Polygonum odoratum VIETNAMESE CORIANDER (plant)

Rau-ram, also known as Vietnamese Coriander, Vietnamese Mint and scientifically named Persicaria odorata (formerly Polygonum odoratum), is a fast-growing, perennial herbaceous aromatic plant belonging to the Polygonaceae family. This creeping exotic variety is native to Asia, specifically China, and is widely used in Thailand and Vietnam. Its flavor is unique often described as a blend of coriander, mint, and subtle spice.

Its dark green leaves are generally oval and lanceolate, measuring 5 to 10 cm in length, with a smooth, shiny texture and occasionally wavy edges. When crushed, they release a pleasant fragrance with citrus notes.

In late summer, it produces small white to pale pink flowers in clusters.

Rau-ram seeds are tiny and brown, forming after pollination and typically dispersed by wind or animals.

- Uses:

Culinary: The foliage is a staple herb in Southeast Asian cuisine. Its fresh, peppery, and slightly minty flavor makes it popular in salads, soups (like Laksa), and stir-fries.

Medicinal: In traditional medicine, it is used for its antioxidant and anti-inflammatory properties. It is sometimes employed to help with digestive or respiratory issues. Do not consume without medical advice from a healthcare professional.

Infusions: In some cultures, the leaves are steeped to make herbal teas to benefit from its health properties.

- Planting Vietnamese Coriander:

• Plant your Rau-ram plant in a 3 to 5-liter pot, ensuring the root collar is not buried.
• Water copiously at the base of the plant immediately after planting.
• Place it in a slightly shaded location.
• It can also be grown in the ground as an annual plant in cooler climates.

- Soil Type / Substrate:

Persicaria odorata requires fertile, cool, and aerated soil, whether in a pot or in the ground. Ensure the bottom of the pot is well-drained to prevent stagnant water.

- Watering / Humidity:

Rau-ram thrives in high humidity. Water regularly during the summer; the more water it receives, the faster it grows. In winter, stop watering to prevent root rot.

- Exposure / Light:

Vietnamese Mint has low light requirements. It grows very well in shady, damp spots, offering many planting possibilities. For indoor growing, use horticultural neons or LED grow lights.

- Temperature / Hardiness:

It grows best when temperatures are between 20°C and 30°C; growth slows down below this range. It is a frost-sensitive plant (not hardy) and must be brought indoors before winter.

- Multiplication / Reproduction:

It can be propagated by seeds or very easily by cuttings. Simply cut healthy stems (10 to 15 cm long) and place them in potting soil or water in a warm, bright spot until roots form.

- Diseases / Pests:

Diseases: Fungal issues like powdery mildew or downy mildew can occur, appearing as white spots or fuzzy coating on the leaves.

Pests: Aphids, thrips, and mites may infest the plant, feeding on the sap and causing leaf deformation or wilting.