Oval Leaf Mint Bush

Oval Leaf Mint Bush (Prostanthera ovalifolia) is the native shrub that stops people mid conversation in spring, when the whole plant disappears under purple flowers. It grows to around 2.5m tall and 2m wide, fast enough to be useful as an informal screen, and the small grey green leaves release a sharp mint scent whenever you brush past. Few Australian shrubs give this much colour for this little effort.

Why you'll love it

• A solid month of purple. Through spring the foliage almost vanishes behind massed tubular flowers, which is rare in a native shrub of this size.
• Aromatic foliage. The leaves carry a clean minty oil, so brushing past a path planting releases the scent.
• Birds and pollinators both. Small honeyeaters take the flowers, and bees work them all day.
• Quick to a useful height. It reaches screening height in two to three seasons, faster than most native shrubs of the same size.
• Frost hardy and wind tolerant. Comfortable from subtropical gardens through to cool temperate districts that get regular winter frost.

Where it works best

Informal screening and hedging. Plant 1.2m apart for a soft screen that closes in two to three seasons. It clips well enough for a loose hedge, though a hard formal shape is not its strength.

Mass planting. Groups of five or more at 1.2m centres read as a purple drift in spring and a grey green mound the rest of the year.

Feature planting. A single plant beside a path or a seat puts the scent within reach and gives one strong show a year.

Growing Oval Leaf Mint Bush in Australia

Position and climate. Full sun to light shade, with best flowering in full sun. It suits subtropical, warm temperate and cool temperate gardens and handles frost once established. In hot inland gardens give it afternoon shade, because it prefers a cool root run.

Soil. Free draining soil is not negotiable. Mint bushes suffer quickly in wet ground, so raise the bed on clay, add coarse compost and mulch 75mm deep to keep roots cool.

Water and feed. Water deeply twice a week through the first summer, then weekly in dry spells; it is not a plant to leave entirely unwatered. A low phosphorus native fertiliser in early spring is plenty.

Pruning. Prune straight after flowering, taking up to a third off and always cutting into leafy growth. Skip this and the plant goes woody and open early. Even with good pruning, expect a useful life of six to ten years rather than decades.

What to expect when it arrives

We grow it in tube and in 140mm pots sold in packs of 10. Both arrive as young single stemmed plants, and the 140mm pack is the sensible buy for a screen because the price per plant drops sharply. Tube stock catches up within a season.

Plants travel upright and are delivered Australia wide, with delivery from $29.95 and a minimum order of $300 before delivery. Tip prune once on planting to force branching low down. Expect 60cm to 80cm of growth in the first full warm season and a real flowering display in the second spring. Every plant carries our 30 day healthy plant guarantee.

Plant care guides and related reading

• Compare options in screening plants 2m to 4m.
• Browse the wider range of Australian native shrubs.
• Read how to plant and maintain a hedge.
• See more bee and butterfly plants.

Common questions

How far apart should I plant it for a screen?

About 1.2m apart in a single row. That gives each plant room to fill out sideways while the canopies still knit together within two or three seasons.

Can I keep it smaller than 2.5m?

Yes. An annual prune after flowering holds it comfortably at 1.5m to 2m, and the plant stays denser for it. Always cut into leafy wood, never into bare stems.

Is the mint scent strong enough to notice?

Only when the leaves are touched or crushed, not from across the garden. Plant it where people brush past if the scent is part of the appeal.