Welcome to Queensland's gateway to gardening - a collection of news, information, resources and ideas of interest to gardeners, especially residents of Queensland, Australia.
Get Results Gardening 12/07/19
TOP PLANT: Silver Trumpet Tree Tabebuia aurea
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GROW GROW GROW: A Dose of Nature
Get Results Gardening is a weekly mini-magazine delivered via email. It offers high-quality gardening information for SE Qld while keeping the inexperienced and even the reluctant gardener in mind. Easy plants, timely tips, ideas, motivation. Get a 3 month free trial subscription. To receive the above edition in your inbox, email before 10am Friday 12/07/19.
Garden Events 2019
Organising a garden show, open garden or similar event in Qld in 2019 or 2020? Be sure to submit some information now for inclusion in the Queensland Gardening Events Diary. Basic listings are free and featured listings are now available for a modest fee. Go to the page for more information.
From Drought to Dengue
Tank with damage to the sieve. Image: CSIRO
The return of rainwater tanks to South East Queensland may also see the return of dengue fever, suggests a recently published study.
Temperatures in tanks and buckets were monitored at several sites across Brisbane through the 2014 winter. Then Aedes aegypti - a mosquito species responsible for transmitting dengue, Zika and other diseases - was cultured under similar conditions.
It was found that the insect was capable of completing its lifecycle through a Brisbane winter. Brisbane was previously considered too cool and dry to support Aedes aegypti year-round.
Disconnected outflow. Image: CSIRO
The revival in home water collection and storage means standing water persisting for at least 32 days is now common throughout the suburbs. The research showed that tanks or buckets could potentially breed the mosquitoes, tanks having advantages in terms of higher humidity and moderated temperatures in the air cavity.
Screening of tanks will be important to preventing future dengue outbreaks, but the researchers observed native mosquito species Aedes notoscriptus in "sealed" tanks throughout the winter. They suggest that water trapped in gutters and pipes (including first flush devices) could be the source.
Aided by rotting leaves, these reservoirs become infested with eggs and larvae that are washed into tanks with the next rainfall. Adults that develop are able to escape from even tiny gaps in screens or seals.
Aedes aegypti was common in Brisbane in the early decades of the twentieth century, probably due to the number of unsealed rainwater tanks and other storages. As these were phased out, the species largely disappeared from the region. Without rigorous maintenance of the twenty-first century's water harvesting systems, the mosquito and its diseases could again pose a significant threat.
The Garden Scene
More news about plants and gardens in Queensland, plus other useful and interesting horticultural news from around the world.
Find information about growing these plants and learn about some new Australian varieties at this new website: Best Agapanthus
New City Hall a Breath of Fresh Air
Sunshine Coast Regional Council has revealed designs for its proposed new City Hall. The landscaping will be an important part of the overall concept, incorporating balconies and rootop. Plant-covered arbours will shade outdoor dining areas in the precinct. All is designed to reflect region's native plants and terrain. Construction is expected to begin in 2020. Source: Local environment the inspiration for proposed City Hall design Sunshine Coast Regional Council (June, 2019)
Sunshine Coast Verge Gardens
The Sunshine Coast Regional Council have made it easier for residents to establish verge gardens with an amendment to the local law. Provided gardens conform to self-assessable criteria, planting can occur without having to submit an application or get public liability insurance. The criteria include rules about plant heights, setbacks and access requirements. Any plants installed must be on the associated road verge planting list. Note that gardens containing plants not on the approved list or that fall outside the self-assessable criteria in any other way will still need a permit. For more information, go to sunshinecoast.qld.gov.au/Environment/Trees-Plants-and-Gardens/Plant-a-verge-garden at the Sunshine Coast Regional Council website. (May, 2019)
A new analysis of US data has shown that even quite short periods of moderate physical activity - which includes gardening - could improve health. Just 10-59 minutes per week was associated with a 18% lower risk of death from any cause, compared to people who were inactive. More time or more vigorous activity had even better effects. Source: Even low levels of leisure time physical activity lowers risk of death In another study published in the same month, a 14% reduction in risk of death was observed among low-activity participants who replaced 30 minutes of sitting time per day with light physical activity.Source: Replacing Sitting Time with Physical Activity Associated with Lower Risk of Death Mar 25, 2019 (March, 2019)
North Stradbroke Island Preserves Rainfall Record
Paper-bark tea tree leaves preserved in Swallow Lagoon on North Stradbroke Island have been used to investigate south-east Queensland's weather over the last 7000 years. Using variation in carbon isotope composition, moisture stress experienced by then-growing leaves can be determined. The period 5000 to 6000 years ago was found to be wet, but more variable and increasingly dry about 3000 years ago. Severe droughts during this phase suggests that the probability of something worse than the 1997-2009 Millennium Drought occurring in the future may be higher than the one in 10,000 years currently predicted. It also appears that Queensland was colonised at the end of an unusually wet period, The Little Ice Age (about 1450 to 1850). Source: Preserved leaves reveal 7000 years of rainfall and drought (February, 2019)
Platypuses in the Albert
Following a reported sighting in 2017, environmental DNA (eDNA) samples were taken from Logan City's Albert River during last year's breeding season. This has established the presence of animals in two sites at Wolffdene and one at Cedar Creek. Small amounts of platypus DNA were found at four other sites. The exact locations will remain secret. Source: Science confirms platypus living in Logan’s Albert River(March 2019)
As a part of their "Our Natural City" strategy, Gold Coast City Council has recently launched an initiative to help native bees. It's proposed that owners of properties over 1200m2 could be subsidised to purchase native bee hives. There may also be an opportunity to work with local bee experts, although hives only need maintenance every 12-18 months or so. Stingless bee keeping workshops offered as part of the City's NaturallyGC program are another way for residents to learn about native bees. Source: Native bees have Gold Coast Mayor buzzing (March 2019)
Brisbane Community Composting Expands
Brisbane's 20th community composting hub has recently opened in association with the Graceville Community Garden. Instead of sending kitchen scraps and green waste to landfill, participating residents can take it to a composting hub to be turned into something useful. Source: Sustainability growing through community composting (February, 2019)
Work at Eumundi Conservation Park has recently improved a poorly drained section to allow its whole network of trails to be enjoyed in all weather. Source: Source: Eumundi Conservation Park trail network complete (March, 2019). In Brisbane, the Summit Track in the Mt Coot-tha precinct is about to get an upgrade, too. Erosion cause by high foot traffic and water runoff will be addressed with resurfacing plus new handrails. A new trail from the Brisbane Botanic Gardens to the Mt Coot-tha Summit is expected to open later this year. Source: Mt Coot-tha precinct upgrade delivers better trails (February, 2019)
Cities Scale Up Pest Attack
Recent research recording the incidence in several American cities of a debilitating scale on a species of maple tree predicted larger insect populations in the warmer south than the cooler north. Instead, they found the amount of impervious concrete and asphalt in the vicinity of the tree was more strongly correlated with infestation levels than temperature. Source: Dying Trees in Cities? Blame It on the Concrete (March, 2019)
Gympie's Strategy for Pandandus Dieback
Gympie Regional Council have just announced their Leaf Hopper Integrated Pest Management Strategy, which will combine leaf stripping (to stop associated rot from spreading) and biocontrol with a parasitic wasp. Transplanting from areas where there is an abundance of young plants available will be done and a propagation program from collected seed is planned, too. Source: Council to protect Rainbow's Pandanus Palms, Gympie Regional Council.
A Flying Visit
If you live on the Sunshine Coast, you may get a chance to see little red flying-foxes (Pteropus scapulatus) visiting the area over the next few weeks. These nomadic bats travel to the coast from the north and west to feed from (and pollinate) eucalypts and other native trees. It's expected that drought conditions in western Queensland will bring more than usual this year. The little reds are said to be noisier than the black and grey-headed flying-foxes, but are expected to head back again by late March. Source: Little red flying foresters seeking Sunshine Coast blossoms, Sunshine Coast Regional Council (February, 2019)
New IndigiScapes nursery opens, main centre closes as upgrade continues
Opening of the new native plant nursery at Redlands IndigiScapes Centre marks completion of the first stage of a five-year upgrade of the Capalaba facility. From 28th January, the main centre building, car park and some bush trails will close for the next stage, which includes expansion of the cafe and other facilities. More information about the upgrade and facilities available while work is in progress can be found at the Redlands IndigiScapes Centre website: www.indigiscapes.com.au (January, 2019)
Gardens a Haven for Pollinators
Pollinating insects are vital to natural ecosystems, agriculture and even backyard fruit and vegetable production. Maintaining pollinator populations when they're under pressure in so many ways has been a matter much discussed in recent years. A new British study looking at city-wide urban land use has found that residential gardens and community gardens (allotments) could make a significant contribution to pollinator conservation. High income households were associated with more pollinators in their gardens than low income, reflecting a greater abundance of flowering plants on average. Meanwhile, parks and public spaces were found to be poor pollinator habitats. They usually contain few flowers, not even weeds. Source: Cities could play a key role in pollinator conservation. Full study: A systems approach reveals urban pollinator hotspots and conservation opportunities (January 2019)
Not everyone loves street trees
Between 2011 and 2014, nearly a quarter of eligible residents in Detroit (USA) submitted no-tree requests and researchers decided to find out why. Economic problems resulted in big cuts to the city's maintenance budget. The large numbers of dead and hazardous trees consequently left untended contributed to urban blight. This made residents wary of new trees and the authorities planting them. Residents feared they would be left with responsibility for caring for trees and wanted a greater say in which trees were planted. Education, choice and communication were seen as a way forward. Read more: Why People Reject City Trees, University of Vermont (January, 2019)
Vale David Austin
Many readers will know of David Austin, or have encountered his world famous roses. Mr Austin passed away on 19 December 2018, aged 92. His breeding work brought the beauty and fragrance of historic roses to new varieties better suited to the demands of modern gardeners, including repeat-flowering, disease resistance and colour range.
Hands off houseplants
Research led by La Trobe University in Australia has found that you'll help your houseplants with a "look but don't touch" approach. The slightest touch from an animal, insect or even other plants activates a huge number of defensive genes, which consumes energy. If the touch is repeated enough, growth is reduced. Source: Plants don't like touch, new study finds, La Trobe University. (December, 2018)
Unfortunately, a few plants won't make an as great a difference to indoor air quality you might hope. appreciable difference in normal home or office situations. However, scientists in America have modified a plant with a mammalian gene to extract chloroform and benzene from the atmosphere. The protein produced breaks down chloroform into carbon dioxide and chloride ions and benzene into phenol, all of which can be used within plants and actually help them grow. The subject in this experiment was pothos (Epipremnum aureum), a common houseplant. Source: Researchers develop a new houseplant that can clean your home's air, University of Washington. (December, 2018)
Future power plants actual plants
A team of scientists working in Italy have demonstrated the potential to use plants to harvest wind energy for electricity generation. The natural structure of leaves was found to convert mechanical force applied at the surface into electrical charge, which is then transferred through the plant in living tissues. By modifying a tree with artificial leaves that touch the natural leaves when blown by wind, electricity was generated. This could be harvested by what amounts to plugging into the plant. A whole tree or even a whole forest could potentially be turned into a power plant. Source: IIT researchers show how plants can generate electricity to power LED light bulbs. (December, 2018)
Dollar value of botanic gardens
Deloitte Access Economics has recently studied the Royal Botanic Gardens & Domain Trust in NSW to quantify the value its gardens return to the people of that state. The Trust oversees three gardens and a parkland in the Sydney region. These contributed about $140 million to the NSW economy in the 2016-2017 financial year. The majority of this was attributed to interstate and international tourism. The value delivered to NSW residents in terms of social/cultural benefits was estimated at $186 million per year. The three gardens directly employ the equivalent of 231 full-time employees, but the number of jobs created when suppliers and tourism were included was estimated at 1,116. That is, for every person employed full time, more than three full time jobs (or the equivalent) are indirectly created in other sectors. The full report can be downloaded from rbgsyd.nsw.gov.au/stories/2018/more-than-just-parks-and-gardens (October, 2018)
Recently released results of a psychological study suggest greener neighborhoods may improve children's brains. 11-year-olds living in urban areas of England were assessed. Even after allowing for socio-economic factors associated with neighbourhoods, more greenspace was correlated with better spatial working memory. This cognitive function records and processes information about an individual's surroundings and is related to attention control. It's also correlated with academic achievement. While this study couldn't prove that the environment directly caused the better memory performance, it points the way to further research and another possible benefit of more parks and gardens in cities. Source: Greener neighborhoods may be good for children's brains. Full report: The role of neighbourhood greenspace in children's spatial working memory (September, 2018)
Should Brisbane zip it?
Brisbane City Council has released more details of the zipline tourist attraction proposed for the Mt Coot-tha forest, which includes two ziplines and a treetop bridge walk. A short animated video showing how they will look can be viewed here. Council assures residents that environmental and cultural values of the precinct will be respected, but community opposition is developing. Besides the forest, the lookout and the botanic gardens will be affected. More information: Detailed designs for Mt Coot-tha Zipline unveiled and Mt Coot-tha zipline. (September, 2018)
Bee-eaters to bee savers
Even though it eats bees, Australian native bird species the rainbow bee-eater, could help bees in an unlikely way. The indigestable bee wings are regurgitated in a pellet. By analysing these pellets, Biosecurity Queensland hopes to detect incursions of Asian honey bee which could be carrying the dreaded varroa mite. Bee keepers and residents of the Townsville area are being asked to look out for rainbow bee-eater roosts and report them so that pellets can be collected. More information: Bird barf busts bad bees (August, 2018)
Flowers trapped in amber have shown that fragrance evolved as early as 100 million years ago - before showy petals - as a way of attracting pollinators to primitive flowers. Even though the scent compound themselves can't be analysed, but the tissues responsible can be identified. The fact that species alive today have retained similar structures suggests the fragrance chemicals produced were also similar. Source: Those fragrances you enjoy? Dinosaurs liked them first (August, 2018)
Status of a study's participants living near vacant lots in Philadelphia, USA were recorded before and after the lots received different levels of rehabilitation. Those within a quarter-mile radius of greened spaces averaged a 41.5% reduction in feelings of depression compared to those near lots that remained abandoned. A basic clean-up of trash without addition of grass and trees had no effect. Full report: Effect of Greening Vacant Land on Mental Health of Community-Dwelling Adults JAMA Network Open (July, 2018)
TV sports coverage captures environmental data
Researchers have been able to analyse plants growing around recognisable landmarks in video footage of Belgian cycle race the Tour of Flanders recorded between 1981 and 2016, scoring leaves and flowers present on specific days. This showed that prior to 1990, few trees had produced their spring foliage in time for the Tour. After that, more and more trees in leaf were visible, correlating with with average temperatures for the area rising about 1.5°C over the period. This method of observing climate and other environmental changes could utilise footage of events like marathons, golf tournaments or open-air festivals in addition to other cycle races around the world. Source: TV coverage of cycling races can help document the effects of climate change, British Ecological Society (July, 2018)
Queensland Landscape Architecture Awards
The Australian Institute of Landscape Architects has announced the winners of its 2018 Queensland awards. Awards of Excellence in various categories included Palmwoods New Town Square, Wembley Link Pathway Public Art (Logan City), Rockhampton Riverside, Centenary Lakes Nature Play, Home of the Arts (HOTA) Outdoor Stage (Gold Coast) and the Brisbane Airport Landscape Setting Strategy. Full list of awards, recipients and further details: 2018 AILA QLD Landscape Architecture Awards. (June 2018)
Bundaberg welcomes new nut
The Bulburin Nut (Macadamia jansenii) is a rare species of macadamia found only on one small area of Bulburin National Park near Gin Gin. As part of the Keeping Bulberin Nut Secure project, 40 trees are to be planted in Bundaberg Botanic Gardens. This species cannot be reproduced by seed and must be vegetatively propagated. The gardens already grows several of the original Macadamia species. Source: Source: Botanic Gardens goes nuts for macadamia conservation (June 2018)
Changing of the guard for Ipswich jacs
Four jacarandas trees on Brisbane Terrace Goodna are to be removed and another five monitored as their poor health poses a safety risk. A storm earlier in the year felled another of the trees, which prompted inspection of all 28 trees. They were was planted in 1932 (when Brisbane Terrace was the main road between Ipswich and Brisbane) and have been subjected to droughts and floods in the time since then. The four individuals removed will be replaced by new jacatandas of advanced size. Source: Jacaranda trees reach end of life(May 2018)
Tallebudgera tides via boardwalk
A new boardwalk within the Gold Coast's Schuster Park Natural Area, extending the peninsula nature trail by 120 metres. Constructed from composite fibre materials to withstand salt water, the boardwalk will enhance opportunities for nature observation with minimal disturbance to the sensitive tidal environment. The city's new Urban Habitat Creation Program was also demonstrated at the opening. Artificial hollows are created in suitable trees (dead or alive) and managed for wildlife habitat. Source: Boardwalk takes visitors into Tallebudgera's hidden gems (March 2018)
Toowoomba, Singapore exchanging excellence
Following a visit to the Toowoomba Carnival of Flowers by a party from Singapore's renowned Gardens by the Bay, an agreement has been signed for a staff exchange and training program involving Toowoomba Regional Council and TAFE Queensland South West. In addition to the opportunity to share knowledge and expertise, the Council see potential to promote the region in Singapore. Source: Gardens by the Bay, Singapore MOU highlights bold ambitions (March 2018)
Wallabies rock in Ipswich
The brush-tailed rock wallaby is the City of Ipswich's faunal emblem but has been listed vulnerable to extinction. To aid the species' survival, a plan has been developed by Ipswich City Council including reducing pest plants and predators while improving connectivity between habitats. Some 2200ha of prime habitat at Flinders-Goolman Conservation Estate has already been purchased. Source: Recovery Plan for iconic brush-tailed rock wallaby (March, 2018)
Avoid Urban Tree Thirst
Researchers in North Carolina USA looked at Quercus phellos to both in the landscape and in laboratory conditions study how urban trees could be affected by water stress. Higher temperatures could increase tree growth - provided the trees had adequate water. Also, scale insects had little effect. On the other hand, if trees were water stressed, growth rate was lowered, even more so if combined with heat and/or scale insects. Source: Lack of Water is Key Stressor for Urban Trees (March, 2018)
Some older news items of continuing interest have been moved to appropriate subject pages. Check the Guide to Pages or use the search function at the top of the page.