by Erin Marissa Russell
Do you love the attention-grabbing glamour of flowers with tall vertical spires, like hollyhocks and larkspur? If you’re also a fan of low-key monochromatic sophistication, bells of Ireland flowers, with blooms in shades from artichoke to emerald, will make a wonderful addition to your garden’s repertoire. The plants reach two to three feet in height, making them a natural fit for the back row of your flowerbed. The summer-blooming half-hardy annual’s unique scent (reminiscent of green apples) and its suitability for fresh or dried floral arrangements give gardeners even more reasons to cultivate this chartreuse beauty.
Since 1570, bells of Ireland have been tended by horticulturists who appreciate the drama of their showy flower spikes, the lush greenness they add to a garden’s palette, and their distinctive smell. They’re still a hit today, and it’s easy to see why. The green bells stacked densely on each stalk range from three quarters of an inch to an inch and a quarter, with a tissue-paper feel and scalloped edges. Each bell hides a delicate white or pink flower that blooms once per season. Between the bells are lush leaves, each about two and a half inches long, and each bell sits atop a pair of spiny thorns.
Before we get into how to sow, grow, and care for bells of Ireland flowers, let’s dispel a few of the myths that surround this member of the mint family. First of all, the name aside, these flowers don’t hail from the Emerald Isle, though like the Irish, bells of Ireland are associated with luck. The Latin name, Moluccella laevis, is also both location-centered and misleading. Linnaeus, who named bells of Ireland, was under the impression they came from the Molucca islands in Indonesia. In actuality, these flowers come from western Asia—to be specific, Turkey, Syria, and Caucasia. Secondly, the showy green “bells” aren’t exactly the flower of the plant. The green cup-shaped parts of the bells of Ireland are actually the sepals that make up the calyx. The teeny white blooms, which look a bit like miniature orchids, sit tucked away within the bells.
Varieties of Bells of Ireland
You may see bells of Ireland called shellflower or referred to by their botanical name, Moluccella laevis. In Australia, they’re also known Molucca balm or Moluccella balm. The “Pixie Bells” cultivar grows to just 18-24 inches (as opposed to the standard two-to-three-foot size), making it an excellent choice for growing these gorgeous flowers in containers.
Growing Conditions for Bells of Ireland
Bells of Ireland are suited for USDA zones 6 through 11. They are tolerant of heat but do not thrive in climates that are both hot and humid. Some gardeners report that due to this preference, they are not easy to grow in the southern U.S.
The best spot to place bells of Ireland is in full sun, but if needed, they can be grown in partial sun. These flowers prefer their soil on the rich and loamy side, but average soil will suffice if fertilizer is applied to compensate. Choose a spot with good drainage, as bells of Ireland don’t flourish when waterlogged or starved of moisture.
Prepare soil for bells of Ireland by removing gravel and weeds, then working compost into the top six to eight inches. Finish by leveling the soil and smoothing it down. For optimal performance, test soil after each growing season to find out what adjustments are needed before the next season begins.
If compost isn’t an option, you can instead add one or two inches of mulch after planting bells of Ireland, though it’s best to wait until after seeds have germinated so they get the light they need to sprout. The mulch will break down into compost as the plants grow. Just make sure to keep mulch away from the stems to avoid problems with rot.
Gardeners in Florida and South Texas can grow bells of Ireland as a fall annual by germinating seeds in the fall. Simply refrigerate seeds for a week before sowing them along with the rest of your fall annuals.
How To Plant Bells of Ireland
While you have the option of sowing bells of Ireland directly or starting them indoors, not to mention choosing young plants from a nursery, direct sowing is recommended. These plants use a long taproot to gather nutrients from the soil, and that taproot doesn’t like to be disturbed, so transplanting can present challenges. When transplanting can’t be avoided, be as gentle with the roots as possible. If you do choose to start bells of Ireland indoors or purchase your plants and then place them in the garden, don’t expect maximum performance their first year. If allowed to self seed, the following season’s plants will be taller and more prolific.
When choosing bells of Ireland seeds, you’ll see both raw and cleaned seeds on the market. Cleaned seeds are generally recommended and easier to grow. Bells of Ireland can be fussy in the germination phase, so for best results, sow more seeds than you think you’ll need. You can always thin your plants out. Germination is often more successful outdoors than it would be indoors because these flowers enjoy chilly, wet conditions.
To speed up the germination process and increase each seed’s chances of success, prep seeds by chilling them in your refrigerator before you sow. Moisten a paper towel evenly, and place the seeds on the paper towel. Fold the towel to fit inside a plastic sandwich bag, seal the bag, and store in the refrigerator for two weeks.
To sow bells of Ireland directly where they’ll grow, plant them in the fall about a foot apart, and cover with a quarter of an inch of fine soil. Take care not to cover the seeds too much, as they need light to sprout. Instead of one seed per foot, you may choose to plant groups of three and thin to the strongest plant when seedlings start to grow. Firm the soil lightly with the palm of your hand, water it well after planting, and keep the area evenly moist. Young plants will appear in seven to 14 days if seeds have been prepped in the refrigerator. Otherwise, germination can take up to a month.
If you choose to start bells of Ireland indoors, plant them eight to 10 weeks before the last frost of the year. Young plants can resist light frost, but a sudden freeze can damage them. A seedling heat mat can speed up the process as well, if you have one on hand, but be sure to remove it as soon as germination occurs. Barely cover the seeds with soil so light can reach them. If possible, use grow lights to ensure the seeds get the light they need. Position grow lights two or three inches above the soil, and keep them on for 18 to 20 hours per day.
Water seeds and seedlings frequently, and do not let the soil dry out. Harden off young plants grown indoors by exposing them to the elements in gradually increasing blocks of time before transplanting them outdoors. Wait until overnight temperatures stay above 40 degrees Fahrenheit to move bells of Ireland to the garden.
Care for Bells of Ireland
During the growing season, bells of Ireland require about an inch of rainfall per week. If your rain gauge falls short, water the plants yourself to make up the difference. Soil for bells of Ireland should be kept evenly moist but not overly saturated. A drip or trickle irrigation system that gently adds water to soil is best, but if you use overhead sprinklers, simply water early in the day so the plants can dry before nightfall to prevent disease.
Monthly, administer a balanced water-soluble fertilizer to get the most out of your plants. Use a liquid fertilizer in early summer, and really lay it on thick to encourage lush growth. Keep weeds at bay to let bells of Ireland make the most of the soil’s nutrients.
Because these showy flowers stretch so high, you’ll need to protect them from high winds either by placing them in a spot with a windbreak, such as a fence, or by staking. Stake plants while they are still young.
If flowers are left to dry in the garden, bells of Ireland will often self seed. In fact, some gardeners say they self seed “like crazy.” Seeds are dark in color and can be either collected to plant next year or left where they fall. If you don’t want to see these flowers return year after year, be sure to harvest the flower spikes for arrangements before they have a chance to dry.
Garden Pests and Diseases of Bells of Ireland
Watch leaves for small flecks with a yellowish halo that eventually turn brown, as this sign indicates cercospora leaf blight. If plants are wilting at the soil line to finally die back, your plants may be facing crown rot.
Keep an eye out for the tiny bugs and sticky residue that point to an infestation of aphids. A healthy population of natural predators, such as lady bugs or wasps, can help keep aphids under control, as can insecticidal soap. Visible webbing on plants or yellowing, dried-out foliage can mean tiny spider mites are making a meal of your plants. Hot pepper wax or insecticidal soap should solve a spider mite problem if one crops up.
Using Bells of Ireland in Arrangements
Harvest the flowers regularly to use in fresh or dried arrangements to promote the blooming of side shoots. Bells of Ireland spires stay fresh for eight to 10 days in fresh-cut arrangements. Remove the leaves before arranging to make the bouquet even more beautiful. The stems of these stunning, spiky flowers are hollow, making them a challenge to use with floral foam, but this setback can be overcome by inserting a wire into the stem before using.
To collect bells of Ireland for fresh arrangements, cut the flower spikes when they are the desired height and when half the bells are open and green. Keep fresh arrangements in a cool, shady area for the longest vase life.
Dried bells of Ireland fade from their characteristic green shade to a pale beige. Cut the flowers for drying in mid to late summer, when they’re blooming most productively and bells are fully open. Hang the stalks in small bunches upside down in a dry, airy location until they’ve dried out completely.
Want to Learn More About Bells of Ireland?
Looking for a quick introduction to these stately plants? The link below will bring you to a slideshow of facts about Bells of Ireland that’s just over two minutes long:
If you’re trying to decide whether to grow Bells of Ireland from seed or purchase young plants, this clip examines the extra work involved with cultivating your plants from seed:
Here’s an in-depth look at the process of preparing soil and planting Bells of Ireland seeds from Carrie’s Gardening Channel, and Carrie also discusses solutions to some common problems gardeners experience:
This slideshow video shows Bells of Ireland in various arrangements and planting setups that may inspire you when it comes to companion plants, creative containers, or cut flower bouquets:
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