How To Grow Australian Native Oregano

Australian native oregano with a mass of purple flowers

A highly ornamental shrub with wonderfully aromatic mint-scented leaves and a gorgeous display of lilac, pink or white flowers in spring. The leaves are edible and can be used to flavour a variety of dishes, imparting a strong mint flavour with a slightly citrus tang. It’s versatile in the garden too, as a feature plant or trimmed into a hedge.

What you need to know about native oregano

Name: native oregano, round-leaf mint bush (Prostanthera rotundifolia).

Height: up to 2m.

Plant type: perennial shrub.

Climate: cool and warm temperate, sub-tropical.

Soil: moist and well drained, enriched with organic matter.

Position: full sun to part shade, with protection from strong winds.

Foliage: small, round and strongly aromatic.

Flowering and fruiting: a profusion of lilac, cup-shaped blooms appear in spring. Pink and white flowering varieties are also available.

Feeding: feed after flowering with a complete organic-based fertiliser.

Watering: water regularly.

Appearance and characteristics of native oregano

Native oregano is an attractive perennial shrub with small, round green leaves and a profusion of lilac, pink or white blooms in spring. The cup-shaped blooms are so prolific they almost cover the foliage. It grows quickly, eventually reaching up to 2m tall and wide. The leaves are strongly scented with an earthy mint and slight citrus tang – ideal for cooking or including in a sensory garden.

Once established, it is moderately frost and drought-tolerant. However, native oregano will fare better when watered regularly, especially during hot, dry periods. It’s a great "indicator" plant – it begins to wilt when conditions are little too dry, but give it a good, deep watering and it will quickly bounce back.

Purple flowers of a native oregano plant

Uses for Australian native oregano

Plant native oregano in the herb patch, giving it ample room to grow. Alternatively, it responds well to pruning, so can be trimmed into a hedge and used as a border for the herb patch or garden beds. It also lends itself beautifully to topiary, where it can be clipped into balls or other geometric shapes. Harvest the leaves as needed and use them to flavour meats and sauces, or brew some to make a tea.

How to grow native oregano

Choose a spot in full sun to part shade with well-drained soil. In areas with scorching-hot summers, it’s best to plant it in part shade to provide protection from the harsh sun. Enrich the soil with compost and pelletised organic fertiliser and fork in well. Dig a hole twice as wide and to the same depth as the existing root ball. Remove the plant from its pot, loosen the mix to free the roots and place in the centre of the hole. Backfill with soil, firm down and water well.

Mulch around the base of the plant with an organic mulch to help retain soil moisture and suppress weed growth.

Caring for native oregano

Native oregano grows quickly into a medium-sized shrub. To help it remain healthy and bushy, remove one-third of its growth annually after flowering. Plants in pots can also be lightly trimmed after flowering to help maintain shape and size.

Native oregano is rarely bothered by pests or diseases.

How often should you water and feed native oregano?

Water regularly until established, then occasionally throughout the year. Increase frequency during periods of hot, dry weather. Mulching will also assist with retaining soil moisture.

Feed after flowering with an organic-based fertiliser suitable for native plants.

How and when to harvest native oregano

Harvest the leaves as needed throughout the year.

How to propagate native oregano

Grows best from semi-hardwood (woody but flexible) cuttings. Take cuttings 5–10cm long, remove half of the lower leaves and dip the base into a rooting hormone. Insert the cuttings into a tray filled with propagating mix and gently firm the mix around the base of the cutting to secure. Position in a warm, protected spot and mist regularly to keep the soil moist. Roots can take 3–4 weeks to form.

Safety tip

After applying fertiliser, delay harvesting for a few days and rinse well before cooking and eating. If using products to deal with pests, diseases or weeds, always read the label, follow the instructions carefully and wear suitable protective equipment. Store all garden chemicals out of the reach of children and pets.