Daylily
One of the most forgiving perennials there is — clumps of arching leaves and a long relay of trumpet flowers, each lasting a single day. Thrives on neglect in almost any soil. But it shares the lily's deadliest secret, and cat owners need to know it.
Lethal to cats — as dangerous as a true lily
Despite the name, a daylily isn't a Lilium — but it is just as deadly to cats. Hemerocallis causes the same acute kidney failure; the ASPCA notes cats are the only species affected, with vomiting, lethargy and possible death. There's no antidote and the window to act is short (around 18 hours). If you own a cat, don't grow daylilies where it roams and never put them in a bouquet indoors. Dogs and horses are not affected. Source: ASPCA.
Care at a glance
Everything that matters, in six lines. The detail is further down.
Position
Most flower best in full sun; they tolerate light shade with fewer blooms. Genuinely unfussy.
Soil
Clay, sand, damp, dry — daylilies cope. Improved, moisture-retentive soil simply gives more flowers.
Water
Water new plants their first summer; established clumps are drought-tough and rarely need it.
Feeding
Compost or well-rotted manure in spring is plenty. Overfeeding gives leaves at the flowers' expense.
Aftercare
Snap off spent blooms for neatness; cut old foliage back once it collapses in late autumn.
Hardiness
Bone-hardy across Britain. Dies down in winter and returns reliably every spring.
What to do, and when
Fresh leaves push up early. Mulch around the clump, and divide congested plants now with a spade if flowering has thinned.
The long flowering relay — each bloom lasts a day, the clump for weeks. Deadhead for tidiness; water only in real drought.
Flowering ends and foliage yellows. Cut it back once it flops. A good time to plant or move divisions.
Fully dormant, nothing to do. The crowns sit out the cold untroubled.
The name that misleads — and the danger that doesn't change
A daylily is not botanically a lily at all; it's Hemerocallis, a different family entirely. Gardeners cling to the 'it's not a real lily' point — but for cats it makes no difference whatsoever. Daylilies cause exactly the same fatal kidney failure as true lilies, from exactly as small a dose.
This is precisely why we record safety by species and not by common name. 'Not a true lily' is reassuring and, for cats, completely wrong. If you have a cat, treat daylilies with the same seriousness as Lilium: not in the house as cut flowers, not where the cat roams, and any contact is a same-day vet call.
Why it's the easiest perennial to grow
In a cat-free garden, daylilies are close to indestructible. They grow in sun or part shade, in heavy clay or dry banks, and shrug off drought once established. A single plant becomes a weed-smothering clump in a couple of years and can be sliced into divisions with a spade to fill a border for nothing.
There's almost no maintenance: a spring mulch, deadheading if you like things tidy, and a cut-back in late autumn. That's the whole year.
Common problems
Lots of leaves, few flowers
Too much shade or too rich a soil. Move to more sun; skip the feeding, just mulch.
Clump flowering less over time
Congested crown. Lift and divide in spring or autumn — every piece regrows.
Chewed, ragged new leaves
Slugs on the spring growth. Usually cosmetic on such a vigorous plant; clear debris around the crown.
Rusty orange spots on leaves
Daylily rust, mostly cosmetic. Remove badly affected leaves; it rarely troubles the plant's vigour.
Everything a daylily needs
Barely anything — this is a plant that multiplies itself for free.
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If you like this, try
Other plants with a similar temperament.
From the Notebook
Seasonal notes and guides that mention the daylily.
How we checked this
Care guidance cross-checked against the Royal Horticultural Society and NC State Extension. Toxicity confirmed against the ASPCA database, which lists the daylily (Hemerocallis) as toxic to cats only — vomiting, inappetence, lethargy, kidney failure and possible death. If our page and the ASPCA ever disagree, believe them and tell us. If our page and these sources ever disagree, believe them — and tell us.
Sources: RHS · NC State Extension · ASPCA
Last reviewed · July 2026