Pinks: Petite and Prolific

A perennial border pink adds a profusion of color in late spring.

I’ve always been taken with the many romantic names for members of the genus Dianthus. Evocative monikers include maiden pinks, cottage pinks, sweet Williams, cheddar pinks, and Scotch pinks. Trying to sort them out, though, is another story. 

Having grown many different plants from this genus in my garden in Kitchener, Ontario, I’ve started to ignore the common names—as much as I like them—and instead think about them from a purely practical gardening point of view. For me, a simple key to choosing individual pinks is to know which garden use suits them best.

Rock garden dwellers invite up-close viewing

Many of the pinks suited to rock gardens are so tiny they would get lost in most other gardens. An excellent rock-garden choice is cheddar pink (D. gratianopolitanus and cultivars., USDA Hardiness Zones 4 to 9), which produces little tufts of mat-forming blue-gray leaves from 3 to 8 inches high and sports pale-pink flowers in early summer. 

Alpine pinks (D. alpinus and cultivars, Zones 3 to 7) produce clusters of beautiful, serrated, single blooms in deep pink to dark crimson that sit just off the ground, staring up at a viewer. Unfortunately, these summer bloomers are among the few Dianthus plants that are not fragrant, but don’t let that stop you from growing them.

Rock garden pinks are often grown from seed because they are not widely available as plants. If you are lucky enough to obtain seeds, perhaps from a rock garden club or a specialty nursery, barely cover them in a well-drained growing medium, keep them at 60 to 70F, and they should sprout in two to three weeks.

Dense clumps of maiden pinks form a low-growing swath of magenta.

D. alpinus

D. gratianopolitanus (cheddar pink)

Low-growing pinks need a front-of-the-border spot

Popular maiden pinks (D. deltoides and cultivars, Zones 3 to 9) are low-growing but rather too prolific and exuberant for most rock gardens. Instead, use these to create a low-lying cloud of color at the front of a border or on a gentle slope. Having been hybridized for centuries, they come in many attractive colors. Most are a single color, usually white, red, or dark pink, but some are bicolored. One of my favorites is ‘Arctic Fire’, which is white with a cherry-red eye.

Since they germinate easily, maiden pinks are best grown from seed. Indoors, start them a few weeks before the last frost. Outdoors, sow them in early spring. Maiden pinks are perennial but tend to be short-lived, especially in less-than-ideal conditions. However, in full sun and well-drained soil, they will self-sow and go on to produce larger clumps each year. In such conditions, they become low-maintenance plants that just need to be kept in check by dividing them.

Another popular pink ideal for the front of a border is D. gratianopolitanus ‘Bath’s Pink’. This cultivar is more substantial and floriferous than the species, which is best suited to rock gardens.

D. deltoides (maiden pink)

D. gratianopolitanus ‘Bath’s Pink’

D. Deltoides ‘Arctic Fire’ (maiden pink)

Annual pinks (D. chinensis cultivars) also tend to be rather short—up to about 6 inches—so they too work well in the front of a border. Also known as Chinese pinks, they are easy to grow from seed and should be started indoors 8 to 10 weeks before the last frost. That’s a long time to carry over a plant if, like me, you don’t have a greenhouse. That’s why I usually just buy them as plants at a local nursery.

Usually deeply fringed, they are unfortunately not perfumed. Like other annuals, their attraction is that they bloom longer than the perennial and biennial pinks. The flowers are usually single and rather large, with beautiful markings. In recent years, the most popular varieties have been ‘Strawberry Parfait’ and ‘Raspberry Parfait’, showy Fleuroselect medal winners. I also like ‘Ideal Crimson’. It has smaller flowers and rich bright-red blooms that appeal to humans and hummingbirds alike.

One low-growing pink to avoid is the aggressive Dept­­ford pink (D. armeria). I still find an occasional seed­ling of this biennial in my garden, even though I’ve carefully removed every one I’ve found for the last five years.

D. chinensis 'Ideal Crimson' (annual or Chinese pink)

Border pinks bloom profusely and smell good

Many Dianthus cultivars are commonly called border pinks, and for good reason: That’s where they look best. Whereas maiden pinks make a low carpet of color, border pinks produce large, high clumps that disappear under a profusion of blooms in late spring. In a well-drained, sunny spot, they are long-lived, but unless they are kept on a lean diet, they can be floppy and need staking.

This group of perennials is often subdivided into old-fashioned border pinks, which were introduced before 1920, and modern border pinks. The old-fashioned pinks are mostly tuft-forming and grow to about 18 inches high. Modern border pinks are often hybrids of D. plumarius and D. caryophyllus and grow from 6 to 24 inches high. Since the clumps tend to be manageable, the plants do not usually need to be divided as they mature. However, it’s easy to divide them if you would like to increase your stock, since border pinks do not generally self-sow.

Border pinks are much more fragrant than maiden pinks; in fact, many border pinks are among the most strongly perfumed of the genus. For many years, I grew ‘Mrs. Sinkins’ (Zones 5 to 9), a double, perfectly white Victorian variety that has a particularly strong, wonderful perfume. However, with blooms almost as big as a florist carnation, it had to be staked. There is also a pink variety, ‘Pink Mrs. Sinkins’.

Many border pinks are widely available, so if you need just a few plants, it’s often most practical to buy them “ready-made.” A popular variety called ‘Spring Beauty’ (Zones 3 to 9)  is available as both plants and seed. Seeds are easy to start following the instructions on the packet. In some cases, such as with a hybrid mix, you get some single and some double in varying shades of pink, white, and red.

D. ‘Spring Beauty’ (border pink)

D. ‘Mrs. Sinkins’ (border pink)

The biennial sweet Williams (D. barbatus and cultivars, Zones 3 to 9) also make good border plants. These charmers have been popular for centuries. I live in a place where some homesteads have long been reclaimed by forest. You can guess where the houses once stood by the patches of weak-looking sweet Williams that still survive among the trees. This is another type of Dianthus that looks lovely planted in drifts.

Single- or double-flowered, sweet Williams vary in height from about 6 to 24 inches. According to 17th-century herbalist John Gerard, their best use is “to decke up the bosomes of the beautiful.” But if all you have in mind is trying to recreate a Victorian garden, choose a tall, double-flowering variety. Sweet Williams can be bought as plants, but in my experience they look better grown from seed. Having been “born” and acclimatized in your own garden, they look more established come blooming time.

Sweet Williams can be seeded one year to bloom the next. To have some every year, you will need to seed them every spring directly in the garden. Some gardeners think they have a perennial variety, but it is the plant self-sowing each year. Even if yours does so, it might be a good idea to buy new seeds every now and then, since a seed mix will likely revert after a few years from a wonderful blend of colors to a basic pink or dark red. The size of the blooms also will decrease over time. In addition to the wonderful mixes available, sweet William seeds are also available in single colors.

Last spring, in a crunch, I raided a prolific drift of my sweet Williams. A day before a tour of my garden, I transferred a few clumps of a mauve-flecked white variety into attractive pots where they brightened up a dull corner for the big day and a few weeks thereafter. Then they produced a lot of seed, which I sowed right away. In the fall, I had some nice clumps ready to bloom the following spring.

D. barbatus (sweet William)

D. barbatus (sweet William)

Pinks are not fussy, but they do hate being too wet

D. amurensis ‘Siberian Blue’

Although the Dianthus species and cultivars grown in gardens are commonly called “pinks,” the palette of blooms of the genus Dianthus ranges from pure white to dark raspberry-red. D. amurensis ‘Siberian Blue’ (Zones 3 to 7) is an attractive lilac-tinted pink that only hints at being blue. The one real exception is D. knappii (Zones 3 to 9), a yellow curiosity. I find it too leggy and weak-kneed to be useful in my garden.

ll Dianthus plants are sun lovers and prefer average, well-drained soil. They appreciate a bit of humus in the top soil layer, but they will not survive long in a damp, highly fertile muck. Do not use mulch around pinks because their crowns tend to rot beneath it.

Grown in conditions they like, pinks are usually disease-free. The major pest problem is mice and voles, which often nibble at pinks under the snow in winter. One way to avert this fate is to put mice bait under a covered trap with a small opening and place the trap in a bed near dormant pinks.

Pinks generally bloom profusely. In early summer, it’s often hard to see the foliage because the plant is completely covered with flowers. Their floral extravagance tends to exhaust Dianthus plants, making them short-lived; cutting them back can extend their life span. Perennial pinks should be trimmed by as much as half the foliage height after they’ve finished blooming. Immediately after trimming, they won’t look great but will soon send forth a new clump of fresh foliage that might rebloom later in the season.

Whichever types of Dianthus you choose to grow, I can assure you that you will find them as charming as their common names suggest.