Grow Hellebores Indoors: Bedroom Gardening Tips

Hellebores are a genus of flowering plants in the Ranunculaceae family, which includes anemones and delphiniums. They are prized for their unusual and pretty flowers, which bloom in winter or early spring. While they perform best outdoors, they can be grown indoors with a little trickery.

To grow a hellebore in your bedroom, you will need to find a cool space for it to experience four to six weeks of cold temperatures between 40 and 45 degrees Fahrenheit (4-7 degrees Celsius). You will also need to provide rich, well-drained soil and choose a large container, as hellebores don't like to be transferred.

Hellebore care tips for growing indoors

Temperature and Placement

Hellebores typically bloom in late winter to early spring and are known for their unusual and pretty flowers. They can be grown indoors, but they require a period of cold temperature between 40 and 45°F (4-7°C) for four to six weeks to produce flowers. This can be achieved by placing them in a cool location like a basement or garage. When bringing the plant indoors, allow it time to adjust to the temperature difference. Place the hellebore in a cool room, away from direct sunlight, and near a northern or eastern window for indirect sunlight.

Soil and Watering

Hellebores should be planted in a pot with drainage holes and rich, well-drained soil. Use a good potting mix or add compost to the existing soil. Keep the soil moderately moist, allowing the top layer to dry out during the winter. Avoid overwatering to prevent root rot.

Maintenance and Feeding

Trim off dead or damaged leaves to maintain the plant's appearance. After blooming, trim off the spent flower stems. Feed the plant with diluted balanced plant food in early spring and every three weeks until fall. Repot the hellebore every couple of years or when it becomes root-bound.

Pests and Diseases

Hellebores are generally easy to care for, but they can be susceptible to pests like aphids. Remove affected parts and spray with horticultural oil or pesticide. Common diseases include leaf spot and downy mildew, which are fungal infections that can be treated with fungicides. "Black Death," caused by the Helleborus net necrosis virus, is a serious disease with no cure, and affected plants must be removed to prevent its spread.

Choosing the right container

Hellebores are deep-rooted plants, so the depth of the pot is particularly important. Choose a container that has a good depth and is slightly wider at the top than at the base. This will ensure that you can easily remove the plant when it needs repotting. Hellebore plants don't like to be transferred, so it's best to choose a container that is only slightly bigger than the existing pot. This will prevent the plant from becoming waterlogged in unused compost.

The roots of a hellebore grow mostly down, so the depth of the pot is critical. Choose a large container to give your plant room to grow and minimise the stress of moving it. Hellebores need rich and well-drained soil, so be sure to select a pot that drains well. Use a rich organic potting soil or add compost to the existing soil.

Stand the container on pot feet to improve drainage. Hellebores are hungry plants and will need regular watering and feeding. Position the container where you can enjoy it from the house during flowering, then move it to a semi-shaded position in the summer. Repot your hellebore every couple of years with fresh compost or plant it directly in your garden.

Preparing the soil

Dig Deep

Hellebores are deep-rooted plants, so it is important to dig your soil as deeply as possible. This will provide the necessary space for their roots to grow and allow them to access nutrients from deeper in the ground.

Mix in Organic Matter

To support the growth of hellebores, it is recommended to mix in plenty of organic matter into the soil. This can include humus in the form of leaf mould, spent mushroom compost, garden compost, or well-rotted manure. By adding these amendments, you will be providing the nutrients that hellebores need to produce an abundance of flowers.

Test the Soil pH

Before planting hellebores, it is a good idea to test the pH level of your soil. Hellebores prefer neutral to slightly alkaline soil conditions. If your soil is highly acidic, you can add lime to adjust the pH towards the neutral to alkaline range that hellebores favour.

Ensure Good Drainage

Hellebores thrive in moist soil, but it is crucial that the soil drains well. They are susceptible to root rot if left in wet or waterlogged conditions for extended periods. To improve drainage, consider planting your hellebores on a sloping bed or mounding the soil slightly before planting.

Avoid Over-Fertilization

While hellebores benefit from nutrient-rich soil, too much nitrogen can lead to an abundance of foliage at the expense of flowers. Therefore, it is generally recommended to avoid fertilizing hellebores unless the soil is lacking in nutrients. A layer of organic matter, such as compost or manure, applied annually should provide sufficient nutrients for your hellebores without causing an excessive amount of foliage growth.

Container Gardening

If you are growing hellebores in containers, choose a good quality, loam-based compost. Ensure your container has adequate drainage holes and is slightly larger than the plant's root system to prevent waterlogging. Keep the soil moist but not soggy, and feed your hellebores regularly with a high-potash fertilizer during the summer months.

Watering and fertilising

Hellebores are low-maintenance plants that can do without regular fertilising or watering. However, fertilising and watering can help them thrive.

Watering Hellebores

Hellebores are woodland plants that prefer moist, well-drained soil. They need deep watering at least weekly after planting to help them establish themselves. Once their roots are established, they can tolerate drier soil conditions but perform best in moist soil with regular watering.

You can tell if your hellebore needs watering by checking if its leaves are wilted. If the leaves turn yellow and then brown, it means they did not receive water in time. Water your hellebore immediately if you notice this.

New hellebores should be watered immediately after planting to saturate the site and fill any gaps in the soil. Continue to water deeply every few days if rainfall doesn't occur for the first couple of weeks.

Established hellebores need an inch of water a week from rainfall or watering, from spring to fall. They do not need watering during winter.

Potted hellebores should be watered when the top layer of soil feels dry, about once a week, during their growing season. During extended dry periods in winter, water them when the leaves begin to wilt and temperatures are above 40°F.

The best time to water hellebores is early in the day so that any moisture on the leaves has time to dry before nightfall. This lessens the chance of fungal infections.

Fertilising Hellebores

Hellebores are not heavy feeders, but feeding can improve plant growth and floral performance in subsequent years. Most hellebore species are considered woodland plants, so mimicking this environment can help nourish your plant. You can do this by applying an annual mulch or adding fertiliser to the soil.

Feeding is best done in late spring, once your hellebore has finished flowering. While this will vary depending on the species and your location, it is usually in May or June.

When feeding, it is recommended to use an organic general feed. You can also apply a good layer of compost or mulch to borders to help feed the soil, retain moisture, and suppress weeds.

Common pests and diseases

Hellebores are not usually plagued by many pests, and their toxicity means deer and rabbits avoid them. However, there are a few pests and diseases to watch out for.

Aphids

The most common pest is the hellebore aphid, a whitish-green insect that can be found on the flowers and foliage of hellebores in spring. These sap-sucking bugs leave behind a sticky residue known as "honeydew", which attracts ants and sooty mould. The hellebore aphid is also a vector for the Helleborus net necrosis virus, which causes a disease known as Black Death. This disease results in stunted plants and black streaks. If a plant is affected by Black Death, it must be removed entirely.

To control aphids, you can:

• Squash them between your fingers if there are only a few
• Use a strong blast of water to dislodge them
• Introduce predatory lacewing larvae as a biological control
• Apply organic sprays or insecticidal soap
• Use synthetic pyrethroids for longer-term control

Leaf Miners

Helleborus foetidus, or stinking hellebore, is the only species affected by Phytomyza hellebori, a small fly that lays eggs in the foliage. When the eggs hatch, the larvae tunnel inside the leaves and feed on the plant tissue, causing cosmetic damage. To control leaf miners, cut off the damaged leaves and destroy them to prevent the larvae from pupating.

Slugs and Snails

Hellebores are highly susceptible to slugs and snails, which can sneak up the stalks and devour the flowers as well as the foliage. Control methods include hand-picking and setting traps.

Vine Weevils

The adults of these pests munch on the foliage, leaving irregular notches in the leaf margins. However, it is the grubs that cause the most damage, feeding on the roots and stem bases. To control vine weevils, you can handpick the adults or use biological controls such as beneficial nematodes.

Hellebore Leaf Spot

This is a common fungal disease that infects the leaves and stems of many hellebore species, causing roundish, dead, brown spots. It is caused by the fungus Microsphaeropsis hellebori and is particularly damaging to Helleborus niger. To control hellebore leaf spot, remove and destroy all affected leaves promptly and do not allow infected material to remain around the plants. The RHS recommends against the use of fungicides, as they may reduce biodiversity and impact soil health.

Frequently asked questions