Heavenly hostas
These vibrant beauties are fab at filling tricky gaps – but only if you can defeat their slimy foes
LET’S play a little game of word association. Without hesitation, say the first thing that springs to mind when you see the plant name… hosta. Unless you’ve been incredibly lucky in raising these showy, leafy perennials, the chances are it will trigger one of these words – slugs or snails.
Such a response isn’t too surprising. Hostas are martyrs to these pesky gastropods, which are drawn towards emerging shoots early in the season, and like to chomp holes in the leaves once they are fully unfurled. Badly damaged plants look ghastly and will ruin any displays they are a part of.
Over the years I’ve met many gardeners who have given up growing hostas due to sustained attention from these pests. Throwing in the towel is unnecessary. There are lots of clever ways to grow hostas to prevent them from being ravaged, and even varieties that are more resistant to attack.
The key to keeping hostas in good shape is to start your campaign early. Launch a pre-emptive strike against snails over winter, hunting them down as they hibernate. Look under pots, greenhouse benches, in the corner of sheds, behind trellis or at the base of hedges.
Slugs are much harder to track down – the pests remain active all winter if temperatures are above 5C and only a few are found above ground, with 95 per of the population living in the soil. They migrate upwards at night, on damp days or when the weather is overcast.
They are partial to the pointed shoots of hostas that nose their way above ground in late winter, so prevent them from being devoured with organic slug pellets, scattering them lightly around the crown. As they break down, these pellets give plants a boost by releasing iron and phosphate into the soil.
Hostas mainly originate from China, Korea and Japan, where they can be found growing in woodland, forest margins, mountains and alongside rivers. We’ve been growing them in Britain since 1790, when specimens of Hosta plantaginea and Hosta ventricosa were brought back from China.
Today, there are close to 2,000 different ones available in Britain. Sadly, none of them are slug-proof, but some seem to be more resistant to attack. Those with thick leaves or leaves coated in a shiny, waxy layer tend to remain unharmed, along with varieties that have blue leaves or a heavily corrugated surface.
Most varieties prefer consistently moist, but not boggy, fertile soil in semi-shade, making them perfect partners for ferns, heucheras and astilbes. Yellow leaved ones are happy in a lighter spot, so long as they have some protection from the scorching midday sun.
The foliage of mature hostas is irresistible to slugs and snails, so surround with a barrier, such as copper rings, sharp grit or a gel repellent. As plants develop during the season, older leaves will eventually touch the soil beyond defences, acting like a bridge. Beef up security with organic slug pellets.
Some gardeners swear by drenching hostas with water infused with crushed garlic cloves. According to advocates, essential oils from the pungent vegetable will repel any approaching slug or snail. Those who fancy putting it to the test will find lots of recipes online for garlic washes. Due to their compact nature, hostas are perfect in pots. Defend plants from invasion by raising them off the ground on pot feet and encircling the container with a band of copper tape.
BEGIN THE BATTLE WITH A PRE-EMPTIVE WINTER STRIKE