Plant once, keep harvesting for free with these must-grow salad greens to reduce cost of living

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A self-confessed plant nerd is questioning why millions of Australians buy expensive vegetable crops when planting perennial Asian greens as garden ground covers can create an endless supply of tasty, free food in tropical and subtropical regions.

When supermarket prices soared Koren quickly set up a new vegetable patch to grow her own, and went foraging for free edible weeds.

Impacted by floods, fuel and fertiliser costs, record grocery prices have been predicted to get even worse, with vegetable shortages including iceberg lettuce, zucchinis, broccoli, snow peas and beans.

But boutique nursery owner Kevin Redd says people who live along the coastline, in the tropics or subtropics, should never need to be reliant on commercially grown crops.

He gave three examples of delicious leafy greens with a 'wow' factor, that are commonly grown overseas but typically overlooked in Australia.

"Even if you have the tiniest little balcony with a pot on it, these plants will thrive in our climate," Dr Redd marvelled.

"A lot of people have that forgotten little corner of their garden and they've got nothing growing [there] and they're paying $10 for an iceberg lettuce."

The first of Dr Redd's planting suggestions is Gynura procumbens, often called longevity spinach or Sambung Nyawa.

The versatile edible creeping ground cover is considered an anti-inflammatory food and thrives in warm, moist conditions.

Its leaves can be used raw in salads or cooked, and new plants grow easily from cuttings.

Dr Redd, who has a PhD in molecular ecology, a research background in plant biochemistry and once ran an adventurous catering business in Tasmania, is passionate about educating Australians about alternative edible plants.

"You should just stick a few of these in those little shady corners and you get absolutely an abundance of the stuff year round," he said.

Under a patch of bamboo in his jungle-like backyard, Dr Redd revealed the second of his picks for everlasting vegetables; the betel leaf plant.

The evergreen perennial creeper's shiny heart-shaped leaves can be eaten raw in salads or cooked. The plant is a relative of pepper and kava.

Dr Redd says the betel leaf loves shade and tastes great in stir-fries and even as a wrap for mince that's cooked on the barbecue.

Noosa chef Matt Golinski regularly uses betel leaf as a gluten-free base for canapés.

"I love the light, peppery flavour. You can put anything on them and they look awesome," Mr Golinski said.

"I grow them myself and they grow very easily so they're free, which is a bonus."

He said betel leaf plants shouldn't be confused with the stimulant drug, betel nut, which comes from areca palms and stains mouths red.

Dr Redd's favourite of the three easy-growing greens is Okinawa spinach, a pretty creeper, also known as Hong tsoi or cholesterol spinach.

The hardy low-maintenance perennial leaf vegetable grows in full sun and partial shade, but like the other two of his recommendations, is sensitive to frost.

The leaves and young shoot tips can be lightly steamed and are often used as last-minute additions to stir-fries, stews and soups. They are best not overcooked.

"It's beautiful raw and it's got this purple underside that looks absolutely amazing," Dr Redd says.

"When you put that into a salad all your guests go, 'Wow, what is that?' — they absolutely love it."

Seeds of all three plants can be sourced online but they grow quickly from cuttings.

"A lot of them are not massively easy to get and that's how I started my collection; from hippies, markets, Asian people and collectors," Dr Redd said.

Dr Redd will be a guest speaker at the Queensland Garden Expo, which is expected to attract 40,000 visitors between July 8–10 at the Nambour showground.

Event coordinator Marion Beazley said in the last five years she had witnessed a rapid rise in interest from younger families looking to grow sustainable spray-free food.

"Survival instinct went into overdrive when we first went into lockdown and people realised they had to rely on their own resources a lot more," she said.

"There's a bigger picture of environmental awareness; people are focused on food miles and the health benefits of growing their own food."

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