lists of deer-resistant plants because they are rarely troubled by disease or pests.
It’s simple to ignore the leaves when there are so many blooms to catch your attention. Many catmint species are known for their fuzzy, gray-green leaves, although some, like Siberian catmint (N. sibirica), have huge, green leaves instead. Finding it difficult to tell if something is catmint? Another distinguishing characteristic of the mint family is square stems.
High fertility merely promotes floppy behavior. Simply shear the older stems down to the young leaves coming from the crown when stems start to flop over and flower output begins to decline. Plants that have been sheared will recover in a few weeks and resume their natural appearance.
Catmint should only be pruned in the spring or once you are certain that the growing season has ended, as it can be ugly in the winter. Even late in the growing season, cutting it back stimulates it to resprout, and the new growth is cold-sensitive. Any potential winter damage is avoided by waiting until spring.
New kids on the block
The following catmints are brand-new to the experiment, but I’m eager to see how they grow over the coming years because of their promising start.
1. ‘Blue Dragon’ (N. ‘Blue Dragon) has delighted me ever since I first saw its vivid blue-purple blossoms in 2010. A profusion of huge flowers (11/4 inches long) that bloom from late spring to mid-fall attract a lot of butterflies and bees. The breathtaking floral arrangement resembles sage (Salvia spp. and cvs, Zones 511) more than catmint. Furthermore, it won’t be forgotten because to its substantial size, which is 3 feet tall and 5 feet wide even when it’s not in bloom, which is virtually never. Over time, “Blue Dragon” grows into a sizable clump, but so yet it hasn’t been a nuisance. For little gardens, it’s generally not the best option to be safe. Even though it is only advertised as being cold hardy to Zone 6, we have lost a few plants over the course of two winters.
2. Weeks before most other catmints, the vivid lavender-blue flowers of ‘Early Bird’ (N. ‘Early Bird’) begin to bloom. Although I believe the flowers will generally bloom later in the month, in 2012, after a particularly mild winter in the Midwest, they burst into bloom in the first week of April. Only a few blooms are open at any given time, therefore the majority of the floral show is made up of the vibrant calyces. Last year, “Early Bird” was in bloom for about seven months, and throughout that time, the plants maintained their orderly routines. Early Bird is a particularly good ground cover due to its low, spreading nature (15 inches tall and 60 inches broad). It always reminded me of Tweety Bird and Sylvester the Cat that we planted the plants “Early Bird” and “Meow” next to each other.
3. “Lemon Pledge” catnip (N. cataria* “Lemon Pledge”) has only been around for one season, so it’s too new to receive a full endorsement, but it’s off to a good start. Let’s start by stating the obvious: The delicate gray-green leaves have a lemony scent that is reminiscent of canned goods. I couldn’t help but rub the plant’s leaves every time I passed it to let the delicious lemon aroma out. The first year, there weren’t many lavender-blue flowers, but the low, mounded habit was lovely throughout summer. Final dimensions of “Lemon Pledge” are anticipated to be between 12 and 16 inches tall and 16 inches broad. Even though it has a distinctive scent, this is still catnip, so don’t be shocked if it draws cats from the neighborhood.
4. The lack of cat-themed Nepeta cultivar names has always astonished me.
I prefer Kit Kat candy bars, but I’m getting off topic. I like “Cool Cat” and “Kit Cat” in particular. So when ‘Meow’ (N. ‘Meow’) made its appearance, I was pleased that a great plant bore its clever name. From spring until fall, “Meow” is covered in a profusion of blooms in substantial clusters. A lovely floral show is produced by the light purple blossoms that turn white as they age. When compared to other catmints, the plant’s crowns start to open around mid-spring. For the remainder of the season, the broad-spreading plants (26 inches tall and 50 inches wide) stay full and lovely.
5. From midspring to midfall, Little Trudy (N. ‘Psfike’) bursts into bloom with a profusion of lovely lavender blooms. The low, compact habit was slightly larger than expected (12 inches tall and 30 inches wide), but plenty of moisture in our trial allowed the plants to grow taller than they would have on drier areas. Although the sage green leaves are lovely all year long, in the middle of summer the habit can appear a little ragged. To revitalize the plants for a fantastic late-season floral display, I advise trimming back the stems in the middle of the season.
The manager of plant evaluations at the Chicago Botanic Garden in Glencoe, Illinois, is Richard Hawke.
Should catmint be trimmed back?
Once grown, catmint grows quickly and needs minimal maintenance. Although flowers are generated over a lengthy period of time, it’s a good idea to remove them after blooming to maintain the plant tidy and to promote the development of more. Before new growth arises in the spring, trim back the dead stems once the growth has died back in the late autumn. Delay pruning until early spring if at all feasible because dead leaves are ladybirds’ preferred site to hibernate. Every few years, catmint plants should be divided since huge, crowded clusters cause flowering to drop.
How to propagate catmint
Catmint can be divided once plants are several years old. The plant should be dug up in the fall or the first few weeks of spring. The clump should be divided into parts, each with a good number of roots and shoot buds, and then replanted in soil that has been improved with well-rotted compost or a soil conditioner. Water thoroughly to help the dirt surrounding the roots settle.
Growing catmint: problem solving
Given the proper growing circumstances, catmint is typically trouble-free, although plants rarely grow well in heavy, poorly drained soil or in shade. Powdery mildew can appear as a white coating on the leaves and stems during exceptionally dry summers. Cut off unhealthy shoots, collect, and discard impacted leaves.
How can catmint remain in flower throughout the summer?
- ‘Walker’s Low’ plants are 30 inches tall and 36 inches wide, with lavender-blue flowers. As a side note, the name is not short because it derives from an Irish garden. It is actually almost as tall as the “Six Hills Giant.” Walker’s Low was chosen by the Perennial Plant Association as their Perennial of the Year for 2007.
Don’t restrict yourself to just these four options if you feel driven to hunt for catmint in your neighborhood garden centers. Numerous other top-notch cultivars are also readily available, including “Dropmore,” “Blue Wonder,” and “Junior Walker,” a scaled-down variety of “Walker’s Low” that stands 16 inches tall.
- Catmint tends to grow wider than tall, so give it plenty of room.
- Even though catmint prefers direct sunlight, it can also tolerate some afternoon shade.
- Water new plants or transplants until they can survive on their own. Following that, established plants can withstand heat and drought.
- Never fertilize it again. Catmint prefers well-drained, moderately fertile soil. In fact, a plant may flop over or split in half if the soil is too rich. In that case, trim the plant back to make it look neat. Compost added in the spring or fall will provide the plant the nutrients it needs to thrive.
- After the first blooming flush of the plants has finished, shear them back by a third or more. The plants will be more orderly, their size will be limited, and this will encourage a second rush of blossoms later in the summer. The plant will still bloom often and maintain its lovely appearance during the stifling summer months even without being sheared.
- Over the winter, keep any dead foliage in place to help protect the crown. Wait till the beginning of spring to trim it.
- Divide catmint every three to four years, preferably in the spring or early fall, to maintain it healthy. During the first growing season, until the plants take root, keep it well-watered.
- Catmint varieties can grow to be quite huge. Pinch the plant back in the spring after it has grown a few inches tall to encourage a bushier growth habit if you wish to limit the plant’s total size.
- Cut a vertical chunk off of an established clump of catmint in the spring to reproduce it. Make sure the division has a strong root system and a number of new shoots. Till the plant takes root, keep it well-watered.
- Cuttings can also be used to spread catmint. Before flower buds grow in the spring, clip healthy shoots at a length of three inches. The cuttings should be placed in a moist medium, such as sand or a peat-perlite mixture. Within two to three weeks, they should start to root.
- Catmint is typically unaffected by either pests or illnesses. The only issue that can occasionally arise is leaf spot. There is no consensus that the severity of this fungus illness justifies control measures.
- Experience has taught me that some cats are drawn to catmint. If you’re worried about this, cover newly planted or transplanted catmint with chicken wire to stop your cat from consuming it or rolling about in it.
- This plant attracts butterflies and bees like crazy. Additionally, hummingbirds adore it.
- You’ll adore this plant if your garden is plagued by four-legged animals other than cats. Deer, voles, and rabbits are deterred by the foliage’s minty aroma. THIS is a plant that pays for itself, at last!