Herb · Asteraceae
Roman Chamomile
Chamaemelum nobile
Full sun and dry feet, and it spreads into a soft apple-scented mat.
Full sun
Every 7–10 days
60–90 days
USDA 4–9
Overview
Roman chamomile is a low, creeping perennial in the daisy family that knits itself into a dense mat. Its feathery foliage releases a warm, apple-like scent when you brush against it, which is why gardeners plant it for fragrant lawns and along path edges. The plant earns its keep through scent and flowers rather than height.
Through summer it carries simple white-and-yellow daisy flowers. For tea, gather the flower heads when the petals lie flat or have only just opened fully, then dry them. Timing the harvest to that stage gives you the best material before the blooms pass their peak.
This is an easy herb to keep once you match its conditions. It wants sun, fast-draining soil, and very little feeding, and it asks mainly that you keep its roots from sitting wet. Get those right and it spreads with little fuss.
Care
The short version: give Roman chamomile full sun and sharp drainage, water only when the top half of the soil has dried, and feed almost nothing. Soggy roots are what kill it fastest, so the whole approach centers on keeping the crown dry. Shear it back after bloom and you keep the mat dense.
Light
Site it in full sun for the best result, though it will accept partial shade. The reason to favor sun is structural: more light pushes a tighter, denser mat and a heavier flush of bloom. In shade the plant survives but grows looser and flowers less.
Water
Water moderately and let the top half of the soil dry out between drinks, which usually works out to every 7 to 10 days. Once it has settled in, the plant handles drought well. The hard rule is to avoid soggy soil, because saturated ground starves the roots of air and brings on root rot, the fastest way to kill this plant.
Soil
Give it light, well-drained sandy loam at pH 5.6 to 7.5. Drainage carries far more weight than the exact pH reading here, so if you garden on heavy clay, work in grit to open the soil and let water move through. Sharp drainage is the single condition this plant most depends on.
Temperature
It runs comfortably from 39°F to 86°F (4°C to 30°C) and is hardy down through zone 4, suiting zones 4 to 9. The limiting factor is summer: prolonged heat and humidity thins and browns the center of the mat as conditions there turn close and airless.
Humidity
Keep it on the dry side, somewhere around 30% to 50%. The risk in humid spells is fungal dieback that takes hold in muggy, still air. What protects the plant is movement, so airflow matters more than the moisture reading itself.
Feeding
Treat it as a light feeder and give little to no fertilizer. A single balanced, low-nitrogen feed in spring covers its needs for the year. Pushing more than that produces soft, sappy growth that aphids settle on, so restraint here is genuinely protective.
Pruning
After flowering, shear or mow it back lightly to hold the mat dense and trigger fresh growth from the base. Through the season, deadhead spent flowers to keep the bloom going longer. Both cuts work with the plant's habit rather than against it.
Repotting
It rarely needs repotting. For a container-grown plant, divide and refresh it every 2 to 3 years, or step in sooner if the roots start circling the pot, the growth thins out, or the soil drains so fast it dries almost at once. Those are the signals the plant has outgrown its space.
Size & spacing
Expect 6 to 12 inches (15 to 30 cm) in height and a spread of 12 to 18 inches (30 to 45 cm) as it mats outward. For a continuous lawn, space plants so they grow together and knit; for separate tidy clumps, leave gaps between them.
When to plant
The growing year follows soil temperature and bloom. Sow indoors in late winter to get a head start, move young plants out only after the last frost once the soil has warmed enough to drive root growth, then collect flower heads through summer as they open. Reading the season this way keeps each step in sync with the plant.
Northern hemisphere
Southern hemisphere
Typical months for a temperate climate: start earlier in warm zones, later where spring frosts linger.
- Sow: Late winter to early spring, 6-8 weeks before the last frost
- Plant: Spring, after the last frost when soil has warmed
- Harvest: White-and-yellow daisy flowers in summer; harvest flower heads when the petals are flat or just fully opened
Hardiness
USDA hardiness zones: 4–9
Temperature: down to -34°C
Troubleshooting
Most trouble with this plant traces back to two conditions: wet roots and stagnant, humid air. The problems below sort into pest pressure that follows soft growth and rot or dieback that follows poor drainage and weak airflow. Match the symptom to the cause and the fix is usually a change in the growing conditions, not a spray.
Wilting and yellowing collapse in wet soil
Plants wilt, yellow, and collapse while sitting in wet soil. This is root rot from poorly drained or overwatered ground, where the roots suffocate and turn black and mushy, and a plant that far gone cannot be saved. The response is to improve drainage and cut back on watering, then pull and discard the badly affected plants.
Fix:
- Improve soil drainage
- Reduce watering frequency
- Remove and discard severely affected plants
Center of the mat thins and browns
The center of the mat thins, browns, and dies out during hot, humid stretches. The driver is heat and humidity stress, sometimes paired with fungal dieback where air sits still. To recover it, shear back to bring on fresh basal growth, thin the planting for airflow, and give it afternoon shade in hot climates.
Fix:
- Shear back to encourage fresh basal growth
- Improve air circulation by thinning
- Provide afternoon shade in hot climates
Distorted sticky buds with clustered insects
Flower buds turn distorted and sticky, carry clusters of insects, and the plant flowers less. The cause is aphids on the developing buds, and excess nitrogen sets the stage by producing the soft growth they prefer. Confirm it by spotting small soft-bodied insects alongside shiny honeydew. Knock them back with a strong jet of water, follow with insecticidal soap, and encourage ladybugs; prevent it by easing off the fertilizer and keeping air moving.
Fix:
- Spray plants with a strong jet of water
- Apply insecticidal soap to affected buds
- Encourage beneficial predators such as ladybugs
Sticky curled foliage with insects underneath
Foliage goes sticky and curled with clusters of small insects on the undersides. That points to aphids feeding on the tender leaves, confirmed by finding the insects and honeydew under the foliage. Hose the leaves off, treat with insecticidal soap, and support beneficial insects and ladybugs to hold the population down.
Fix:
- Hose off foliage with water
- Apply insecticidal soap
Toxicity
The flowers brew a gentle soothing tea that is safe for most people, yet the plant earns a place on the ASPCA list as mildly toxic to cats, dogs, and horses. The reason sits in the foliage: volatile oils and anthemic acid can trigger vomiting, an itchy rash, and, with steady long-term chewing, a tendency to bleed. Enjoy the tea and keep grazing pets off the plant.
Toxic to
Cats · Dogs · Horses · Rabbits · Livestock · Birds
Safe for
People
Cats Mild
The ASPCA flags chamomile as mildly toxic to cats. A cat that nibbles it may drool, vomit, or go off its food, and the volatile oils can raise an itchy rash where the plant meets skin. The deeper concern is steady chewing over weeks, because anthemic acid can thin the blood and increase bleeding risk.
Dogs Mild
Dogs show much the same mild reaction: an upset stomach, loose stools, and poor appetite after a curious chew. Crushed foliage brushed against the skin can bring on contact dermatitis. Keep an eye on a dog that grazes day after day, since long-term exposure can lead to a bleeding tendency.
Horses Mild
Grazing horses come off lightly with mild digestive upset, a dull appetite, and the occasional skin reaction. A single mouthful poses no acute danger, but the same blood-thinning effect builds with chronic grazing, so keep horses clear of chamomile borders and pasture stands.
Rabbits Caution
Rabbits are not on the ASPCA list, yet the same volatile oils make this a poor choice for so small a grazer. One nibbled flower head is unlikely to do harm, but steady browsing could bring soft stools or appetite loss, so keep it out of reach.
Livestock Caution
Cattle, goats, and sheep usually leave the bitter, aromatic foliage alone, and a few mouthfuls rarely cause trouble. Still, treat it with caution, because the volatile oils and tannins that bother pets can irritate a grazing animal's gut if it eats a large amount.
Birds Caution
There is little solid data on birds either way. It is not known to be dangerous to them, but the irritant oils mean a pet bird should not graze it freely, and any deliberate herbal use is worth running past an avian vet first.
People Safe as tea
The flowers are the classic base for a calming cup of tea and are safe to drink for most people. The catch is the daisy family link: anyone allergic to ragweed or related plants can react, and handling fresh foliage sometimes leaves a mild skin rash.
Handling or crushing the foliage can cause contact dermatitis in sensitive people and animals; wash hands after handling and keep grazing or chewing pets away.
Helpline numbers
United States
ASPCA Animal Poison Control: (888) 426-4435 (fee applies)
United Kingdom
Animal PoisonLine: 01202 509000 (fee applies)
Australia
Animal Poisons Helpline: 1300 869 738
Varieties
Two named forms stand apart from the wild type and serve different purposes in the garden. One is grown for fragrant lawns and skips flowering entirely; the other is kept for its fuller, doubled blooms. Choose by whether you want a walkable carpet or a showier flower.
'Treneague'
'Treneague' is a non-flowering, low-growing form prized for fragrant chamomile lawns, and because it sets no seed it can only be increased by dividing the mat.
'Flore Pleno'
'Flore Pleno' is a double-flowered form that carries rounded, fuller blooms in creamy white rather than the plain single daisy.
How to propagate
Roman chamomile takes from seed or division, and both are straightforward. Seed gives you many plants at low cost, while division clones an established mat and is the only route for the non-flowering 'Treneague' that never sets seed. Pick the method that suits the form you are growing.
SeedEasy
Sow indoors in late winter to early spring, or direct-sow after the last frost · Germinates in about 10-14 days; establishes over the first growing season
Sow seed indoors from late winter to early spring, or direct-sow after the last frost. The seed is fine and needs light to germinate, so scatter it on the surface and press it down instead of burying it. Expect germination in about 10 to 14 days, with the plants settling in over their first growing season.
DivisionEasy
Spring or early autumn · 2-4 weeks to root in
Lift an established mat in spring or early autumn and split it into rooted clumps, which take hold within 2 to 4 weeks. Division is also the only way to propagate the non-flowering 'Treneague', since it never produces seed.
Myths
Roman chamomile and German chamomile are the same plant.
They look alike and both make tea, but they are different plants in different genera. Roman chamomile is a low, mat-forming perennial, while German chamomile is a taller annual that reseeds itself. One settles in as fragrant groundcover; the other shoots up and is gone by winter.
Chamomile is completely safe around pets because it is a soothing herbal tea.
Safe in a cup is not safe in the garden. The ASPCA lists chamomile as toxic to cats, dogs, and horses, and chewing it can bring vomiting, diarrhea, appetite loss, and an itchy rash. A herb that calms people can still make an animal sick.