🌀Māori Rongoa

Nau (NZ Watercress)

Rorippa nasturtium-aquaticum

About Nau (NZ Watercress)

Nau (NZ Watercress) (Rorippa nasturtium-aquaticum) is a herb used in the Māori Rongoa tradition to help with Nutritional Support, Digestive Issues, Anemia, and Scurvy. The aerial parts and leaves are the parts traditionally used, taken internally.

Botanical background

Watercress is an aquatic plant species with the botanical name Nasturtium officinale. This should not be confused with the profoundly different and unrelated group of plants with the common name of nasturtium, within the genus Tropaeolum.

Source: Wikipedia, via iNaturalist

Parts used

Aerial Parts · internalLeaves · internal
🍵

Tea / Infusion

1–3 cups daily
  • Steep 1–2 tsp of dried Nau (NZ Watercress) in freshly boiled water for 5–10 minutes.
  • Cover while steeping.
  • Strain and drink.
💧

Tincture

20–40 drops in water, 2–3× daily
  • Pack dried Nau (NZ Watercress) into a jar and cover with 40–60% alcohol.
  • Seal and steep for 4–6 weeks, shaking daily.
  • Strain and store in a dark dropper bottle.
💊

Powder / Capsule

500 mg – 1 g, 1–3× daily
  • Grind dried Nau (NZ Watercress) into a fine powder.
  • Fill size 00 capsules or stir into smoothies or honey.

Contraindications

  • Pregnancy & breastfeeding — insufficient safety data; consult your doctor
  • Children under 12 — therapeutic dosage not established

Warnings

⚠️ Pregnancy & Breastfeeding

Safety during pregnancy and breastfeeding has not been established for most herbal remedies. Consult your midwife or doctor before use.

⚠️ Allergic Reactions

Discontinue immediately if you experience rash, itching, swelling, or difficulty breathing.

⚠️ Not Medical Advice

This information is for educational purposes only. Always consult a qualified healthcare provider before using herbal remedies.

Drug & herb interactions

No specific drug or herb interactions are documented for Nau (NZ Watercress) in our references. This doesn’t mean none exist — always check with a pharmacist or doctor before combining any new herb with prescription medication.

Where to find in nature

Native region

New Zealand (Aotearoa)

Climate

Temperate oceanic

Habitat

Native bush (ngahere), coastal forests, and wetlands unique to New Zealand

🌿 To see Nau (NZ Watercress) growing, visit botanical gardens, university plant collections, or specialist herb nurseries near you. If foraging in the wild, always work with an expert identifier — never consume a plant you are not 100% certain of.

Where to buy

In store

  • Health food stores (Whole Foods, Natural Grocers, Holland & Barrett, GNC)
  • Naturopathic clinics and integrative medicine practices
  • Specialist herbal apothecaries and herbalist practices
  • Farmers markets with herb vendors

Online

iHerb

Wide selection of standardised extracts, capsules, and powders with lab testing

Mountain Rose Herbs

Premium bulk dried herbs — certified organic, ethically sourced

Starwest Botanicals

Large selection of certified organic bulk herbs and powders

Herb Pharm

High-quality liquid extracts and tinctures, rigorous quality standards

Amazon

Convenient — verify brand certifications and check third-party testing

Etsy

Small-batch artisan herbalists, hand-harvested and wildcrafted herbs

Quality tips

When buying Nau (NZ Watercress), look for: certified organic labelling, clearly stated country of origin, third-party lab testing for heavy metals and pesticides, and a batch expiry date. Standardised extracts offer consistent dosing; bulk dried herbs are more economical for regular use. Avoid very cheap, unlabelled products — quality varies enormously.