Dianthus: Plant Care and Collection of Varieties
There are numerous types of dianthus, so there’s one for almost any garden situation. Many types have flowers with a fragrant, spicy scent and notched petals. Common dianthus include Sweet William, pinks, and carnations.
Most dianthus have pink, red, or white flowers with notched petals. Sweet Williams are biennial or short-lived perennials covered with bicolor flowers in late spring. Pinks are low-growing dianthus suitable for rock gardens. Carnations are taller and good for bouquets but tend to be less hardy than other dianthus.
Special features of dianthus
Good for cut flowers
Choosing a site to grow dianthus
Select a site with full sun and well-drained soil, preferably with neutral to alkaline soil pH. Dianthus won’t tolerate wet soils, especially in winter.
Plant in spring or fall, spacing plants 6 to 12 inches apart, depending on the type. Prepare the garden bed by using a garden fork or tiller to loosen soil to a depth of 12 to 15 inches, then mix in a 2- to 4-inch layer of compost. Dig a hole twice the diameter of the plant’s container. Carefully remove the plant from its pot and place it in the hole so the top of the root ball is level with the soil surface. Carefully fill in around the root ball and firm the soil gently. Water thoroughly.
Apply a thin layer of compost each spring, followed by a 2-inch layer of mulch to retain moisture and control weeds. Water plants during the summer if rainfall is less than 1 inch per week. Stake tall varieties to keep them upright. Remove spent blooms on tall varieties, or shear back mounding plants after bloom to encourage rebloom. After the first killing frost, cut stems back to an inch or two above soil line. Divide plants every 3 to 4 years as new growth begins in the spring, lifting plants and dividing them into clumps.
Because woven cloth will fray when cut, special scissors with saw-toothed blades are used. The zig-zag cut limits the length of each thread, so fraying is avoided.
These “‘pinking scissors’” are not named for the color pink, but for the plant named pink, in the genus Dianthus. The ragged edges of the Dianthus petals indeed look as if they are cut by pinking shears.
Just as lilac became synonymous with a light purple color even though lilacs come in colors such as white or deep red, the pale red color known as pink may have come from one of the garden pinks’ most familiar colors.
The Garden Pinks or Dianthus genus includes annuals, biennials and perennials such as carnations (Dianthus caryophyllus) and Sweet William (Dianthus barbatus). Most are low, growing only 10 to 20 inches tall, though some carnations can reach three feet tall.
Pinks (Dianthus plumarius) multiply easily and are deer resistant. The fragrant blossoms come in many colors and make excellent cut flowers. For earliest blooms start Pinks (Dianthus) seeds indoors six to eight weeks before your last frost. When started indoors, they will usually bloom the first year.
You can also sow Pinks seeds directly in the garden once the ground has warmed up and all danger of frost has passed. When planted directly in the garden, Pinks probably will not flower until the following year. Plant the seeds one-eighth-inch deep in light, well-drained soil in full sun. They do best in rich soil that is slightly alkaline with pH 6.75. If your soil pH is below 7.0, add crushed dolomitic limestone. If your soil is too acidic, add wood ashes to lower the pH.
You can also propagate Pinks by taking cuttings or by dividing existing clumps of plants.
Take softwood tip cuttings in the spring or in early summer. Coat the cuttings with rooting hormone and plant in flats or pots. Keep moist, but not soggy, and your plants should be fully rooted and hardy enough to set out into the garden by fall.
Older clumps of Pinks can be divided and replanted. Dividing old clumps rejuvenates the existing plants. It’s easy to divide them in early spring just as they begin to sprout. Simply dig the entire clump up, roots and all, and gently pull it apart with your hands. If the clumps are too big or strong, use two gardening forks, cut into the center of the clump then slowly pry the plant apart. Each piece should have roots and be ready to be immediately replanted. It is a good idea to divide your Pinks every three to four years. Unless it is very dry, watering once a week is fine.
Pinks grow from a crown or leaves at the top of the root structure, so to prevent rot never bury any part of the stems or crown, and do not mulch them.
To keep blooms coming all season remove all faded flowers as they die. Because pinks often reseed themselves, you can let some of the flowers go to seed and increase next year’s blooms.
After your first killing frost in autumn, cut the plants down to just an inch or two above the soil line. Pinks do well in containers, in the front of mixed borders, planted as a cutting garden, or part of cottage gardens.
Use the nutmeg scented blossoms steeped in wine, coated with sugar as cake decorations, or tossed in salads. Pinks are one of the secret ingredients in the French liqueur Chartreuse.
Pink is a flower, a color and a mood, so much so that a band once known as Tea Set would go on to sell over 250 million records and influence David Bowie, Queen, Phish, Radiohead, and Yes, but only after the band changed their name.
They combined the names of blues singers Pink Anderson and Floyd Council to become Pink Floyd. And that made gardeners who are music lovers tickled pink.
With winter behind us, we welcome a new season with one of our favorite spring-blooming perennials, Dianthus! These re-blooming flowers give us that color we’ve been waiting for. Not only are they beautiful, they are also very easy to grow. The most difficult part of growing dianthus is choosing which types you want to plant. Depending on the variety, blooms begin in early spring and continue all the way until frost. Dianthus blooms may be single or double (think little carnations), and tend to be white, pink, red, rose, or lavender – available in nearly all shades except true blue. Dianthus plants range from tiny creeping groundcovers to 30-inch-tall cut flowers, which are a favorite with florists.
Dianthus are drought-tolerant plants ideal for sunny spots at the edge of a flower bed or a path. Plant them early in the season, so they can become well established before hot weather sets in. These petite flowers sparkle in borders, beds, window boxes and containers. They flourish in the cool temperatures in spring and fall and prefer a full-sun location and well-drained soil, preferably with neutral to alkaline soil ph. Dianthus is also deer resistant. If you’re looking to add a blooming spring addition to your garden, look no further than dianthus. Before you know it, you will find your garden filled with the vibrant colors and distinctive fragrance. Here are a few of our favorites:
Dianthus, Pink Pompom – delightful rose-pink double flowers provide a bright burst of color in early spring, appearing continuously until autumn. The tidy mounding habit is practically maintenance-free. Pompom is perfect in landscape borders, rock gardens, containers and as a long-lasting cut flower. May remain evergreen in warmer winter regions. Prefers partial to full sun.
Dianthus, Double Bubble – features fully double flowers and simple, pure pink color. A profuse bloomer, ‘Double Bubble’ will be completely covered in blooms in early summer and then again in early fall. Foliage tends to be steely blue-green and finely textured and takes center stage when the plant is not in bloom. Plant in mass or in borders and containers. Double Bubble is deer resistant, low maintenance, drought tolerant and fragrant. This dianthus truly has it all!
Dianthus, Early Bird Chili – begins its show just as the weather starts to warm and keeps on blooming through autumn. Blooms stand tall above grassy, blue-green foliage with sturdy stems. Bold, coral double-blossoms sparkle in borders, beds, patio pots and window boxes. Its fragrant blooms are also perfect for cut flower arrangements. Early Bird prefers full sun and well-drained soil.
Photos provided by Centerton Nursery, Monrovia and Plant Haven International, Inc.
Dianthus gratianopolitanus ‘Firewitch’
By Paul Pilon
By Paul Pilon
Dianthus gratianopolitanus — commonly called cheddar pinks — is one of the most widely grown and marketed dianthus species and is well suited for landscapes across much of the country. Based on its desirable characteristics and garden performance, ‘Firewitch’ is commonly produced by perennial growers and widely utilized in American gardens. This popularity coupled with its many desirable attributes caused the Perennial Plant Association to name Dianthus gratianopolitanus ‘Firewitch’ the 2006 Plant of the Year.
‘Firewitch’ bears numerous solid bright-magenta-pink flowers with serrated edges. The 1-inch flowers are held above blue-green foliage. Plants form small, compact mounds measuring about 7 inches tall by 12 inches wide and remain evergreen throughout the year.
‘Firewitch’ performs well throughout USDA Hardiness Zones 3-9 and AHS Heat Zones 8-1. It prefers to be grown in full sun, although locations receiving partial sun are often acceptable. Dianthus gratianopolitanus bloom prolifically in early summer and will continue to bloom sporadically throughout the season. Deadheading, or removing spent blooms, is highly recommended to promote a reflush of flowers.
‘Firewitch’ is most commonly vegetatively propagated by tip cuttings. Propagators have the most success when propagating during the early spring or late summer when the plants are not flowering and are growing vegetatively. Tip cuttings should measure approximately 2 inches and contain several nodes. The well-drained rooting media should be moistened prior to sticking. The base of the cuttings can be dipped into a rooting hormone, such as a solution of indolebutyric acid (IBA) at rates between 750 and 1,000 ppm prior to sticking.
Cuttings should be placed under low misting regimes for about the first two weeks of propagation. When possible, it is usually best to propagate under high humidity levels (90-percent relative humidity) with minimal misting. Prolonged exposure to mist may cause the leaves to rot during propagation. The misting can gradually be reduced as the cuttings callus and start to form roots. Plants will usually form roots within 3-4 weeks of sticking as long as soil temperatures range from 68 to 73¼ F. A liner takes approximately 4-6 weeks to become fully rooted and ready for transplant. Plugs acquired from propagators range in size from 128 cells up to 3-inch liners.
For container production, ‘Firewitch’ is suitable for 1-qt. to 1-gal. containers. Most growers receive starting materials of Dianthus gratianopolitanus as finished plug liners. “Firewitch’ can be started using bareroot materials; however, the quality of the finished product is often greatly reduced. Spring-planted dianthus often remain small and bloom before the plant has reached a marketable size. For spring sales, it is highly beneficial to plant plugs during the late summer of the previous year, allowing them to bulk up prior to over-wintering.
Dianthus performs best when it is grown in a well-drained, porous growing medium with a slightly acidic pH of 6.0-6.5. The plugs should be planted so the original soil line of the plug is even with the surface of the growing medium of the new container. Planting the crown too deeply will lead to crop variability and losses from crown rots. After planting, I recommend growers drench with a broad-spectrum fungicide such as Banrot (The Scotts Company LLC) or the combination of Subdue MAXX (Syngenta Professional Products) and Medallion (Syngenta Professional Products).
‘Firewitch’ requires an average amount of irrigation as it does not tolerate overly wet or dry conditions. When moist or wet conditions occur, plants are very susceptible to root rots. When irrigation is necessary, growers should water plants thoroughly, and then allow the soil to dry slightly between irrigations.
Dianthus is a moderate feeder; fertility can be delivered using water-soluble or controlled-release fertilizers. Growers using water-soluble fertilizers should either feed with a constant liquid fertilization program using rates of 50-75 ppm nitrogen with every irrigation or apply 100-150 ppm of nitrogen as needed. Growers commonly apply time-release fertilizers as a top-dress onto the media surface using the medium rate, or fertilizers are incorporated into the growing medium prior to planting at a rate equivalent to 1 lb. of nitrogen per yard of growing medium.
Best quality is achieved when plants are grown in full sun or greenhouses with high light intensities; 3,000-5,000 foot-candles is sufficient. When produced under lower light levels, the stems will become leggy, and overall plant quality will be reduced. During the winter months, crop quality can be greatly improved when 400-500 foot-candles of supplemental lighting is provided.
Due to its naturally small growth habit, controlling plant height with chemical growth regulators should not be necessary. However, during the winter months and periods of low light levels or when grown at high plant densities, excessive plant stretching might occur, especially as ‘Firewitch’ begins to develop flowers. During these times, ‘Firewitch’ may require some type of height-management strategy. The height of dianthus can often be effectively controlled by providing adequate spacing between plants. Dianthus gratianopolitanus can be grown at high plant densities throughout most of the production cycle. As flower buds develop and stems begin to elongate, typically the last few weeks of production, it is beneficial to space pots slightly further apart.
Insects And Diseases
Aphids, caterpillars and thrips occasionally become problematic. The primary insect observed feeding on dianthus is aphids. Although dianthus is an acceptable food source for aphids, it does not seem to be their main preference. With aphids and other insect pests only occurring occasionally, growers do not have to implement preventative programs but can detect their presence through weekly scouting activities to determine if control measures are necessary.
Dianthus can generally be grown free of plant pathogens. The primary diseases growers should watch for are Pythium and Rhizoctonia crown and root rots. Plants are most susceptible to these diseases when they are grown under cool and wet conditions, such as going into or coming out of winter dormancy. Growers should also be on the lookout for various leaf spots caused by the fungal pathogens Alternaria, Cladosporium and Phyllosticta.
As with many perennials, the occurrence of plant diseases on dianthus can be negated or greatly reduced when the proper cultural practices are followed. To control these diseases, it is best to manage the environment by providing proper plant spacing and adequate air movement and controlling the humidity. Growers should carefully watch the moisture levels during adverse times of the year and avoid overwatering their plants. Routine scouting is useful and recommended to detect plant diseases early, allowing the appropriate control strategies to be implemented before significant crop injury or mortality occurs.
When producing blooming plants is the goal, a few requirements should be met to achieve consistent, high-quality flowering plants. It is recommended to begin the forcing process using plant materials that have been “bulked up” to nearly fill out the container they are being produced in.
‘Firewitch’ has an obligate cold requirement for flowering. It will flower sporadically and have low bud counts when vernalization is omitted. It is recommended to cool large containers of ‘Firewitch’ that have been bulked up for 6-9 weeks at 35-44¡ F. Plugs for spring transplanting into small containers can successfully be vernalized prior to planting as well.
After the cold requirement is achieved, ‘Firewitch’ can be grown at any day length, as they are day-neutral plants. The length of the photoperiod does not have any effect on the number of blooms produced. Dianthus are considered long-day-beneficial plants, as they flower faster when grown under higher light intensities and/or long-day conditions.
The time to bloom after vernalization is a function of light intensity, photoperiod and temperature. ‘Firewitch’ will reach full bloom in approximately 7-8 weeks when plants have been grown at temperatures averaging 65¼ F. Producing them at cooler temperatures increases time to flower but will improve the overall quality characteristics of the plant, such as color intensity of the foliage and flowers. To achieve the highest plant quality, I recommend growers produce dianthus using cool temperatures, such as 60-65¼ F.
‘Firewitch’ liners are widely available through numerous perennial propagators and plant brokers. Finished containers can be purchased from many reputable growers throughout the country.
Firewitch Dianthus in bloom
Firewitch Dianthus in bloom
(Photo courtesy of NetPS Plant Finder)
Firewitch Dianthus flowers
Firewitch Dianthus flowers
(Photo courtesy of NetPS Plant Finder)
Height: 8 inches
Spacing: 8 inches
Hardiness Zone: 4a
Other Names: Cheddar Pinks, Clove Pinks
2006 Perennial of the Year: slightly fringed magenta flowers on dense blue-green foliage; Deadhead for summer long beauty
Firewitch Dianthus has masses of beautiful fragrant fuchsia frilly flowers with white eyes at the ends of the stems from late spring to mid summer, which are most effective when planted in groupings. The flowers are excellent for cutting. Its attractive grassy leaves remain silvery blue in color throughout the year. The fruit is not ornamentally significant.
Firewitch Dianthus is an herbaceous evergreen perennial with a mounded form. It brings an extremely fine and delicate texture to the garden composition and should be used to full effect.
This plant will require occasional maintenance and upkeep, and is best cleaned up in early spring before it resumes active growth for the season. It is a good choice for attracting bees and butterflies to your yard, but is not particularly attractive to deer who tend to leave it alone in favor of tastier treats. It has no significant negative characteristics.
Firewitch Dianthus is recommended for the following landscape applications;
- Mass Planting
- Rock/Alpine Gardens
- Border Edging
- General Garden Use
- Container Planting
Planting & Growing
Firewitch Dianthus will grow to be about 8 inches tall at maturity, with a spread of 12 inches. When grown in masses or used as a bedding plant, individual plants should be spaced approximately 8 inches apart. Its foliage tends to remain low and dense right to the ground. It grows at a medium rate, and under ideal conditions can be expected to live for approximately 5 years.
This plant should only be grown in full sunlight. It prefers to grow in average to moist conditions, and shouldn’t be allowed to dry out. It is not particular as to soil type or pH. It is highly tolerant of urban pollution and will even thrive in inner city environments. This is a selected variety of a species not originally from North America. It can be propagated by cuttings; however, as a cultivated variety, be aware that it may be subject to certain restrictions or prohibitions on propagation.
Firewitch Dianthus is a fine choice for the garden, but it is also a good selection for planting in outdoor pots and containers. It is often used as a ‘filler’ in the ‘spiller-thriller-filler’ container combination, providing a mass of flowers and foliage against which the thriller plants stand out. Note that when growing plants in outdoor containers and baskets, they may require more frequent waterings than they would in the yard or garden. Be aware that in our climate, most plants cannot be expected to survive the winter if left in containers outdoors, and this plant is no exception. Contact our store for more information on how to protect it over the winter months.
Gertens Sizes and Prices
#1 container – $7.99
* Sizes and availability are subject to change. Please check with the store for specific details.
Dianthus ‘Firewitch’ is the ultimate in fragrance! Durable, hardy, easy to grow ground cover deserves a spot in your perennial garden.
In late spring, hundreds of shocking magenta pink flowers contrast beautifully against evergreen silvery blue foliage. Flowers will often repeat again later in the summer when the weather turns cool.
This sun plant is a fine addition for your cut flower garden. Highly fragrant blooms last for days all the while adding a natural fragrance to almost any room of your home. You won’t believe the powerful, delightful fragrance that comes from these little flowers.
Since the foliage is evergreen, this is an excellent ground cover for the sun perennial garden and a perfect edging plant in front of your perennial border.
We love to pair this fragrant beauty with other evergreen ground covers like low growing sedums. Use as a foreground planting to daylilies, coneflowers, or Knock Out Roses.
Special features: Attracts butterflies, Cold hardy, Cut flower, Deer resistant, Disease resistant, Drought tolerant, Easy dare, Evergreen, Fast growing, Fragrance, Heat tolerant, Pest resistant,