Skip to main content

Summertime planting: Caring for your gorgeous, spicy-smelling dianthus

A complete summer care guide for dianthus

A cluster of small dianthus flowers
matthiasboeckel/Pixabay / Pixabay

Dianthus, also called pinks, are beautiful flowers with unique shapes and scents. Although many dianthus flowers are the color pink, their name actually comes from the shape of their petals. People long ago thought the petals looked like they had been cut with pinking shears, which leave a zigzag pattern. When planning your summer garden, whether indoors or out, dianthus should be at the top of your list. These flowers are easy to grow, come in many fun varieties, and will fill your garden or home with color. Here’s everything you need to know about dianthus care in summer.

Pink dianthus flowers with white spots
sylviahsc / Pixabay

Dianthus varieties

Dianthus is a genus of plants that contains a multitude of flower species, which come in an array of colors and sizes. Some types of dianthus may already be familiar to you. For example, carnations are a type of dianthus, Dianthus caryophyllus to be specific. Sweet William (Dianthus barbatus) is another dianthus species commonly found in gardens.

Recommended Videos

One type of dianthus you might not know as well is Dianthus armeria, also known as Deptford pink or grass pink. This dianthus species has lovely flowers in various shades of pink, often with some light speckling. If you want something a little more unusual, then how about Dianthus superbus? As the name suggests, it’s quite superb. This dianthus species has wide petals with long fringes, making it look a bit like a jellyfish or star-nosed mole.

Red and white carnations
matthiasboeckel / Pixabay

How and when to plant dianthus

Most dianthus species should be planted in the spring, although you can plant some perennial types in the fall. You can grow dianthus from seeds or nursery starts. Seeds can be planted at any time after the last frost of winter, but you can start them indoors six to eight weeks before the last frost.

With nursery starts, you can typically plant them as soon as they begin arriving in nurseries. After all, chances of frost have passed is the best time to plant them. You can plant mature versions at any time, but these are the best option for summer planting.

Whether you’re growing seeds or starts, plant your dianthus in full sun. They can tolerate some shade, with a few varieties being more tolerant than others. However, planting dianthus in the shade results in fewer flowers and a generally weaker plant. They are also more vulnerable to fungal infections.

Space your dianthus plants 6 to 12 inches apart, depending on the mature size of the dianthus you’re growing. Adding compost to the soil before planting can help improve both the nutrient balance and drainage of the soil. If you’re planting a nursery start or a mature plant, make sure the hole you dig is twice as wide as the root ball. Set the plant in the center and fill the soil in around it.

Dark purple and white dianthus flowers
matthiasboeckel/Pixabay

Dianthus care

In general, dianthus are low-maintenance plants, although there is some deviation from species to species. They are drought-tolerant plants, typically only needing water once a week. Some species may need even less. Dianthus care in summer mostly consists of deadheading any spent blooms and giving them extra water during heat waves or droughts. Water them beneath their leaves rather than from overhead, as overhead watering can cause or exacerbate mildew or rot.

Taller dianthus plants may need staking, as their stems tend to be thin and prone to flopping or breaking. In windy regions, providing a windbreak can also keep your tall dianthus plants upright. Mulch can be useful for keeping weeds at bay and improving the soil’s water retention. Bark and stone are good choices for dianthus plants. Keep the mulch a couple of inches away from the stems of the dianthus to maintain good airflow and prevent possible abrasions.

A cluster of magenta and white dianthus flowers
manfredrichter/Pixabay

Common problems and solutions

Dianthus plants are resistant to many pests. In part, this is because they’re mildly toxic to animals. This typically keeps deer at bay, although some small insects will still eat them. However, it does pose a slight risk to any pets you have. Although it is unlikely to cause serious harm to your pets unless they ingest a large amount, it can cause an upset stomach. The sap from dianthus plants can also be a mild skin irritant.

The most common dianthus problems are due to overwatering and/or poor drainage. When left in wet soil for too long, it is prone to root rot, crown rot, and powdery mildew. Unfortunately, plants affected by crown rot often can’t be saved and need to be removed from the garden to prevent spread.

Mild cases of powdery mildew can be treated with fungicides. Mild cases of root rot may be treated by removing the plant, trimming the diseased roots, and replanting it in clean, dry soil. However, severe cases of both are often best treated by simply removing the infected plant.

Pink dianthus flowers
manseok_kim/Pixabay / Pixabay

Should you deadhead your dianthus?

Yes, you should deadhead your dianthus, especially during summer. While leaving spent blooms on your dianthus plant won’t harm your plant, deadheading offers a variety of benefits. It encourages your dianthus to keep blooming, keeps your garden looking fresh and neat, and stops your dianthus from reseeding. If you plan on continuing to grow dianthus in your garden and want your plants to reseed, then we suggest deadheading most of your dianthus blooms and only leaving a few to put out seeds. This helps control the amount of dianthus seeds going into your garden as well as gives you the additional blooms provided by deadheading — it’s a win-win.

Dianthus is a delightful and beautiful genus with gorgeous flowers. Whether you prefer the delicate Sweet William, the elegant carnations, or the unique Dianthus superbus, these flowers are a sight to behold in any garden. Take care not to overwater them, be sure they get plenty of sun, and keep them out of reach of any curious cats or dogs you may have. Your dianthus will reward you with tons of lovely flowers!

Topics
Cayla Leonard
Cayla Leonard is a writer from North Carolina who is passionate about plants.  She enjoys reading and writing fiction and…
Companion flowers for vegetables: What to plant in your garden
Add these flowers to your vegetable garden to help it thrive
A close-up of a marigold bloom

If you want fresh vegetables to enjoy at home, growing your own is one way to achieve that. There are many easy to grow vegetables, and it’s possible to have a thriving vegetable garden no matter your experience level. However, proper companion planting can be a huge help in the garden. Using a companion planting chart to choose which vegetables to plant next to each other is the first step, but the second is to choose the right companion flowers for vegetables. Here are a few of the best options for you to consider.
Bee balm

There are several functions that companion flowers for vegetables can serve. Bee balm is great for attracting pollinators. This is helpful for any garden, but especially for vegetable gardens with a lot of fruits like peppers, tomatoes, cucumbers, and eggplants. Pollinators are drawn to the bee balm, and then they visit your vegetable plants. More pollinated flowers means more delicious tomatoes to harvest.

Read more
5 gorgeous perennials that like full sun: Top picks
Add these perennials to your sunny garden
A field of lavender

A sunny flower garden full of vibrant, colorful flowers sounds like a dream, and many people take up gardening just to achieve it. While it isn’t difficult to grow a garden like that, the sun can sometimes get in the way. The intense afternoon sun can burn some plants, leaving unsightly brown marks on their leaves and wilting their flowers prematurely. Luckily, some simple planning can eliminate this problem! All you need to do is plant flowers that thrive in the bright sun, such as these five gorgeous perennials that like full sun.
Blazing star

Blazing star, or liatris, is a tall perennial native to the marshes and prairies of the U.S. It's known for its slender flower stalks lined with small purple flowers. These stalks can grow up to 6 feet tall. During late summer and autumn, when they’re in full bloom, blazing star flowers almost resemble large purple cat tails. Although they don’t look like it, these interesting flowers are actually a member of the aster family.

Read more
The beauty of heliotropes: A beginner’s care guide
How to grow heliotrope indoors and out
Purple heliotrope flowers growing outdoors

If you’re a fan of purple flowers, then you’re likely already familiar with the beautiful heliotrope plant. This tender perennial is known for deep purple flowers and an oddly delicious scent -- it’s sometimes called the cherry pie plant after the blend of fruity, almond-like, and vanilla-like scents it produces. If you want to add this plant to your home or garden but aren’t sure where to start, then we’re here to help. This guide to growing heliotrope for beginners will outline everything you need to know about basic heliotrope care.
Planting heliotrope

You can plant heliotropes any time after the last frost of the year or start them indoors at any time. If you’re starting your heliotrope plants indoors during winter, be sure to keep them warm and don’t leave them near any drafts or air vents. A grow light may also be helpful to ensure your heliotropes get plenty of sun.

Read more