Q What soil type suits hellebores best and why?
A It doesn't matter if the soil is acidic or alkaline, as long as it is full of nutrients and is free draining. In the wild, hellebores are often found growing on limestone, because these soils are usually richer in nutrients.
Caption: Hellebores, such as 'Penny's Pink', like rich, free-draining soil.
Q How can I improve my soil so it suits hellebores?
A You should always prepare the soil before planting by adding lots of organic matter in the form of old manure, leaf mould, etc. Spent mushroom compost is excellent because it is a sterile manure and contains a fair amount of lime, but you can't use this if you’re planting near ericaceous plants such as rhododendrons. Always make sure you loosen the soil around your plants after planting.
Caption: Improve the soil with organic matter and feed such as calcified seaweed
Q What sort of site do hellebores like?
Hellebores are very adaptable and seem happy in most sites, including north-facing borders. The main thing is to grow them under deciduous trees and shrubs, so they get sun when flowering in February and March, but are in shade when the tree and shrub leaves return. The deciduous trees and shrubs also tend to filter the strong, cold winds and offer protection from late frosts, both of which can damage the flowers when they open in mild spells. The exceptions to this rule are H. argutifolius and H. x sternii, which seem to grow better under a needle conifer such as a pine or cedar. Hellebores grow better on a slope so this naturally improves the drainage and helps when looking up into the hanging flowers.
Alternatively, hellebores also make excellent container plants. Grow them in a Best Buy compost for containers and add controlled-release feed each year.
Caption: Hellebores grow well in containers
Q What sort of plants make good neighbours for hellebores?
A Other early flowerers, such as Anemone blanda, aconites, Cyclamen coum, hepaticas and snowdrops are all good bed partners for hellebores. I like to grow them under acers, Cornus officinalis, hamamelis, and Ribes 'White Icicle'. For later in the summer, try hostas, peonies or geraniums, such as 'Ann Folkard' and 'Rozanne'.
Caption: Early flowerers, such as crocus and snowdrops, make good partners for hellebores
Q Do hellebores need feeding? If so, with what and when?
A Yes, as hellebores, especially the garden hybrids, are very hungry plants. Spent mushroom compost or calcified seaweed work well. Feed at the end of August or September, when the leaves tend to grow flatter to the ground.
Q Should hellebores be mulched?
A Mulching is useful, as long as you don't bury the new flower buds or growth, so only mulch very thinly around the neck of the hellebores. Spent mushroom compost is ideal, as long as there are no ericaceous plants nearby as it contains chalk.
Caption: Be careful not bury flower buds or growth when you mulch
Q What pests and diseases do hellebores suffer from?
A Greenfly is probably the biggest pest. Remove all the leaves off the H. x hybridus at the end of December, otherwise the mice tend to eat the flower buds. Young flower buds and leaves can suffer from ptritus and rot with the varying weather we seem to be having of late. Spray with a fungicide for ornamental plants. If hellebores develop black veins, these plants are best dug and burnt, as they've got hellebore black death.
Q How are hellebores propagated?
A Hellebores are best propagated by seed, but can be divided just after flowering or in September.
Q What should be done with the seedlings that naturally occur around established hellebore plants? How long does it take them to flower?
A To avoid them altogether, remove the old seedheads before seed pods start to release seed. Hellebores occasionally flower after two years, but it's usually three years. At this point, you can assess whether they're worth keeping.