How to Plant, Grow, and Care for Bachelor’s Buttons
Looking for easy flowers? Bachelor's buttons come in a range of shades in blue, pink, and purple! Lorin Nielsen explains these easy annuals and provides all the tips you need to grow them for a beautiful wild garden.

Contents
One of my favorite flowers, bachelor’s buttons, is sometimes called cornflowers. And from there, the color “cornflower blue” derives its name!
Also called basket flowers, blue bonnets, blue cap, and many other names, this popular plant is a hardy annual. It blooms in an array of color from early spring through the fall months. Leave some of the spent flowers on the plant, and it’ll happily reseed its bed and grow again next year.
But what are bachelor’s buttons, and are they all blue? Do they prefer sunlight or shade? How much water do they need? We’ll cover all this and more today as we explore the world of the bachelor’s buttons!
Plant Overview

Plant Type
Annual
Family
Asteraceae
Genus
Centaurea
Species
Centaurea cyanus
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Native Area
Southern Europe and Middle East
Exposure
Full sun
Height
40”
Watering Requirements
Low
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Pests & Diseases
Aphids, mealybugs, powdery mildew and rust
Maintenance
Low
Soil Type
Well-draining, rich loam
Hardiness Zone
2-11
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What are Bachelor’s Buttons?
Botanically, it’s called Centaurea cyanus and commonly called bachelor button, blue cornflower, or bachelor’s buttons. This name refers to old folklore. Young love-struck men would wear them on their lapels. If the early flowering bloom faded fast, it was thought the object of their desire didn’t love them.
Native Area

Bachelor’s button has a long list of names, including unusual ones like blue blob, corn bottle, gogglebuster, and hurt sickle. One name, cornflower, originated from the tendency of these plants to grow as native plants in European cornfields. It is also found naturally in areas of the Middle East.
While declining in its natural habitat, the growth of this plant worldwide has expanded via gardens designed for cut flowers. Many varieties are blue. However, bachelor’s buttons can be pink, purple, and white as well.
This annual’s self-sowing tendency has caused them to become listed on the USDA’s list of introduced, invasive, and noxious plants. North Carolina has become so plagued by it that selling its seeds or live plants is prohibited in that state! Try planting in a container if you live in this plant’s invasive area.
Characteristics

Grey-green or silvery-green slender foliage with long, lanceolate leaves forms the base upon which bright flowers form. It can reach up to three feet in height and can sprawl out one to two feet wide. The greyish or silvery tint is actually caused by fine white hairs on the leaves.
Their edible flowers can be used in salads as a touch of added color. Petals are often dried and added to loose tea blends for a pop of color. In addition, the flowers are a historical pigment or dye source for painting or dyeing fabric.
Planting

To plant bachelor’s buttons, choose a spot with full sun and well-draining soil. Loosen the soil to a depth of six to eight inches and mix in compost to enrich it. Sow the seeds directly outdoors after the last frost, spacing them six to eight inches apart.
Cover the seeds lightly with about a quarter of an inch of soil, and water gently to keep the soil evenly moist until germination, which usually takes seven to ten days. Once established, the plants require little care, though occasional watering during dry spells will help them thrive.
How to Grow
Of all the flowers you can grow, bachelor’s buttons will be some of the easiest to grow year after year. You can fine-tune care to gain perfect conditions, but they’ll grow well even in poor locations!
Light

Bachelor’s buttons prefer full sun but can tolerate partial shade. Give them at least six to eight hours of direct sunlight daily for optimal growth and abundant blooms. While it can tolerate partial shade, reduced sunlight may result in fewer flowers and leggier growth. They need lots of light to produce their array of flowers, so be sure to plant them in an area where they’ll receive ample daylight!
Water

Surprisingly drought-tolerant, bachelor’s buttons can tolerate everything but muddy conditions. These are not fussy plants on the whole. After all, they grow wild in many regions! Whenever possible, avoid watering these plants from overhead. Ensure that they don’t sit in areas that develop standing water.
They can live in humid environments, but adequate airflow is recommended to reduce the risk of fungal disease. Moisture on the leaves can promote the formation of mildew. Excessive water at the root zone can cause root rot. Do what you can to avoid these conditions!
Soil

In its natural environment, bachelor’s buttons grow in loamy, well-drained soil. They’re very tolerant of other soil types. If possible, avoid soil that becomes extremely wet, as that can endanger the plant’s health!
Also, they can be grown in neutral soils through soils with quite a bit of alkalinity. A pH range of 6.6 to 7.8 is favorable for these plants, although an optimal range would be best at around 6.9 to 7.4. This provides the little bit of alkalinity they like without going too far over.
Temperature

These plants are tough temperature-wise. Young seedlings can tolerate light freezes and often germinate in the late winter and early spring. Weaker plants will die back. Hardier plants continue to survive and flourish. They tolerate heat, but in the most extreme heat conditions, they may need extra attention to keep them healthy.
Fertilizer

Most soil types provide ample nutrition for your bachelor’s buttons plants. If you’d like to boost them, work in some compost or a balanced slow-release fertilizer before planting.
Every month or two, spread some compost around the base of your blue cornflower. This should provide lots of nutrition and guarantee you’ll have plenty of flowers throughout the year.
Maintenance

Bachelor’s buttons can become unruly if they’re not supported. Since these can reach three feet tall, they can become a weedy tangle of bent stems if you don’t offer an assist!
One of the simplest ways to support cornflowers is to place four short wooden stakes at the corners of your bed. Stretch a piece of chicken wire or nylon mesh between these stakes and use staples to anchor it in place.
As your seedling plants grow, they’ll stretch through the wire or mesh. This provides some low-level support against windy or rainy conditions. It also keeps small animals like rabbits away from the base of your plants.
If you choose to let them grow unsupported, too much wind can cause them to bend or lean. Trim off growth that gets in the way of pathways or other plants if you wish, or use them as cut flowers. Aesthetics define the pruning necessity here.
Deadheading your flowers is also a good choice. When you don’t deadhead spent flowers, they will self-seed the plot and spring right back up the next year! This also promotes more flowering.
Propagation

Seed is the easiest way to propagate these plants and the way that most people choose. You can sow seeds directly in the soil or start them in containers.
Once your soil’s prepared, mist it to dampen the surface and then tuck the seeds just beneath the surface. They will germinate in seven to fourteen days. Once germinated, you should thin them down to one plant every eight to twelve inches or so. I recommend twelve inches for extra growing space.
Your plants will fill in the space once they begin to really push up leaves and stems, and in time they’ll flower. These flowers can produce open-pollinated seeds for next year if you’d like!
To collect seeds from your bachelor’s buttons, wait until the flowers have faded naturally and fully dried. Cut the flower off its stalk, then break it up to reveal the seeds hiding within. The seeds are oblong in shape with a tuft of brownish hair at the end.
Allow your seeds to dry for seven to ten days in a cool, dry location, and then store them until the next planting season.
Repotting

Growing the bachelor’s buttons in pots is also optional; they don’t need repotting. As long as you begin with a pot that is about a foot wide, one plant will cheerfully grow in its available space until it dies back in the fall.
Opting to start plants in containers indoors to replant outside? Replanting is very simple. Prepare your soil in advance, dig a hole that will fit the plant and most of its soil ball, and then gently unpot. Make sure its roots aren’t too intertwined, then place it soil and all in its new location. Gently backfill with fresh soil.
Place a thin layer of compost over the soil at the plant’s base, and you’re done!
Common Problems
Bachelor’s buttons have very few pest or disease issues. Read on to learn how to defeat any which appear!
Growing Problems

The biggest problem that you’re likely to encounter is top-heavy plants. This is quite common with bachelor’s buttons, and is caused by excess moisture on the flowers. Using supports for your plants is the only real way to fix this. The stems are so slender that it’s easy to see how they can topple under the weight!
Another problem that may appear is yellowing foliage. Most often, this problem is caused by a watering issue, and both over-watering and under-watering may be to blame. Make sure that your soil drains well and that standing water cannot pool around your plants. Aim for consistent soil moisture, not too wet but not completely dry either.
Yellowing leaves can also be a sign of frost damage, and if this occurs, the plant may still survive. If it begins pushing out new growth in the spring, trim off yellowed leaves. Remember, this is an annual plant, and overwintering may not be an option.
Pests

Very few pests will bother cornflowers. In fact, it’s likely that only a couple sucking insects will stop by for a snack.
Some types of aphids may live on or under leaves. To wipe them out, apply neem oil to all plant surfaces. The oil smothers eggs and kills the adults. These are great treatments if a strong stream of water from a hose doesn’t do the trick.
Mealybugs are another sucking insect that may snack on your plant. While bachelor’s buttons are not their first choice, they still may be at risk. Use insecticidal soap to end their stay.
In addition to these, I’ve discovered that rabbits will nibble on the leaves of your plants. They won’t eat enough to do severe damage, but they do like the taste! In the non-pest department, small birds find the seeds delicious. They may also help get rid of caterpillars or other pests, so I consider them to be helpful.
Many beneficial insects are drawn to the flowers. Ladybugs help eliminate aphids, and pollinating insects such as bees make your garden thrive!
Diseases

Very few diseases will cause damage to your bachelor’s buttons. Here are two that might appear if you’re not careful!
Getting rid of powdery mildew can be a slow process. Neem oil works well but may take multiple applications. Weekly sprayings will reduce the chances of powdery mildew or pest infestation.
Spread by wind-borne spores, rust may also appear. This fungal disease causes yellow or white spots on top of leaves. Over time, spores appear on the underside of the leaves, and the plant’s growth may become stunted. Remove any damaged leaves and destroy them.
Frequently Asked Questions
Are bachelor’s buttons perennials or annuals?
They are annual.
Do bachelor’s buttons prefer sun or shade?
Bachelor’s button plants require either full sun or partial shade.
Are bachelor’s buttons invasive?
In some areas, they are. Before you plant them, check with your local extension office to see if they are.
Why do they call them bachelor’s buttons?
Bachelor’s buttons were put in the lapels of bachelors. Their rate of fading determined the strength of the love between the bachelor and the person he courted.
When should I cut back my bachelor’s buttons?
Cut them back at the end of their growing season, or before they grow too tall.
How long do bachelor’s buttons last?
They bloom from anywhere between four and ten weeks.
Can bachelor’s buttons survive frost?
No. They will die back in extreme cold or heat.
Are bachelor’s buttons easy to grow?
Yes! Try growing them!