Hosta

1. 1

   Pick by leaf colour, size, and slug-resistance

   Blue-leaved varieties are the slug-resistant heroes — waxy bloom on the leaves makes them harder to eat. Halcyon (60 cm, classic mid-blue), Krossa Regal (1 m tall, blue-green vase shape), Sum and Substance (massive yellow-gold, 1.2 m wide, vigorous and slug-resistant). Gold/yellow-leaved: Sum and Substance (lime-gold), August Moon (bright gold) — vivid colour in shady corners. Variegated: Patriot (green with white margin), Francee (deep green with crisp white edge), Frances Williams (blue-green with cream margins). Most variegated hostas attract more slug attention than blue-leaved. Small / front of border: Blue Mouse Ears (15 cm tiny blue), Mighty Mouse. For a first hosta in slug country: Halcyon or Sum and Substance.

2. 2

   Plant in part to full shade

   Hostas are shade specialists. Most prefer dappled shade under deciduous trees, part shade (3–4 hours morning sun), or deep shade (under conifers, north-facing positions). A few cultivars tolerate more sun — the yellow-gold types (August Moon, Sum and Substance) colour better with 3–4 hours direct sun. Full sun on a hosta scorches the leaves brown at the edges by July — avoid.

3. 3

   Plant in moisture-retentive soil

   Hostas want deep, fertile, moisture-retentive soil enriched with leaf-mould or garden compost. They tolerate clay (better than most perennials), but dislike thin sandy soils that dry out. Plant in spring (March–May) or early autumn (September), so roots establish before extreme conditions. Spacing 60–100 cm depending on cultivar size — hostas need room to develop their architectural form.

4. 4

   Apply slug control before leaves emerge

   The single most important hosta husbandry. Slugs and snails strip emerging hosta leaves in March–April, ruining the plant before it's fully open. Apply slug control BEFORE growth starts (late February–early March). Four UK-effective controls: (1) Wool pellets scattered around the base — slugs dislike crossing the rough fibres; effective and organic. (2) Sharp grit / crushed eggshells as a 5 cm mulch around the crown. (3) Nematodes (Phasmarhabditis hermaphrodita) watered into the soil from March — biological control, very effective for 6 weeks. (4) Copper rings or tape around individual plants in pots.

5. 5

   Mulch generously each spring

   A 5 cm mulch of garden compost or leaf-mould around the crown each spring conserves moisture, suppresses weeds, and gradually improves the soil. Keep the mulch 5 cm clear of the emerging crown (don't smother the new shoots). Combine the mulch with slug control (wool pellets, grit) for double effect.

6. 6

   Water through dry spells

   Hostas wilt dramatically and shed leaves in summer drought. A deep weekly soaking in dry weather keeps the foliage in good condition. Pot-grown hostas need daily watering in summer. Yellow leaves at the base mid-summer = drought stress; the plant returns next spring but loses display this season.

7. 7

   Cut flower stems off (or let them flower)

   Hostas produce tall stems of tubular lavender, purple, or white flowers in July–August. Some gardeners cut the flower stems off as buds form — the plant focuses energy on foliage instead of flowers, leaves stay larger and more intense. Others let them flower — bees enjoy the trumpets, and the white-flowered species (Royal Standard, Honeybells) are evening-scented. Personal preference; both approaches work.

8. 8

   Cut foliage down after frost

   Late October–November, after the first hard frost has blackened the leaves, cut all foliage to 5 cm above the ground. Clear away the dead leaves to remove slug egg-laying habitat — leaving rotting hosta foliage in place is the easiest way to build a thriving slug population over winter. Compost the leaves elsewhere in the garden.

Slugs and snails devour hostas relentlessly; vine weevil also attacks roots.