Ornamental · Brassicaceae
Candytuft
Iberis sempervirens
Hand it full sun and soil that drains and candytuft spills a sheet of white flowers all over the spring garden.
Full sun
Every 7–10 days
USDA 3–8
6–12 in · 15–30 cm
Overview
Candytuft is an evergreen perennial that hugs the ground and then bursts into bloom every spring. It's actually a member of the cabbage family, and its low, woody mat of narrow dark leaves stays green right through winter if your zone isn't too harsh. Then April rolls around and the whole mat pretty much disappears under a blanket of small white flowers that the early bees love.
Think of it as a plant for the edge of a bed, the top of a wall, or a rock garden, where it'll tumble over stone and knit itself into a neat carpet 6 to 12 inches tall. It's tougher than it looks too, brushing off cold down to zone 3 and dry spells once it's rooted in. The one thing it won't put up with? Wet, heavy soil sitting around the crown.
So care really boils down to a sunny spot, ground that drains fast, and a quick trim after the flowers fade. Do that and one plant will stick with you for years, slowly filling out into a tidy evergreen mound that still looks good long after the bloom's done.
Care
The short version: full sun and fast-draining soil are everything, go easy on the watering once it's settled in, and shear it back by about a third the minute it stops flowering.
Light
Candytuft flowers best in full sun, which keeps the mat dense and the blooms thick. It'll handle partial shade, sure, but it grows looser there and you'll get fewer flowers, so a bright spot's the way to go.
Water
Once it's established, this one's drought-tolerant and likes to dry out between drinks, so there's no need to hover over it. Let the top half of the soil dry out, then water every 7 to 10 days at the most. The quickest way to kill it is soggy soil, which rots the crown, so lean dry.
Soil
Sharp drainage matters more than anything else here. Candytuft isn't fussy about texture and takes clay, loam, or sand just fine, and it leans toward a neutral to alkaline pH of 6.0 to 8.0. What it really can't stand is ground that stays wet.
Temperature
This is a seriously hardy perennial, happy from a brutal -40°F (-40°C) all the way up to around 90°F (32°C). And the evergreen foliage just carries on through winter across its range, no help needed from you.
Humidity
Plain old garden air works fine, so there's no humidity number to chase. What actually matters is air movement, since still, damp air is what invites mildew onto the leaves.
Feeding
Candytuft's a light feeder that barely asks for anything. One dose of slow-release general fertilizer in early spring carries it through the whole season, and feeding it more than that just gives you soft, floppy growth.
Pruning
The one job that keeps it looking sharp is a trim after it blooms. Cut the stems back by about one-third as soon as the flowers fade, and that holds the compact shape while pushing out fresh new growth.
Repotting
Candytuft hardly ever needs repotting, and it doesn't love being messed with. Keep an eye out for roots circling the drainage holes or soil that dries out almost as fast as you water it, and only then bump it up a pot size.
Size & spacing
Plants stay low at 6 to 12 inches (15 to 30 cm) tall and spread to about 12 to 18 inches (30 to 45 cm) wide. Space them that far apart so air can move between the mounds and the foliage stays nice and dry.
When to plant
Candytuft runs on the spring calendar, so it's easy to keep track of. Start seed indoors in late winter, set plants out once hard frost's done or in early fall, and the white flowers show up from April into May, sometimes hanging on into early summer.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Late winter, about 6-8 weeks before the last spring frost
- Plant: Spring after danger of hard frost has passed, or in early fall
- Harvest: Early to late spring (April to May), sometimes into early summer
Hardiness
USDA hardiness zones: 3–8
Temperature: down to -40°C
Troubleshooting
Candytuft's an easy plant, and just about every problem it runs into comes back to too much water or stale air. The good thing is you'll see it early on the crown and leaves, so you can jump in before it spreads. Find the one that matches below, then deal with it while it still does some good.
Plant flops over with a brown, rotting crown
If the whole thing flops and the crown goes brown and mushy, that's crown and root rot, and it's really the one thing that kills candytuft. It isn't a disease you spray, it's just wet feet, so soggy soil chokes the base, the stems turn soft at the soil line, and the plant pulls right out with black roots. Want it to bounce back? Toss anything badly rotted, work in some grit or build a raised bed, and then replant.
Fix:
- Remove and destroy severely affected plants
- Improve drainage by amending soil with organic matter or planting on a slope or raised bed
- Reduce watering and avoid wetting the crown
Dusty white film or spots on the leaves
A dusty white coating on the leaves is usually powdery or downy mildew, and if you're seeing spots or rusty bumps instead, that's a fungal leaf problem. Both like the same thing, which is still air and leaves that stay damp. The fix is easy: pull off the marked leaves, give the plants some elbow room at 12 to 18 inches apart, and water down low so the foliage dries off quickly.
Fix:
- Remove and dispose of affected foliage
- Improve air circulation by spacing plants 12-18 inches apart
- Avoid overhead watering and water at the base
Ragged holes chewed in the leaves and flowers
Those ragged holes that turn up after a rainy patch? That's slugs and snails doing the chewing, and sometimes a caterpillar joins the party too. You'll spot the slime trails and the damage that shows up overnight. So head out after dark and pick them off, set out a bait or trap if that's easier, and rake away the damp mulch and leaf litter they hide under all day.
Fix:
- Handpick slugs, snails, or caterpillars
- Use slug baits or traps where appropriate
- Remove debris and mulch that harbors slugs near plants
Toxicity
Here's the good news if you've got pets or kids around: candytuft isn't toxic. The ASPCA doesn't list it as a harmful plant, and the extension and botanical sources all back that up, so there are no poisoning worries. A stray nibble or a flattened patch won't hurt anyone, which makes it a safe pick for any family garden.
Safe for
People · Cats · Dogs · Horses · Rabbits · Livestock · Birds
Cats None
If the cat sneaks a nibble, that's fine, because candytuft isn't on the ASPCA toxic list and there's nothing here to hurt it.
Dogs None
The dog can sniff it, chew it, or flatten the leafy mat all it wants, and there's no poisoning risk at all.
Horses Safe
Got horses nearby? No problem, since this plant doesn't carry anything known to harm them.
Rabbits Safe
Rabbits can nibble away at the low groundcover, and there's no part of it that's toxic.
Livestock Safe
Cattle, goats, and sheep are all fine if they wander into a patch, with no poisoning risk to speak of.
Birds Safe
Garden birds and backyard chickens can peck around candytuft without any harm coming to them.
People Safe
It's totally safe to handle and fine to have around kids, though it's grown to look at rather than to eat.
No special handling precautions are required; routine gardening hygiene such as washing hands after contact is sufficient.
Varieties
Most garden candytuft is sold by cultivar, and honestly they mostly just differ in size and how heavily they bloom. Here are the ones worth knowing by name.
Snowflake
It's a strong grower with wide leaves and big, packed clusters of pure white flowers.
Purity
It's a compact, hardworking bloomer that throws out sheets of bright white flowers in spring.
Alexander's White
It's a low, tidy mound covered in white flowers, and it makes a really clean edging plant.
Little Gem
It's a little dwarf at just 6 to 8 inches tall, so it's great for pots and tight little corners.
How to propagate
Candytuft's easiest to multiply from cuttings or seed, because that thin main root makes the usual perennial move of splitting a clump pretty hit-or-miss.
Stem cuttingsEasy
Early to midsummer, right after flowering has finished · A few weeks to root, then transplant once established
Cuttings are honestly the surest way to make more candytuft. Once the flowers fade in early to midsummer, snip off pieces about 6 inches long and tuck them into a moist, gritty mix like sand or vermiculite. Give it a few weeks and they'll root, and then they're ready to move wherever you want them.
SeedEasy
Sow indoors in late winter or outdoors in spring · Germinates in a couple of weeks; blooms typically the following season
Seed is the easy route, just a slow one. Sow it indoors in late winter or right into the ground in spring, and you'll see seedlings within a couple of weeks, though they usually hold off blooming until the next season. Leave a few faded flowers behind and the plant will just sow itself for you.
DivisionModerate
Early spring or fall · Several weeks; success is variable
Division is the least reliable way to go here, so don't count on it. Dig up a clump in early spring or fall and pull it apart so each piece keeps its roots and some good stems, but don't be surprised if the results are spotty, since that thin main root really doesn't like being cut. It takes a few weeks to settle either way.
Myths
Candytuft is easily divided like most spreading perennials.
Here's the catch: it grows from a thin main root over a woody base, so splitting it is a gamble and a lot of the divisions just won't take. Stem cuttings after it flowers, or a packet of fresh seed, give you way better odds of ending up with new plants.