Hellebores: Potted Plant Perennial
How to Plant
Planting Potted Plants in the Garden:
- Select a location in full to part shade with good rich moist organic soil. Choose a location where plants will not be as exposed to winter damage.
- Prepare the bed by turning the soil under to a depth of 6-12, inches removing any debris, and lightly raking as level as possible.
- The addition of organic matter (leaf mold, compost, well-rotted manure) benefits all gardens and is essential in recently constructed neighborhoods.
- Plant on a cloudy day or in late afternoon to reduce transplant shock.
- Dig a hole for each plant large enough to amply accommodate the root ball.
- Unpot the plant and gently loosen the root ball with your hands to encourage good root growth.
- Place the top of the root ball even with the level of the surrounding soil. Fill with soil to the top of the root ball. Press soil down firmly with your hand.
- Use the plant tag as a location marker.
- Thoroughly water and apply a light mulch layer on top of the soil (1-2 inches) to conserve water and reduce weeds.
How to Grow
- Keep weeds under control during the growing season. Weeds compete with plants for water, space and nutrients, so control them by either cultivating often or use a mulch to prevent their germination.
- In the spring, use a top-dressing of compost.
- Careful watering is essential in getting perennials off to a good start. Water thoroughly at least once a week to help new roots grow down deeply. Soil should be damp at about 1 inch below the soil surface. You can check this by sticking your finger in the soil. Water early in the morning to give all leaves enough time to dry. One inch of rain or watering per week is recommended for most perennial plants. You can check to see if you need to add water by using a rain gauge.
- Good air movement is also important.
- After new growth appears, a light fertilizer may be applied. Keep granular fertilizers away from the plant crown and foliage to avoid burn injury. Use low rates of a slow release fertilizer such as Garden-tone, as higher rates may encourage root rots.
- Cutback old foliage after blooming.
- Do not mulch in the fall for winter protection. This can smother that plant.
- Hellebores seldom need dividing and often self sow. Avoid disturbing plants once they are established.
- Hellebores are evergreen and bloom very early in the season.
- Hellebores make interesting, long lasting cut flowers.
- Note that hellebores are toxic if eaten to humans and animals.
Common Disease Problems
Alternaria Leaf Spot: Small, round reddish brown spots with white to gray centers form on the upper surface of the leaves and along the midrib. The lesions may encircle the stems and cause wilt. This disease is worse in warm, wet or very humid weather. Burpee Recommends: Avoid getting water on the foliage. Remove infected plant parts and do not work around wet plants. Provide plenty of air circulation. Contact your Cooperative Extension Service for fungicide recommendations.
Botrytis: This fungus causes a grey mold on flowers, leaves, stems and buds. It thrives in cool wet weather conditions. Burpee Recommends: Remove affected plant parts, avoid watering at night and getting water on the plant when watering. Make sure plants have good air circulation. Contact your Cooperative Extension Service for fungicide recommendations.
Hellebore Black Death: Caused by the virus Hellebore net necrosis virus. Plants become stunted, deformed and marked by black streaks and ring patterns. Burpee Recommends: Digging up all infected plants and destroying them. Control aphids, which spread the disease.
Hellebore Leaf Spot: This is a common fungus that causes brown patches on leaves and stems from spring through fall, particularly when plants are beginning to show new growth in spring. On stems it may cause them to collapse. Small black fruiting structures may be evident on dead plant tissue. Burpee Recommends: Remove all affected leaves and destroy them. Remove plant debris throughout the season.
Root Rots: A number of pathogens cause root rots of seedlings as well as mature roots. Burpee Recommends: Pull up and discard infected plants. Make sure your soil has excellent drainage.
Common Pest and Cultural Problems
Aphids: Greenish, red, black or peach colored sucking insects can spread disease as they feed on the undersides of leaves. They leave a sticky residue on foliage that attracts ants. Burpee Recommends: Introduce or attract natural predators into your garden such as lady beetles and wasps who feed on aphids. You can also wash them off with a strong spray, or use an insecticidal soap.
Leafminers: These insects bore just under the leaf surface causing irregular serpentine lines. The larvae are yellow cylindrical maggots and the adults are small black and yellow flies. They do not usually kill plants, but disfigure the foliage. Burpee Recommends: Remove affected foliage.
Plants die over the winter in recommended zones: Wet soils with poor drainage in winter can kill plants. Hellebores are also susceptible to wind burn. Burpee Recommends: Make sure plants are in a well-drained soil. For container grown plants, add one zone colder than your zone when selecting varieties, and keep containers in a protected area outside, mulch heavily. Plant in an area protected from winter winds.
Slugs: These pests leave large holes in the foliage or eat leaves entirely. They leave a slime trail, feed at night and are mostly a problem in damp weather. Burpee Recommends: Hand pick, at night if possible. You can try attracting the slugs to traps either using cornmeal or beer. For a beer trap, dig a hole in the ground and place a large cup or bowl into the hole; use something that has steep sides so that the slugs can’t crawl back out when they’re finished. Fill the bowl about ¾ of the way full with beer, and let it sit overnight. In the morning, the bowl should be full of drowned slugs that can be dumped out for the birds to eat. For a cornmeal trap, put a tablespoon or two of cornmeal in a jar and put it on its side near the plants. Slugs are attracted to the scent but they cannot digest it and it will kill them. You can also try placing a barrier around your plants of diatomaceous earth or even coffee grounds. They cannot crawl over these.
Vine Weevil: This insect cuts irregular notches in leaf margins and grubs feed on plant roots, sometimes causing the death of the plant. Adults are approximately 5/16 inch long, dull black with dirty yellow marking on the wing cases. The grubs are c-shaped, 3/8 inches long, with light brown heads. Burpee Recommends: Handpick adults at night, shake the plants over newspaper to dislodge them. Check under pots where they hide during the day. Check with your Cooperative Extension Service for pesticide recommendations.
When will my hellebore bloom? Bloom time is dependent on the variety. Some varieties will bloom as early as February and others are fall bloomers.
Why is my hellebore yellowing? During the summer hellebores experience a “dormant” period. When the weather begins to get cooler, they begin to green up again.
Do hellebores need a lot of water? Hellebores can withstand dry conditions. When it has been exceptionally dry, be sure to give them water.
What can hellebores be used for? Cut flowers, borders, beds, containers, fillers.
Are hellebores deer resistant? Yes, and very poisonous.