Sun or shade: where to plant hostas

Hostas have a reputation as shade plants, and it is well earned: they are among the best plants for the darker parts of a garden. But "shade" covers everything from a bright spot under a light tree to the dark side of a wall, and how much sun a hosta can take depends a great deal on its leaf colour. This guide helps you match the plant to the light you actually have.

Do hostas like sun or shade?

Shade, mostly. Iowa State University names full or partial shade as the best site for hostas, and in gardens most of them do best in partial shade: a few hours of sun early in the day and shade through the hottest hours. Many varieties also grow in deeper shade, and a few cope with a fair amount of sun, but the RHS is clear that a hot, sunny spot with dry soil does not suit them.

Two things decide how much sun a hosta can take: the colour of its leaves and how moist its soil stays. A blue or white-centred hosta in a dry, sunny spot will scorch; a gold, sun-tolerant one in moist soil may thrive there.

How much sun does each type of hosta take?

The experts agree on the pattern. The RHS gives blue hostas light shade and lets yellow ones have some sun. Iowa State puts blue varieties in dense shade, gold ones in partial sun and variegated ones in shade, so that they do not scorch, and University of Missouri Extension notes that green and yellow hostas take more sun than the rest. Our product pages follow the same lines:

The light advice in the table comes from the "Light" line on each product page. Our sun-tolerant hostas are the varieties rated for the brightest spots, and our yellow and gold hostas are the ones that most need a little sun to colour well.

Morning sun or afternoon sun?

Morning sun, every time. University of Missouri Extension says most hostas like a few hours of morning sun followed by shade or filtered light in the afternoon, and Walters Gardens, a wholesale perennial grower, calls hot afternoon sun usually harmful to them. Early sun is gentler and the air cooler, so leaves take it without damage; afternoon sun arrives when the air is warmest and the soil driest, and that is when hosta leaves scorch.

How many hours count as partial shade? Walters defines it as 4–6 hours of direct sun a day, and anything under 4 hours as full shade. Iowa State gives the same 4–6 hours as the amount of partial sun that brings out the colour of gold hostas. For most hostas, those hours should come before midday.

To find out what you have, watch the spot on a sunny day in early summer, once the trees are in leaf. Note when direct sun first reaches it and when it leaves. Sun that comes early and is gone by lunchtime suits almost any hosta; sun from early afternoon onwards calls for a sun-tolerant variety. Dappled shade, the moving light under a tree with an open canopy, is close to ideal: the leaves get light all day without long spells of direct sun.

If your garden only has afternoon sun, choose a sun-tolerant variety, keep the soil moist and give it a thick mulch, or grow your hostas in pots that you can move into shade for the summer. Our guide to hostas in pots explains how.

Reading your garden: north, east, south and west

• North-facing beds and the north side of walls get little direct sun. They suit blue, white-centred and green hostas; gold varieties grow there too, but their colour is less bright.
• East-facing beds get morning sun and afternoon shade, the ideal combination for most hostas, gold ones included.
• West-facing beds get the hottest afternoon sun. Plant only sun-tolerant varieties there, in soil that stays moist.
• South-facing beds in full sun are the hardest. If you want hostas there, use the shade of taller plants or a tree, or choose the most sun-tolerant varieties and water well.

Trees change the picture through the year. Under a deciduous tree a hosta gets spring sun before the canopy closes and shade in summer, which many hostas like. Dense evergreens give deep, dry shade instead, which is a harder place for any plant.

Can hostas grow in full sun?

Some can, with conditions. Varieties rated for partial shade to sun, such as Liberty, Sunny Halcyon, August Moon and the fragrant So Sweet, handle much more light than a typical hosta. The condition is moisture. The RHS stresses that even sun-tolerant hostas need moist soil, Iowa State adds that plain green hostas can sometimes take full sun if they have enough water, and South Dakota State University goes as far as saying that leaf scorch has more to do with water movement in the plant than with direct sun. Dig in plenty of compost, mulch the bed and water deeply in dry spells.

Scent and sun often go together. The Hosta Helper website traces fragrant hostas back to Hosta plantaginea, and NC State University calls that species the most heat- and sun-tolerant of all hostas. Several of our fragrant varieties are rated for partial shade to sun, among them So Sweet, Fragrant Bouquet, Invincible and Plantaginea Grandiflora, a form of the species itself. More are in our fragrant hostas.

Which hostas are best for a sunnier spot?

These varieties from our range are all rated for partial shade to sun. Size and leaf colour are as listed on each product page.

Our product pages set the three giants among them, Liberty, Sagae and Sum and Substance, one condition for a sunnier position: soil that never dries out. For a small sunny bed or a pot, So Sweet and Invincible are easier to keep moist.

How to look after a hosta in a sunnier spot

1. Improve the soil before planting. Work a good layer of garden compost or rotted manure into the planting area, so the ground stays damp for longer.
2. Mulch every spring. A layer of bark or compost keeps the roots cool and slows evaporation.
3. Water deeply, not often. A thorough soaking at the base whenever the soil is dry a few centimetres down does more than a daily sprinkle over the leaves.
4. Water in the morning. The plant goes into the hottest part of the day with moist soil, and the leaves dry quickly.
5. Watch the first summer closely. A newly planted division has a small root system and dries out faster than an established clump.

Signs that a hosta gets too much sun

• Brown, crisp edges or patches, usually after a hot spell. Scorch starts at the leaf edges, South Dakota State University notes.
• Pale, bleached patches on leaves that should be green or blue, which Iowa State lists alongside brown edges.
• Blue leaves turning green early, because sun and heat strip the waxy coating.
• White or cream parts burning first. According to the Hosta Helper, scorch is worst at the margins and in the variegated parts of a leaf.

Scorched leaves do not recover. SDSU says the damaged parts stay damaged but the plant does not die, and advises leaving the leaves in place until new ones have grown. The RHS's remedy for scorch is a shadier spot: move the plant in early spring, before the leaves unfold. Brown edges can also mean the plant is simply too dry, so check the soil before you blame the sun.

Can hostas grow in deep shade?

Yes. Hostas are one of the few groups of plants that still look good in real shade, and blue, green and white-centred varieties are the best choice there. Gold and yellow varieties grow too, but their colour is duller without some sun. In very dark, dry places such as under conifers, the problem is usually water rather than light: hostas under trees compete with the roots for every drop. Our guide to hostas under trees covers that situation, and our planting and care guide explains how to prepare the soil.

White-centred and blue varieties are the natural choice for the darkest corners: see our white and cream hostas for pale leaves that light up deep shade.

Common mistakes

• Planting a blue or white-centred hosta in afternoon sun because the label said "partial shade".
• Choosing a sun-tolerant variety and then letting its soil dry out.
• Judging a spot in spring, before trees come into leaf and the shade pattern changes.
• Blaming the sun for brown edges when the real cause is dry soil.
• Expecting a gold hosta to stay bright gold in deep shade.

In short

• Watch your spot through a sunny day before you choose a variety.
• Give most hostas morning sun and afternoon shade.
• Put blue and white-centred hostas in the shadiest places, gold ones where they get a little sun.
• For a sunny bed, choose a variety rated for partial shade to sun and never let its soil dry out.