Gardening's new rules: How to grow plants in the climate-change era

Asia's Tech News Daily

Gardening's new rules: How to grow plants in the climate-change era

Climate change is leading to new ways of gardening that are better not only for the planet but also for us. By Maggie Barry and Jane Clifton.

Climate change can seem like one endless, dispiriting injunction to stop doing things we have always enjoyed doing – but gardening is one exception. Around the world, climate-mitigation efforts are hitting on plants as a potent part of the solution.

The definition of gardening has lately widened to include “rewilding” – letting plants grow as they wish – which may be the easiest, lowest-maintenance greenhouse-gas weapon we have.

But growing plants anywhere faces new technical challenges. New Zealand has just experienced its warmest winter since records began. Our winters are not just warmer but about a month shorter than they were 80 years ago. It’s a similar pattern in the US, where evidence gathered over more than a century shows the first frost of the year is arriving more than a month later than it did 100 years ago.

The plants we choose will have to change, because climates are changing. Even native plants may struggle to adapt.

New Zealand’s primary horticultural ideas bank is our civic botanical gardens. Well-known horticulturist Jack Hobbs, for one, is using his leadership role at the Auckland Botanic Gardens to encourage more people to garden within the new parameters that climate change has introduced.

As he puts it, he’s in “the wellness industry”. “Without plants, there is no life.”

The Auckland gardens aim not just to connect their million annual visitors with nature but also to use the “star” system staff there have devised to help gardeners adapt to a rapidly changing environment by choosing the most suitable plants for the new climate.

With staff monitoring a wide variety of plant types daily, Auckland, like public gardens worldwide, is building a useful data bank of how the climate is affecting flora.

Pragmatic US gardeners, perhaps having experienced weather extremes for longer, have already embraced “dry” gardens, with plantings chosen to thrive with less water. These include Mediterranean plants such as lavender that enjoy low rainfall and free-draining soil; “xeriscapes”, which group together plants with similar water requirements according to the various conditions within a garden site; cacti and succulents; and prairie plantings dominated by grasses and perennial and annual plants.

Britain’s Royal Horticultural Society is warning that much of the country could eventually become frost-free, meaning the tree someone plants today may not survive the climate in 30 years’ time. The society is calling for the nation’s estimated 27 million gardeners to join “the greening of Great Britain”. People are being encouraged to grow more plants and replace fences with hedges.

Flora’s headline benefit is carbon sequestration, converting greenhouse gas to oxygen. It also fosters biodiversity by providing habitat and food for insects, animals and birds. Areas of dense planting can reduce air pollution by absorbing particulates, and can dampen urban and traffic noise.

Hobbs’ top checklist item for gardeners is mulching. New Zealand’s councils warn of growing water shortages, with increased use of metering and charging. Some have subsidised water butts or tanks to encourage residents to collect roof water for irrigation.

Covering the soil with rotted or chipped organic matter keeps weeds down and conserves water. Different grades of bark, wood chip, pea straw or even grass clippings can do the job inexpensively. It needs to be laid over – rather than dug into – well-watered soil, and ideally topped up through the year.

Over time, mulch will also keep the soil healthier by fostering billions of microorganisms. The gardener’s extra pay-off is healthier plants, as damaging rust and bacterial diseases are kept at bay and can’t disrupt beneficial insects.

An early adopter of the green gardening movement, Hobbs was for a time considered a dangerous iconoclast in the 1990s for his attitude to disease and insect sprays. Studying horticulture in Europe in 1990 hardened his resolve on cleaner practices.

“Denmark was way ahead of us, stopping the use of certain chemicals and prohibiting wastewater being allowed to flow into groundwater, instead requiring it to be held and recycled. It made a lot of sense and ultimately led us to build a series of raingardens, swales and wetlands using reeds and other plants to filter heavy metals out of the run-off from the carparks and paths.”

Serious rift

Hobbs’ water innovations were uncontroversial, but his captain’s call to stop spraying the garden’s roses caused a serious rift. Legendary rose breeder Sam McGredy was so displeased that he relocated his highly successful annual Rose of the Year show from the Auckland gardens to Hamilton. Like many growers at the time, he was worried the plants would get sick, or at least become unsightly with black spot, rust and other disfigurements.

This was, after all, the largest rose-display garden in the country. Not spraying in humid Auckland was regarded as a particularly brazen act of anarchy.

Hobbs says that some years later, although their friendship was never the same, McGredy was among many former doubters who conceded that despite a few casualties, New Zealand’s best-performing roses could thrive without spray.

“I admit it was a bit nerve-racking to see how the roses would cope, because flowers do have to look good in a public garden. In all honesty, the roses, having not been sprayed in 20 years, are healthier now and look better than they did back then. It was a relief to have your instincts backed up by good results.

Gardening's new rules: How to grow plants in the climate-change era

The pollinator-attracting lavender flower. Photo / 123RF

‘The problem with spraying is it not only kills off diseases and pests, but also all the beneficial insects, too, which leaves a vacuum for those vigorous bad pests to reinfest.”

Hobbs also wanted to spare staff the health risk of chemical exposure. “Staff were in the gardens dressed like spacemen, with four or five different chemicals in a cocktail of spray. Sure, they excluded the public while they were spraying, but the drift was going everywhere. Then, an hour later, people were sticking their noses into a rose that probably would have glowed in the dark.”

The Auckland facility has a free online database of hundreds of plants it has
trialled and that currently perform well in the region’s conditions. Aspiring growers can research cultivars for scent, wildlife benefits, dry tolerance and other attributes.

It has recently attained carbon zero status and received the 2021 Healthy Parks award for innovation, community engagement, excellence and sustainability.

Restoring hedgerows

Global research suggests even a small individual planting effort per household can have a useful carbon-reduction effect. The United States’ National Wildlife Federation estimates that if that country’s 91 million gardening households planted just one shade tree in their yards, those trees would absorb about 2.25 million tonnes of carbon dioxide each year.

And if the UK’s unkempt hedgerows are restored to pre-war dimensions, as is now being attempted, they would sequester enough carbon to accelerate the country’s emissions reduction, according to research by the Campaign to Protect Rural England.

Environment Secretary George Eustice has just welcomed the campaign’s target of increasing hedgerows by 40 per cent as an important component of reaching net zero by 2050. The British Government is committed to paying £15 billion between now and 2050 to farmers and landowners who plant woodlands.

Ireland is researching the exact carbon sequestration of its hedgerows.

New Zealand has no direct hedgerow equivalent, but a number of recent Government policy proposals are aimed at protecting wilderness areas and encouraging the covenanting of more. However, it is not proving a simple policy-design exercise. The proposed Significant Natural Areas rules would forbid landowners from using or changing tracts of land. Having caused a national uproar, they are now being reworked.

New housing policy is driving more greenfield development, creating inevitable tension with the pending schedule of protection for significant and valuable soils, such as that suitable for horticulture. Infill housing is displacing urban backyard flora, and councils are typically against residents even cultivating their berms.

Economic potential

Conservationists are increasingly challenging local and central government’s habit of spraying weeds, especially along motorway edges and similar wasteland areas.

A chief objection is the use of glyphosate – the agent in weedkillers such as Roundup – which many other countries have restricted or banned after some evidence of carcinogenic risk. Others question the lost value of allowing plants to grow naturally on these areas, provided traffic visibility and safety aren’t impeded.

Records released in September under the Official Information Act show highway contractors sprayed about 30,000 litres of glyphosate in each of the previous three years – a defoliation project spanning the length and breadth of the country.

Gardening's new rules: How to grow plants in the climate-change era

The honey-loving tūī. Photo / 123RF

Conservationists say wilderness corridors merit extra consideration in high-monoculture forestry areas, especially given the boost here in carbon-farming afforestation of recent years.

The UK is even considering the economic potential of rewilding. The Campaign to Protect Rural England says for every £1 invested in hedgerows, up to £3.92 could be generated in the wider economy, with hedgerow restoration creating 25,000 jobs.

However, it’s not feasible to let all weeds rip, given that so many introduced plants are bad for habitats, displacing desirable flora. Weedkiller has proven an indispensable weapon against some of the most destructive.

The Department of Conservation has a bounty on “the dirty dozen”, which includes the most invasive species such as old man’s beard (Clematis vitalba), common buddleia, tradescantia (wandering willie) and English ivy. But it counts 3000 imported plants as unwanted.

Some can be knocked back by importing other species to help eliminate them. Introduction of the ragwort flea beetle has helped reduce ragwort, and the buddleia leaf weevil has been skeletonising the pest plants and the harmless hybrid cultivars alike for several years.

Home horticulture boom

In this country, the biggest spur to home horticulture for many years has been the serendipitous effect of Covid-19 lockdowns. Unable to spend money on overseas travel, and with labour and material shortages impeding home-improvement splurges, New Zealanders have increasingly turned to gardening. Both retail and specialist nurseries report rapidly sold-out stock. To get particularly sought-after plants, buyers routinely have to go on a waiting list until the next cultivation season.

Some stockists have even rationed vegetable-seedling sales, thanks to a steep rise in people growing their own food in ground-level and raised beds and covered “pods”. Space and location seem no impediment, with a welcome new craze for balcony and windowsill gardening.

Much of what’s “new” in climate-change gardening is really old wisdom adapted for new circumstances. From the 1960s, UK plantswoman and designer Beth Chatto, for instance, did pioneering work in dry gardening, little imagining how the call for it would expand with global warming.

Newer fields of research give gardeners even more potential benefits. For instance, in addition to being drought-hardy, plants with rough, hairy and small oval-shaped leaves have been determined as the most effective at capturing minute particles and improving air quality. Common garden varieties such as furry greyish lamb’s-ear (Stachys byzantina) and yew trees (Taxus baccata) get two green ticks as well as being aesthetically pleasing.

The new gardening movement will continue to throw up its heretics. British botanist James Wong, a leading light of the current indoor-plant craze, recently told his followers he doubted the old received wisdom that indoor plants purified the air was true.

It’s a fact that plants convert carbon dioxide to oxygen, a feature that’s sold millions of peace lilies, mother-in-law’s tongues and spider plants. But, Wong says, although a Nasa study five years ago found plants do remove toxic compounds in sealed chambers, it’s an effect unlikely to be replicated at home to the same extent.

Given the air movement through most rooms, a subsequent study found it would take up to 1000 plants per square metre, depending on the variety, to achieve an effect. Many new gardeners would be up for that challenge, but fortunately the benefits to the planet from gardening extend beyond closed doors.

Internet Explorer Channel Network
Asia's Tech News Daily
News Related

OTHER NEWS

'Good prospect' Tiwai smelter will delay closure if aluminium prices stay high - govt officials

By Phil Pennington of RNZ Government officials are confident the Tiwai Point aluminium smelter will not close if aluminium prices remain high. But they warn there are risks this will ... Read more »

Crashes, drunken assaults: Police kept busy in Auckland overnight

It’s been another night of bad behaviour in Auckland with police responding to a steady stream of crashes and disorderly conduct, much of it fuelled by alcohol. A police spokeswoman ... Read more »

Locals flee massive eruption at Mount Semeru, Indonesia

Locals flee massive eruption at Mount Semeru, Indonesia. Source / @TheInsiderPaper via Twitter Read more »

Emma Watson to re-enter spotlight in Harry Potter reunion after lengthy break

Harry Potter actress Emma Watson has recently re-emerged on Instagram after “going underground”, and is finally set to grace screens again following a long and mysterious break from the spotlight. ... Read more »

Indonesia volcano eruption: One dead and dozens burned on Java island

The highest volcano on Indonesia’s most densely populated island of Java spewed thick columns of ash, searing gas and lava down its slopes in a sudden eruption triggered by heavy ... Read more »

World reacts to Ajaz Patel's 10-wicket haul: 'Better than Brendon McCullum's 300'

New Zealand’s Mumbai-born spinner Ajaz Patel claimed all 10 Indian wickets in the second Test, becoming only the third bowler in cricket history to achieve the feat. Ajaz, a left-arm ... Read more »

Bay of Plenty Times Christmas Appeal: How to have Christmas without breaking the bank

When you think of Christmas, things like a big ham, hundreds of lights, flowing drinks, desserts galore and a Christmas tree surrounded by presents come to mind for some. But ... Read more »

Pair rescued after falling 15 metres down Wellington track

Two people have been rescued after falling down a walking track in Wellington. It happened just after midnight on Cameron Street in Kaiwharawhara. Fire and Emergency shift manager Jill Webley ... Read more »

South African Government medical adviser reveals how Omicron is hitting under-5s

The South African Government says the Omicron variant of Covid-19 is disproportionately affecting children under five as experts rubbish the notion that the latest strain is “mild”. Government adviser Waasila ... Read more »

Covid-19 delta outbreak: Expert implores Aucklanders to 'staycation' to avoid potential spike in infections

The combination of the Covid-19 protection system and the removal of internal borders later this month could cause a massive spike in infections, says microbiologist Siouxsie Wiles. On Friday, there ... Read more »

Michigan shooting: Suspect's parents plead not guilty to involuntary manslaughter

A US judge imposed a combined US$1 million bond Saturday (local time) for the parents of the Michigan teen charged with killing four students at Oxford High School, hours after ... Read more »

China ridicules US democracy as 'disaster for voters' ahead of international summit

China’s Communist Party has taken American democracy to task, sharply criticising a global democracy summit being hosted by US President Joe Biden next week and extolling the virtues of its ... Read more »

Helicopters will be used for pole-top photography survey of power network in Coromandel and South Waikato

Powerco is using low-flying helicopters to inspect parts of its rural electricity network in Coromandel and South Waikato in December and January. The work is part of a pole-top photography ... Read more »

Cricket: 'I've got a lot of messages to get through': Ajaz Patel reflects on cricketing immortality

When he departed Wankhede Stadium after day one of the second test against India, Ajaz Patel gazed up at the honours board. The Black Caps spinner had taken four wickets, ... Read more »

Two people dead after crash in South Auckland, one person dies after falling off a ute in Manawatu

Two people are dead after a serious crash in the South Auckland suburb of Favona last night. The crash, between a car and a truck on Savill Drive, was reported ... Read more »

Coatesville deaths: Mother breaks silence on father and son who died together in Auckland

Rikki Edwards, frozen by anxiety, decided to cut off contact with her son Phoenix and his father Lee in March this year. It wasn’t meant to be a permanent break. ... Read more »

What Exactly Are Soap Brows, and Why Are They Trending?

What if we told you that the secret to thicker-looking, feathery brows lies in a simple bathroom staple that you already have? Any guesses as to what it is? Drumroll, ... Read more »

Jonny Wilkinson: Covid-19 deepening pre-existing inequalities for disabled people

It was the International Day of Persons with Disabilities yesterday. The third of December. It’s the same day every year. For well over a decade, on the same day every ... Read more »

Heather du Plessis-Allan: Tough start for Luxon

OPINION: As far as first weeks in the job go, Chris Luxon’s actually had a tough start. He’s getting no honeymoon period. Some in the media have grilled him like ... Read more »

Spy: All Blacks hope to score big with Grins, their new RTD brand

All Blacks Damian McKenzie, Anton Lienert-Brown and former All Black Stephen Donald have taken on the RTD market with the launch of Grins. The first two flavours in the low-calorie, ... Read more »

Best Buy is having a major sale on the best gifts for 2021

Looking for more gift guides and holiday tips? Sign up for Yahoo Lifestyle Canada’s newsletter! Shop these gifts at great prices with Best Buy‘s latest sale. Yahoo Lifestyle Canada is ... Read more »

Nadia Bokody: The innocent mistake that ruins great sex

A warm, foreign feeling blooms beneath my skin. I’m giddy with the sense of abandon that’s been awakened inside me. The outline of my girlfriend’s body shifts into focus as ... Read more »

Coast radio host Sam Wallace on his party of five: 'It's going to be a magical Christmas'

Ask Sam Wallace what he wants for Christmas and for once, the talkative radio DJ is at a loss for words. “No idea,” he says after a moment of contemplation. ... Read more »

Highlanders party: All Blacks KO-ed, England star punched, furniture torched, police called

Members of the Highlanders Super Rugby squad have been sanctioned over the past two seasons for off-field antics gone awry. But they pale into comparison to what happened when English ... Read more »

Spy: Famous faces and designers combine for charity at Christmas

Breast Cancer Cure launched the perfect Christmas present in its “Tees for a Cure” campaign this week with some famous faces fronting the fashion designer-led campaign. Designers of the $59 ... Read more »

Spy: Thomasin McKenzie's new starring roles

As Thomasin McKenzie hits New Zealand screens with two films this month, her schedule hasn’t slowed down. McKenzie, who is currently in New York, is in Last Night in Soho ... Read more »

Spy: A taste of NZ at Sex and the City premiere

The long-awaited Sex and the City revival series comes to screens this month — and Spy can reveal the stars will be toasting with NZ wine at the premiere in ... Read more »

England rugby star: How I changed Dunedin 'sex-wise'

England rugby star James Haskell received numerous emotional farewells when he departed Dunedin after a one-season stint with the Highlanders. And the 77-test veteran has revealed the gratitude came not ... Read more »

Auckland in line for more hot and sticky weather, temperatures "falling off a cliff" in South Island

Aucklanders are being advised to hit the cold button on heat pumps as stifling hot and humid weather continues over the next couple of days. MetService forecaster Gerard Bellam said ... Read more »

Nicola Willis at home: Who is National's new deputy leader away from the spotlight?

At home in the Wellington suburb of Karori, Nicola Willis is fresh from a significant milestone in the 40-year-old’s life. After only three years as an MP, she has ascended ... Read more »

Herald morning quiz: December 5

Test your brains with the Herald’s morning quiz. Be sure to check back on nzherald.co.nz for the afternoon quiz. Read more »

Etsy Just Revealed Its Home Decor Trends For 2022

With winter setting in and another lockdown possibly coming our way, we’re getting into all things cosy and home-y. By now, we know that interior design can boost your mental ... Read more »

These extended Cyber Week sales are still available to shop in Canada

Looking for more Cyber Monday deals, gift guides and holiday tips? Sign up for Yahoo Lifestyle Canada’s newsletter! Cyber Week sales are still available from these select retailers. Yahoo Lifestyle ... Read more »

Cricket: Black Caps embarrassed in record collapse after Ajaz Patel takes 10 wickets against India

From a hero to a bunch of zeroes. The Black Caps completely wasted Ajaz Patel’s historic 10-wicket performance in Mumbai, immediately slumping to their sixth-lowest test total – and the ... Read more »

Basketball: New Zealand Breakers suffer 24-point loss in Australian NBL season opener against South East Melbourne Phoenix

Things can only get better for the New Zealand Breakers. After their highly disrupted build-up to their season opener against the South East Melbourne Phoenix, their troubles extended onto the ... Read more »

Cricket: Black Caps embarrased in record collapse after Ajaz Patel takes 10 wickets against India

From a hero to a bunch of zeroes. The Black Caps completely wasted Ajaz Patel’s historic 10-wicket performance in Mumbai, immediately slumping to their sixth-lowest test total – and the ... Read more »

Kirstie Allsopp: 'Covid has definitely revealed a mealy-mouthed gutlessness in people'

Best known for her cosy property shows, Allsopp has become one of Britain’s most outspoken celebrities during the pandemic – Rebecca Miller/ Contour by Getty Images I am on the ... Read more »

Joshua Bassett Opens Up About Being Sexually Abused as a Child: "I Buried It So Far"

NEW YORK, NY – AUGUST 20: Joshua Bassett attends the 2018 MTV Video Music Awards at Radio City Music Hall on August 20, 2018 in New York City. (Photo by ... Read more »

Aziz Ansari engaged to girlfriend Serena Skov Campbell - report

Aziz Ansari is reportedly engaged to his girlfriend Serena Skov Campbell. The Master of None star reportedly announced his engagement news during a surprise stand-up set at the Comedy Cellar ... Read more »

Serious crash in South Auckland, person dies after falling off a ute in Manawatu

Emergency services are responding to a serious crash in the South Auckland suburb of Favona tonight. The crash, between a car and a truck on Savill Drive was reported to ... Read more »
On free-english-test.com you will find lots of free English exam practice materials to help you improve your English skills: grammar, listening, reading, writing, ielts, toeic