Lily of the valley

Questions about lily of the valley

Does lily of the valley need sun or shade?

Lily of the valley grows in part shade (2 to 4 hours of sun, mostly in the morning) and shade (less than 2 hours of direct sun, or bright dappled light). It is one of the few that also put up with deep shade.

It wants soil that stays evenly moist, of average fertility, and a good soak in dry spells. Once settled in, it stands drought.

What zones does lily of the valley grow in?

USDA zones 3 to 7. It is hardy to zone 3, which means it survives winter nights down to about −30 °F (−34 °C).

Above zone 7 it struggles: the zones measure winter cold, but a plant's top zone usually means the summers are too hot or the winters too mild for it to rest.

Gardening in Canada? Use the USDA zone for your town: Canada's own zone map uses different numbers.

When does lily of the valley flower in my zone?

In zone 5 it flowers early May to late May. As a spring flower it moves about a week for every zone: earlier where it is warmer, later where it is colder.

Worked out from Hopkins' bioclimatic law: spring arrives about four days later for each degree of latitude north, and one zone is roughly two degrees. A warm spring or a cold one moves any garden two weeks either way.

How far apart should lily of the valley be planted?

8 in (20 cm) apart, from the middle of one plant to the middle of the next. That is a little closer than its full width of 12 in (30 cm), so a group knits into one patch.

It grows 8 in (20 cm) tall. Give it the full distance from anything taller, or it will lean out towards the light.

How many lily of the valley plants do I need?

At 8 in apart, set out in staggered rows:

• 27 to fill 10 square feet (about 1 m²)
• 16 for a single row 10 ft (3 m) long
• 86 to fill a 4 × 8 ft bed on its own

In a mixed border, plant it as threes and fives, along the front and just behind it.

In the bed above, the planner used 34 in eight groups.

Is lily of the valley poisonous to dogs and cats?

Yes: severe toxicity to people, dogs, cats and horses. All parts are highly poisonous if eaten and can affect the heart.

Rated from NC State Extension and the ASPCA. Where references disagree, the more cautious rating is used.

Is there a pet-safe plant like lily of the valley?

These come closest to doing what lily of the valley does, and no toxicity is recorded for them:

• Common blue violet: the same job in a bed, the same size and the same colour; flowers mid April to late May.
• Woodland stonecrop: the same job in a bed, the same flowering time and the same colour; 4 in shorter, fine leaves, not medium.
• Japanese pachysandra: the same job in a bed and the same size; grown for its leaves, not its flowers, keeps its leaves in winter.

Matched the way the planner's Swap button matches plants: the same job in a bed, then size, then flowering time.

Do deer eat lily of the valley?

Mostly not. NC State lists it as resistant to deer and rabbits. No plant is proof against a hungry deer in a hard winter, but this one is low on the menu.

Will lily of the valley spread?

It spreads sideways, by runners or roots; the risk of it taking over is high. Spreads aggressively by underground runners into dense colonies, and has escaped into woodland in parts of North America. Plant it only where it can be contained.

What flowers after lily of the valley?

Lily of the valley is over by late May. These start as it finishes and carry the same spot on, so it never goes flat:

• Lady's mantle: from late May to early July, 18 in tall.
• Astilbe: from late June to mid July, 24 in tall.
• Cranesbill 'Rozanne': from early June to early October, 18 in tall.

What does lily of the valley look like in winter?

Lily of the valley dies down to the ground and there is nothing to see until spring. The old stems can be cut in autumn, or left until spring as shelter for overwintering insects.