Why every garden needs the most important herb in rongoā

You can use this native medicinal plant to make a salve, throat gargle, and a natural perfume.

Kawakawa are small trees or shrubs with heart-shaped, dark green leaves. They're often full of holes made by very hungry kawakawa looper moth caterpillars (Cleora scriptaria).

Piper excelsum can grow to 4m tall, although they're often much smaller, with jointed brownish branches.

They grow widely throughout Aotearoa around parks and bush margins, in gardens, and like to be close to the coast.

Trees are either male or female. Males produce long, thin flowering spikes that start green and darken with age. Female trees produce shorter, plumper green spikes that ripen to orange fruit called tākawa. People quite often mistake the male spikes for the fruit, but the differences are clear if you observe the plant over time (see page 38).

The similar-looking Three Kings kawakawa (Piper melchior) is endemic to Manawatāwhi/Three Kings Islands, but it's also grown on the mainland as an ornamental. It has larger leaves and larger, blander-tasting fruits.

Māori healers believe that leaves with looper moth holes are the most effective in rongoā rākau (traditional Māori plant remedies). Recent research indicates that when a caterpillar munches on a leaf, it triggers the plant to produce higher concentrations of its natural defensive compounds.