Vietnamese coriander

Vietnamese coriander: how do you recognise it?

Habit

Low, creeping to upright herb, 30–40 cm tall and up to 50 cm wide, with stems that root at the nodes.

Leaves

Lance-shaped, 5–10 cm long, green and often with a dark, V-shaped mark; the stems are flushed red-brown.

Flavour and scent

Peppery, with notes of coriander, lemon and pepper. The leaves smell strongly when rubbed.

Flower

Small pink-white spikes. In Belgium the plant rarely or never flowers.

Roots

Thin and fibrous; the plant roots wherever a stem touches moist soil.

Harvest and fruit: June–September · Plants: May–June · Pruning: April and September

Why grow it?

• The leaves add a fresh, peppery flavour to soups, salads and stir-fries all summer long.
• It does not run to seed in summer, as ordinary coriander does.
• It grows well in damp, half-shaded spots where other herbs struggle.
• Pretty foliage with a dark pattern, also good in a pot or hanging basket.
• Easy to propagate: a stem in a glass of water roots by itself.

Vietnamese coriander: where does it grow best?

• Half shade is ideal: in full sun the leaves scorch quickly unless the soil stays wet.
• Humus-rich, loose soil (sand or loam), acid to neutral.
• Keep the soil constantly moist: the plant likes damp to wet places, for example beside a pond.
• Grow it in a pot or tub so that you can easily bring it indoors.
• Leave 40–50 cm between plants: they spread.

Light

Sun and partial shade

Soil type

Sand or loam

Acidity

Acid or neutral

Moisture

Wet

Size

0.4 m tall, 0.5 m wide

Hardiness

Frost tender: overwinter indoors (above 3 °C)

Goes well with

• Lemongrass: The same warm, damp position and a good Asian herb combination in a pot.
• Thai basil: Goes into the same dishes and likes warmth.
• Mint: Also likes moist soil and half shade; keep it in a separate pot, as mint spreads.
• Chilli pepper: Same season and same cuisine: grow them together in a sunny container.

Vietnamese coriander: when and how to plant it?

Plant in May–June.

1. Plant after the Ice Saints, in May–June, when night frosts are over and it is warm.
2. Choose a pot at least 25 cm across with drainage holes, or dig a hole in the border twice as wide as the root ball.
3. Mix potting compost or the soil you dug out with a few spadefuls of garden compost, so that it holds moisture.
4. Set the plant at the same depth as in its pot and firm the soil.
5. Water in generously straight away and add a mulch of compost or bark around the base.

Care

Water

Keep the soil moist all summer; dry soil makes the leaves tough and bitter. Check pots daily.

Feeding

Every 3–4 weeks, an organic or liquid feed during the growing season, so that there is always young foliage.

Harvesting

Cut stems of 10–15 cm regularly, just above a node. Young leaves taste best; use them fresh.

Mulching

A thin layer of compost or bark keeps the soil cool and damp.

In the kitchen

Raw in salads and herb mixes, or added at the end to soups and noodles, as cooking weakens the flavour.

Tip: Put a stem in a glass of water on the windowsill: it is the easiest way to overwinter it. In dry spells the leaves turn tough, so keep the soil constantly moist.

Vietnamese coriander: when to prune it?

Pruning months: April and September.

When: In April, when the plant starts into growth, and in September, before you bring it indoors.

How:

• In April, cut long, bare stems back to 10 cm above the soil.
• During summer, pinch out the tips regularly: this keeps the plant dense and compact.
• In September, cut the plant back by about half before it goes indoors.
• Use the trimmed tips in the kitchen or as cuttings.

Caution: In a warm, wet spot it grows fast and creeps on: keep it in a pot if you do not want it to spread through the border.

Pruning: when and how · Pruning calendar and basic rules

Propagation

Cuttings in water

All season: a stem of 10–15 cm with the lower leaves removed, in a glass of water in a bright place. Roots appear in 1–2 weeks; then pot up.

Rooted runners

In spring, detach a rooted stem from the mother plant and plant it separately.

Vietnamese coriander: how does it get through the winter?

Hardy to 3 °C: protect in harsh winters.

• Not hardy: the plant needs at least 3 °C and suffers even in light cold.
• Bring it in during September–October, to a bright spot by a window at 10–15 °C or into a room.
• Water sparingly, but do not let the root ball dry out completely. Do not feed until spring.
• To be safe, take a few cuttings in summer and root them indoors in water or potting compost.

Diseases and pests

• Red spider mite: Fine webs and dull, speckled leaves in dry indoor air. Mist regularly and rinse the plant with water.
• Aphids: Sticky young tips. Rinse off with water or wipe the plant; ladybirds often help.
• Slugs: In the garden they love young shoots. Collect them or put up a barrier; in a pot they are easier to keep away.
• Limp or yellow leaves: Usually too dry or too cold. Water and move to a warmer spot; if the roots are sitting wet, water less.

Through the year

• January: Overwintering indoors in a bright spot. Water sparingly.
• February: Indoors. Check for red spider mite and aphids.
• March: Take cuttings in water and root them on a warm windowsill.
• April: Cut back long stems. Repot in fresh compost.
• May: After the Ice Saints, put outside or plant in a damp, half-shaded place.
• June: Start harvesting. Pinch out tips for a dense plant.
• July: Harvest. Water daily in hot weather.
• August: Harvest. Take cuttings for the winter.
• September: Cut back and bring indoors before nights fall below 5 °C.
• October: Indoors in a bright spot. Water less.

Edible and useful

Leaves (June–September)

From June to September, regularly cut stems of 10 to 15 cm, just above a node: the plant grows bushier and you always have young, tender leaves. Vietnamese coriander tastes spicy and fresh, of coriander with a hint of lemon and pepper. The leaves are eaten raw: in Vietnamese salads and summer rolls, with eggs, and scattered over noodle soup at the end. In Malaysia and Singapore it goes into laksa. Cooking weakens the flavour. In winter, indoors in a bright spot, you can pick a few leaves now and then.

Storing

Fresh is best. Stand the stems in a glass of water on the worktop, like a bunch of flowers: they stay fresh for a few days. Drying is not worth it, as the leaves lose their aroma. A stem in a glass of water roots in a week or two: that gives you a new plant straight away.

Caution: Vietnamese coriander is a kitchen herb: eat it as a herb, a handful of leaves in a dish, not as a vegetable. Wash the leaves well if you eat them raw. If you are pregnant or breastfeeding, stick to normal kitchen amounts. The plant does not tolerate frost and already suffers below 5 °C: bring the pot indoors in September.

Eating and using is at your own risk: see the terms of use.

Recipes

• Vietnamese chicken and cabbage salad (gỏi gà) (Dish · 4 people · 45 min)
• Summer rolls with prawns and Vietnamese coriander (Dish · 8 rolls · 40 min)

Did you know?

• In Vietnam it is called rau răm and is widely used in salads, soups and noodle dishes, for example in a chicken salad.
• Despite its name it is not related to true coriander (the carrot family): it belongs to the knotweed family, like rhubarb and buckwheat.
• It used to be called Polygonum odoratum and is also used in Malaysia and Singapore in laksa, which is why it is also known as ‘laksa leaf’.