By Diana Guy
A Woodland Garden
This may be a proper little patch of woodland or just a little group of three trees, or even the shade cast by one big specimen. You will probably have to prepare the soil thoroughly before planting, adding lots of mulch such as good garden compost or spent mushroom compost, and the addition of further mulch must become an annual ritual.
These conditions lend themselves well to most hellebores, especially Helleborus x hybridus and Helleborus argutifolius, but the inter-species cultivars (and Helleborus nigercors and Helleborus ericsmithii types) will probably be happier on the edge of the patch where shade is lighter.
Remember, they are summer dormant, so in woodland that can mean a degree of drying out in the summer, hellebores can acquire the flattened starfish look. They will not suffer too much as a result, but in extreme drought conditions just give them a bucket of water once or twice in the season.
They will associate well with all the usual spring woodland tribe: pulmonarias, wood anemones, corydalis, dicentras, and to follow on: epimedium, Solomons seal, brunnera, ferns, primroses, violets, Geranium phaeum and Geranium nodosum. Bulbs go well, choose dainty varieties. Early spring bulbs could be followed by bluebells perhaps, but do not let the bluebells encroach too closely. Narcissus are fine companions too, but I think the paler, smaller varieties such as February Silver look best. Shrubs such as daphne and sarcoccoca, or, if the conditions are right, witchhazel, all add the welcome dimension of scent.
Follow on planting can include aquilegia, digitalis, bergenia, Geranium nodosum and Geranium macrorrhizum, honesty, hostas, tiarellas and tellimas, Euphorbia amaglyoides, Euphorbia robbiae, Alchemilla mollis and convallaria (but the last 3 should not be planted too closely).
Tropical or Exotic Borders
I am presuming a fairly open border with good rich soil and partial shade only. The main show is likely to be mid summer to late winter as most of the planting is likely to be of a tender nature, planted out in May. However, if your border is visible from the main vantage points you will need something to look at in winter and spring. Hellebores are perfect – good foliage in late autumn through to winter, when the border has been cleared. Colour through winter and spring. Good foliage then emerges to give texture and interest until planting out time in May.
Choose varieties that give good foliage – which is most of them. Helleborus hybridus and some of the bolder taller inter-species crosses will cope with being shaded out later in the season by the big stuff. Helleborus argutifolius is tall and very architectural but would be better placed near the front, as would Helleborus x sternii and the Helleborus x ericsmithii cultivars.
Permanent planting: Fatsia japonica, hemerocallis, melianthus, Miscanthus Cosmopolitan.
Temporary planting: certain salvias, cannas, dahlias, bananas, hedychium, eucomis, and many the other tender tropicals.
Foliage, Shade or Green Border
This is a variation on the above, as it could still look quite exotic and architectural but is also adaptable to shady positions. So presuming shade for much of the day, I would use mainly Helleborus hybridus. Remember they are not shade lovers, rather, they are shade tolerant. A good foliage Hellebore is Helleborus multifidus, with very finely divided leaves, however it could take some tracking down!
Ferns, hostas, bamboos (but not too close!), Hedera colchica (Persian ivy), Fatsia japonica, Mahonia japonica, hollies, aucuba, Arum italicum marmoratum.
Sunny, Gravel or Mediterranean border
I am presuming reasonable soil beneath the gravel but fairly free draining and sun for much of the day. Helleborus argutifolius, Helleborus x sternii and some of the inter-species crosses such as Helleborus x ericsmithii could cope, unless the site is really parched in which case only Helleborus argutifolius would work.
Euphorbias such as Euphorbia characias (there are many forms to choose from), Euphorbia polychroma, Euphorbia myrsinites, nepeta, Phlomis italica and Phlomis russeliana, eryngiums, artemesias, sedums, cerinthe, cardoons, papavers, agapanthus, Perovskia Blue Spire, verbascums.
The Mixed Border - planted for all year round interest
I am presuming good soil and a fairly open situation that receives reasonable levels of sunshine. Most of us will be using hellebores in mixed borders and would probably love to achieve something like the glorious long borders at Dixter! Consider which hellebores do not mind being shaded out by the plants that will grow up in front and around them as the season progresses. Helleborus hybridus are amenable in this respect. Put Helleborus argutifolius and tall varieties of Helleborus x sternii where the newly emerged architectural foliage will be seen (plants may need staking). Lower growing Helleborus nigercors and Helleborus ericsmithii and similar inter-species cultivars will need to maintain their own space, probably at the front of the border. Do not let them be smothered by the foliage of plants that emerge later.
Hellebores can provide colour from as early as late November until well into April, by then the new foliage is through, and this will add texture to the border.
The border should be planned around a good framework of shrubs and maybe small trees. Perennials should be chosen to give interest either at various different times of the year, or to provide a long period of interest by sustaining their flowering for extended periods. Annuals will give good colour from summer to autumn, biennials from spring to summer and bulbs can be chosen for almost every month.
Perennials: Hardy geraniums associate, but keep an eye on the good doers such as Geranium phaeum and Geranium oxonianums as they can encroach. Divide them regularly. Hemerocallis share similar cultural requirements as Helleborus hybridus and the latter will appreciate the shade provided by the hemerocallis foliage as it develops and matures. Other plants to associate with Helleborus hybridus include astrantias, iris sibirica, papavers, francoas, sedums, most euphorbias, rudbeckias, Japanese anemones; annuals such as cosmos, Nicotiana sylvestris (this will cope with shade, too,) cerinthe (for sunny and dry) - indeed almost any annual or non invasive perennial.
PLANTS TO BE WARY OF: anything that is invasive - comfrey, vinca, asters - keep an eye on certain hardy geraniums.
I am never sure about grasses. Do they go together?
On the whole, hellebores do not like to be grown in containers. The inter-species cultivars and even Helleborus niger seem to do better in a LARGE pot than Helleborus hybridus. Pots can get too hot and dry in summer, so ensure potted specimens are moved to a shady spot for the summer and do not let them dry out. In winter plants can become very desiccated by cold drying winds and their roots vulnerable to freezing in very frosty conditions, so in winter put the pots in as sheltered a position as possible - inside an open porch is ideal, or against the house wall. Do not overwater. If you buy a smart new hellebore or two, it is nice to create a temporary display by plunging the potted plants into a large container of multi purpose compost and then planting around them with interesting foliage plants such as bergenias and euphorbias. Then in late spring dismantle the display and plant them out into their permanent positions. It is a good excuse to buy a few new ones the following winter! Best varieties to use are Helleborus x ballardiae, Helleborus x ericsmithii and Helleborus x nigercors (under whatever names!) and Helleborus x sternii, Helleborus Annas Red and Helleborus Pennys Pink.
If you have to keep hellebores in a container for a while, plant them out into as big a container as you can, using a mix of multipurpose compost, garden soil, leaf mould if you have it and some mushroom compost. Most of the above will appreciate some grit added to aid drainage. Feed with bonemeal in early autumn and mulch in early winter and spring with mushroom compost.
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