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Vietnamese Coriander

Persicaria odorata

Vietnamese coriander — also known as rau răm — is a tropical, coriander-like herb with a sharper, peppery, citrus flavour that does not bolt in heat. It is essential in Vietnamese and Thai cooking. In the UK it must be grown as a tender perennial, overwintering indoors. Root supermarket stems in water, or sow indoors in March at 20°C. Grow in rich, moist compost in full sun or partial shade; it loves humidity. Harvest leaves from June to October. Bring the pot indoors before the first frost and keep on a bright windowsill at 10°C+ over winter. It spreads rapidly in warm conditions.

Plan where to grow Vietnamese Coriander using our vegetable garden planner.

SunlightFull sun
WateringHigh
Height30cm
Spacing30cm
Germination14–21 days
Sowing MethodUnder cover
Frost HardinessTender
Sowing DepthSurface sow, press in

When to Sow Vietnamese Coriander

Sow vietnamese coriander in March, April, May.

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Feb
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Jun
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Sowing months

Time to Harvest Vietnamese Coriander

Expect to harvest approximately 3 months after sowing.

Companion Plants

Expected Yield

One pot yields a generous weekly harvest from June to first frost.

Common Problems with Vietnamese Coriander

Plant collapses outdoors after a cold night

Vietnamese coriander is tender. Do not plant out until June night temperatures stay above 10°C, and bring indoors in September.

Leaves turn red and growth stalls

Red leaves signal stress from cold or drought. Keep soil consistently moist and move to a warmer position.

Becomes leggy and sparse indoors over winter

It needs bright light. A south-facing windowsill with a grow light for 6 hours daily keeps plants compact and productive.

Plan your vietnamese coriander in the allotment planner

Drag and drop plants onto your plot and get personalised sowing reminders.

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