Moluccella

( mol - yew - SELL - uh )

At-A-Glance Information

Commonly called Bells of Ireland or Shellflower, this genus includes species of flowering herbaceous annuals which need full sun and regular water to perform well. One species is commonly cultivated (Moluccella laevis), and is popularly used in flower arranging. Plants are native to the Middle East, and reach around 2-3 feet tall and 10 inches wide at maturity. Flowers are inconspicuous and white, concealed within a bell-shaped green calyx. The calyces are long-lasting in dried and fresh arrangements. Cultivar 'Pixie Bells' is a compact variety that grows to 20-24 inches tall. Moluccella is a member of the plant family Lamiaceae and includes 8 species. Bells of Ireland grows best in USDA hardiness zones 2-11 or Sunset growing zones 1-24, H1 and H2. To find your zone, click here: Zone Map.

Caring for Moluccella

Moluccella, or Bells of Ireland, can be grown from seed (started indoors or direct sown in the garden) or purchased as a specimen from a reputable nursery. Bells of Ireland does well in full sun; ideally these plants should be getting between 6 and 8 hours of sun each day for the best blooms. In warmer climates, make sure that they get some afternoon shade during the warmest hours of the day. If these flowers are not grown in sufficient sun, they will tend to get leggy and flowering stems will flop over and be unusable for arranging. Even when grown in full sun, it is helpful to have structure for Moluccella flowering spikes, such as stakes or netting. They appreciate quick-draining soil that has an around neutral pH (between 6.5 and 7.5). They appreciate some soil richness to perform well; If local soils are particularly poor in nutrients or do not drain well, make sure to amend the planting area with plenty of organic compost before installing. Apply a thick layer of mulch around the planting area to suppress weeds, maintain soil temperatures, and increase soil moisture retention. Water new plantings regularly as they establish a strong root system. These plants like consistently moist soils at maturity; apply about an inch of water per week for best results.

Fertilize yearly in early springtime with an application of 2 inches of compost around the base of plants. Pull mulch back before applying, work the compost gently into the soil a bit, water it in, and then replace mulch. These plants are not heavy feeders, and this should be sufficient to provide the necessary nutrients for the active growing and flowering seasons. Minimal pruning is required for these plants, though spent flowering spikes can be removed as they fade to clean up the look of the plant. Once Bells of Ireland are cut, the plant will not bloom again. Leggy growth can also be pruned back to cultivate a bushier form. Plants begin to diminish and turn brown in late July into August. These are annual plants, and can be removed at the close of the growing season at the end of summer or early fall. Moluccella plants are short-lived perennials that are often treated as annuals, pulled and composted at the end of the growing season and replaced in the next. In areas where they are treated as perennials, they can survive in the landscape for a few years before needing to be replaced.

Growing Moluccella in Containers
Bells of Ireland does well in containers, making them great architectural choices for container gardens and patios. Plant them in the center of the container, so that their tall spires can be surrounded at their base with mounding or trailing annual plants. Ensure that the container is at least 10 to 12 inches deep to accommodate healthy taproot growth and that it has adequate drainage holes. Fill container with a well-draining substrate; if substrate does not drain well, amend it with plenty of organic material and/or perlite before installing plants. Cover the soil surface with a layer of organic mulch to suppress weed growth, maintain consistent soil temperatures, and increase soil moisture retention. Make sure that mulch stays a few inches away from stems to discourage fungal diseases. Bells of Ireland grown in containers will need more frequent waterings than those grown in the ground. As a general rule of thumb, water whenever the top inch of soil feels dry to the touch. These plants do not need to be repotted or 'potted up' as many other plants do; they are annuals and get replaced each year, and also grow from a sensitive taproot that does not appreciate being messed with.

Harvesting Moluccella
Take care when working with and harvesting Bells of Ireland flower spikes, as there are small, spiny thorns that grow along the stems. Wear protective gear. The flowers are highly sought after as members of fresh or dried flower arrangements, and have a scent that is described as pleasant and sweet, with a hint of citrus undertones. Cut flowering spikes off of the plant when the bells are about half open. The best time to cut fresh flowers is in the early morning the day after plants have gotten a good watering. Plop cut stems in a bucket of cool water immediately to preserve freshness. Bells of Ireland have a vase life of about two weeks. To harvest for dried flower arrangements, leave flowerings spikes to develop on plants until fully open bells have become firm to the touch. At this time, remove the flowering spikes and leave them in a dry, cool, place to dry out. Flowers will turn tan and do not maintain their green color when dried.

Propagation

Moluccella, or Bells of Ireland, plants are best propagated through harvesting and sowing seed. These plants will reseed freely in the landscape, and volunteer seedlings can be dug up and replanted while they are young. Avoid transplanting more mature plants, as they have sensitive taproots that do not like to be moved. To propagate your Bells of Ireland plant using seeds, follow the instructions below:

Propagating Moluccella by Seed

Keep in mind that the plant you get from seed will not necessarily mimic all of the characteristics of the parent plant. To propagate by seed, you will need a paper bag, a pot or tray filled with well-draining compost or other organic material, a spray bottle and a fork. The best potting medium for seed germination is a light blend of 1/3 pasteurized soil or compost, 1/3 sand, vermiculite or perlite, and 1/3 coconut coir or peat moss.
Harvest your seeds. The seed heads on plants are pretty easy to spot, they're left behind after flowers have faded. Once they have dried out and begun to split open, you can harvest the seeds inside. Cut them off of the plant, placing them in a paper bag. Harvest as many as you can, and place the paper bag in a dry, cool, dark area. They will continue to split open and release the seeds contained inside. Once they have been released, take them out of the bag and put them in a container so you can work with them.
For Moluccella seeds to germinate, they will need to undergo a process called 'cold-stratification', which mimics the conditions seeds would experience in their native environment. To complete this treatment, place seeds in a sealable bag or other container filled with moistened sand or peat moss, and then place that container in the refrigerator or a similarly cool environment. Leave the container there for about a week, and then remove seeds and get ready to sow them.
In either late winter or early springtime, get your container prepared. Water your prepared seed tray or pot filled with soil, and ensure that good drainage is occurring. Place your seeds in your prepared pot or seed tray about a quarter inch to a half-inch under the soil surface. Cover them with soil and water with your spray bottle. Place your tray of seeds in a warm area that receives bright, indirect light. A greenhouse is the most ideal climate, but a planting tray inside a window will do as well. Germination usually takes 12-21 days from sowing. Once you begin to see seedlings sprout and they are able to be handled, transplant them to their own individual 3-inch pots, filled with the same potting medium as described in Step 1. Loosen the seedlings from the potting medium by digging down with the tines of your fork about an inch and a half, gently working the seedling up until it is out. Then, replant the seedling in its individual pot.
Keep the seedling's potting medium moist, but not wet, by spraying the soil with your spray bottle. Keep your new plant in an area with bright light (though not direct sunlight) and temperatures between 65 and 72 degrees Fahrenheit. Ensure that the soil stays moist, but not wet, until the next spring (after the danger of frost has passed), when you can transplant it to its new home.

Bells of Ireland seeds form within the calyx cups on flower spikes.

Moluccella seeds.

Problems and Pests

Bells of Ireland, or Moluccella, plants are typically free of pest and disease issues in the landscape. They can, however, be a bit susceptible to developing problems with the following when plants are stressed: