Hostas for Colour, Form and Substance
by Sally Gregson

In our modern, smaller gardens, as our favourite shrubs grow bigger and even small trees get taller, there is increasingly more shade: an opportunity to grow some of the loveliest plants in the gardening canon.
Shady ladies are often quite fleeting: wood anemones, corydalis, dog’s tooth violets, to name a few, and they need the foil of longer-lasting foliage plants to create cohesion in the border. The complex leaves of ferns and astilbes are lacy and pretty, but hostas bring colour, form and substance to the party. Their beautiful foliage, as big as dinner-plates or as small as feathers,  blue or acid green, variegated or margined, creates huge mounds or tiny islands among the ephemera.
It’s no wonder that hostas have inspired passion among gardeners and plant breeders alike, both in Europe and in the United States. The latest hostas are being bred as much for their flowers as for different foliage. There’s Hosta 'Zounds', with pale lavender flowers against large, golden yellow leaves, like shining seersucker. The wavy, white-margined leaves and lilac flowers of H. 'Praying Hands’ stand straight up and curve inwards to show off their strong vertical veins. And H. ‘Fire Island’ also has lavender flowers and golden leaves that stand erect to expose bright red leaf-stalks.
Hosta ‘Fragrant Bouquet’ is perhaps one of the most well-known perfumed varieties, with its apple-green, cream-margined leaves and pale flowers that are especially well-scented in sun. And H. ‘Cherry Berry’ is a smaller plant whose purple flowers have bright red flower-stalks that cut quite a dash against the white and green variegation. Any of these plants would merit growing in loam-based compost in a container.
In the garden, hostas prefer shade and damp, although many varieties will tolerate sun for part of the day without scorching. The soil should be improved with plenty of organic matter, mulched in the autumn, and a little organic fertiliser sprinkled around the crown in early spring.
It’s easy to make more by lifting the whole crown in February before the buds start to swell. Wash off the soil so that you can see what you are doing. It’s all too easy to damage the buds. Push two forks, back to back, into the centre of the crown and prise them apart. Repeat the operation in the opposite direction so that you have four quarters. Discard the older part at the middle of the plant if it seems weak, and replant the quarters in soil improved with garden compost or well-rotted manure. Then, in late spring, your new hostas will burst forth with even more enthusiasm to chaperone those blossoming shady ladies.
 

Hostas and slugs

• As every gardener knows, slugs and snails are the main problem, and after last summer’s rain, there are more of the slimy army around than ever before. Fortunately, there are lots of organic and chemical pesticides on the market, as well as traps such as slug pubs.
• A dressing of grit does not impede the progress of a determined slug or snail, and quite often it’s the tiny black slugs that live under the soil that damage the buds while they are still dormant. For that reason it’s important to start as early as February with whatever measure you choose.
• The microscopic nematodes Phasmarhabditis hermaphrodita are very effective for up to six weeks. They can be applied to the soil as soon as its temperature reaches 5ºC (40ºF) in early spring, and again in autumn to kill any over-wintering malingerers.
• Copper rings have been proven to be the most effective barrier method. They can be placed at soil level around each plant, or around the inside rim of a container. They will probably need renewing each year.