How to Grow Chamomile in Australia

Chamomile is the name shared by two herbs in the daisy family, Asteraceae, both grown for small white flowers with golden centres. German chamomile (Matricaria recutita) is an upright annual whose flowers are traditionally dried for tea, and Roman chamomile (Chamaemelum nobile) is a low, apple-scented perennial. Golden chamomile 'Kelwayi' (Anthemis tinctoria) is a yellow dye daisy, not a tea chamomile. The step most growers get wrong comes first: the seed needs light, so it is pressed onto the soil and never buried.

Three mistakes that matter

1. Burying the seed. Chamomile seed is tiny and needs light to germinate, so seed covered with soil often fails to come up. Scatter it on the surface and press it in, as Sowing Seeds describes.
2. Sowing into summer heat. Chamomile prefers mild weather, and plants sown into hot weather in warm zones often struggle and flower only briefly. In the tropics and subtropics, sow from autumn into winter, as When to plant sets out.
3. Growing it too rich. Rich soil and heavy feeding give tall, floppy plants with fewer flowers. Grow chamomile in lean, free-draining soil and feed only seedlings, lightly, as Care by growth stage shows.

When to plant

Mild weather, more than a soil temperature, sets the season for chamomile. Seed comes up in 7 to 14 days in soil of about 20 to 30°C, and Roman chamomile germinates in soil from about 12°C. German chamomile is a hardy annual, so autumn sowings can overwinter as small plants, while summer heat cuts plants short. In temperate gardens, a sowing around Anzac Day gives flowers in spring. The harvest months below are for German chamomile; Roman chamomile takes longer to flower, as Sowing Seeds shows.

Where frost lingers, start seed under cover four to eight weeks before planting out. In hot inland and western areas, sow at the cooler edges of each window, because plants struggle once summer heat arrives.

Site, soil and setup

Chamomile is at home in cool climates, and has been trialled as a commercial crop in Tasmania.

Container growing

A pot at least 30 cm across, holding about 13.5 L, suits German chamomile, with plants 15 to 20 cm apart in quality potting mix. Roman chamomile makes a low, spreading cover in a wide bowl or trough. Golden chamomile 'Kelwayi' grows too tall for most pots.

• Water: check pots daily in warm weather, because they dry out faster than beds.
• Feed: fish and seaweed blend at half strength, about 12 mL per 9 L, fortnightly once flowering starts.
• Position: full sun, moving pots into afternoon shade during heatwaves.

Sowing Seeds

Sow chamomile direct where it is to grow, or raise it in trays and plant it out young.

Sowing direct

• Mix the seed with fine sand so it spreads evenly, as sowing tiny seeds shows.
• Scatter it over moist soil and press it in firmly without covering it.
• Mist daily so the surface stays damp until seedlings appear, usually in 7 to 14 days.
• Thin to 20 cm apart once seedlings are about 5 cm tall.

Starting under cover

• Sow onto seed raising mix in trays or cells, and leave the seed uncovered.
• Keep the tray bright and the mix just moist, watering with a fine mist as watering seeds and seedlings explains.
• Plant out while seedlings are 2.5 to 5 cm tall with three or four true leaves.
• Harden off first (gradually accustom seedlings to sun and wind), as hardening off seedlings describes.
• Space German chamomile 20 cm apart, and Roman chamomile 10 cm apart for a lawn.

Care by growth stage

Even moisture while young and restraint with feeding decide how well chamomile flowers. Once plants are established, water at the base in the morning when the soil is dry 2 to 5 cm down.

Keep every feed at half strength. If growth stalls in very poor soil, a light dose of all-purpose controlled release granular (NPK around 14-5-10) scratched in around the plants can help. A light mulch holds moisture and keeps weeds down.

Deadheading

Picking is the deadheading for German chamomile, as Harvesting Flowers describes. Clipping keeps Roman chamomile dense, and removing spent flowers lengthens the Golden chamomile show.

• German chamomile: trim straggly stems to keep plants compact and bushy.
• Seed for next year: leave a few German chamomile heads to dry on the plant late in the season.
• Roman chamomile lawn: mow or clip it regularly to keep it thick and remove old flower stems.
• Roman chamomile in beds: cut back lightly after flowering to neaten plants and bring on new growth.
• Golden chamomile 'Kelwayi': cut off spent flowers to keep blooms coming from summer into autumn.
• Near bushland or paddocks: deadhead before seed drops, because all three self-seed.

Companion planting

Chamomile flowers draw hoverflies and other small beneficial insects, which makes it a useful edging for the vegie patch.

Grows well with

• Cabbages and other brassicas, whose aphids feed the hoverflies that chamomile draws.
• Fruit trees, where a chamomile understorey brings beneficial insects into the orchard.

Keep apart

• Mint, whose invasive roots take over and swamp a plant that competes poorly.
• Sweet corn and other tall summer crops, which shade a plant that flowers best in full sun.

Harvesting Flowers

Pick each flower once its white petals are fully open and lying flat, before they fold back from the centre.

• Pick on a dry, warm morning.
• Pinch each head off just below the flower, or rake your fingers through the plants and pull the heads off gently.
• Pick every few days, because regular picking brings on more buds and a second flush.
• Pick Roman chamomile flowers the same way.
• Keep Golden chamomile out of the tea harvest, and cut its flowers for vases or dyeing.

Dry picked flowers for one to two weeks in a single layer on a rack or tray, somewhere warm, airy and out of direct sun. Store them fully dry in an airtight glass jar in a cool, dark place, where they keep for 6 to 12 months.

The flowers are used fresh or dried, and both German and Roman chamomile are traditionally infused as a tea.

Common problems

No seedlings appear. Besides buried seed (see Three mistakes that matter), a surface that dries out while seed is germinating can kill it, so mist daily. Read more

Seedlings collapse at soil level. Damping off, a soil-borne rot of young seedlings, strikes in cold, wet mix, so use free-draining mix and water with a fine mist. Read more

A chamomile lawn turns patchy. Roman chamomile is less hardy than lawn grass, so regular foot traffic and weeds thin it out. Weed it by hand and route foot traffic around it.

Dried flowers turn mouldy or musty. Flowers stored before they are fully dry, or kept in light and warmth, spoil. Dry them until crisp, store them airtight in the dark, and throw out any that turn mouldy.

Pests and diseases

Chamomile is seldom badly troubled, but snails take seedlings and sap-sucking insects gather on its soft tips and flowers.

Garden snail (Cornu aspersum) and slugs. They chew soft seedlings after dark, most of all on wet nights, and a surface-sown patch is easy prey. Hunt them by torchlight while seedlings are small. Read more

Aphids (family Aphididae). These small sap-suckers cluster on soft new growth, leaving it malformed and sticky with honeydew. Squash small colonies by hand or hose them off, and let hoverflies and ladybirds deal with the rest. Read more

Thrips (order Thysanoptera). Only 1 to 2 mm long, thrips leave silvery-brown speckling and streaks on leaves. Rinse leaves, undersides included, or spray insecticidal soap weekly for four to six weeks to catch each new hatch. Follow the label, and wait out its withholding period before picking flowers for tea. Read more

Powdery mildew (several related fungi, order Erysiphales). Tiny white spots spread into a powdery white coat, worst low down in humid, sheltered growth. Remove affected leaves and spray 1 part full-cream milk to 10 parts water. Read more

Prevention first

• Space plants 20 cm apart so air moves between them.
• Water at the base in the morning so leaves dry before night.
• Check soft tips and the undersides of leaves weekly for aphids and thrips.
• Let hoverflies, ladybirds and lacewings work, and avoid broad sprays that kill them.

Tips

1. A Roman chamomile lawn takes about 100 plants per square metre, so start small. Stay off it for three months while it establishes.
2. Divide an established Roman chamomile clump in autumn or spring to fill gaps in a lawn or edging.
3. Chamomile has been linked with contact allergy in gardeners, and people allergic to daisy-family pollen can react to it. Wear gloves if your skin reacts. Chamomile is best avoided in pregnancy and can raise the risk of bleeding with warfarin. Ask a doctor or pharmacist before using any home-grown herb.
4. Chamomile is listed as toxic to dogs, cats and horses, so keep it away from pets and stock that graze garden plants.