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 08/03/19
In this edition:
TOP PLANT: Mandevilla (Dipladenia type)
WORLD OF PLANTS: Cities Scale Up Pest Attack
BASICS: Agapanthus Advice - Maintenance
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 08/03/19.
Garden Events 2019
If you're organising a garden show, open garden or similar event in Qld in 2019 and you already have a date locked in, be sure to submit some information now for inclusion in the Queensland Gardening Events Diary. Dates can be added a year ahead or even more, helping give your event plenty of exposure to potential visitors and exhibitors. Basic listings are free and featured listings are now available for a modest fee. Go to the page for more information.
Join the Wild Macadamia Hunt
Australia's most commercially successful "bushfood" so far is the macadamia. They're grown on a mass scale around the world, but those plants are the result of a century and a half of breeding and selection. Meanwhile, the progenitors of these plants and their relatives are rare and threatened in the wild.
One of the initiatives to save the survivors and the genetic diversity they contain is The Wild Macadamia Hunt. It's one you can get involved in, too.
Macadamia species are native to rainforests of SE Qld or Northern NSW and many private properties could contain remnant wild trees or their direct descendants. Extensive planting of macadamias also means that many trees are found outside of rainforest.
If you live in the macadamia's natural range and know of an old specimen (~100 years or more), you can register the tree and send in some photos. If the submission warrants further investigation, you'll be sent a special kit which will enable you to collect a leaf sample (with permission!) for genetic analysis.
Instructions and more information, including identification guides to target species, can be accessed via the website: The Wild Macadamia Hunt
You can also join the Wild Macadamia Hunters Facebook group to share the story of your tree and learn more about macadamias.
Thanks to Healthy Land & Water for contributing to this story. The Wild Macadamia Hunt is an initiative of Healthy Land & Water with support from the Brisbane City Council and the Macadamia Conservation Trust.
The Garden Scene
More news about plants and gardens in Queensland, plus other useful and interesting horticultural news from around the world.
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)
Nanango students sunflower stars
Meanwhile, Nanango State High School are the champions for the second year in a row in the University of Queensland Sunflower Competition, beating 102 other high schools across Australia. Using a specified seed variety and pot size, students are allowed to experiment with cultural factors such as growing mix, fertiliser and watering to achieve the heaviest plant possible in a 12-week period. Other awards were made in several categories including the tallest and most ornamental sunflowers. View the full results here.
Queensland pumpkin royalty deposed
Steven Fritz of Marburg has taken out the Royal Queensland Show (Ekka) Giant Pumpkin Competition with a 206kg fruit. Competition veterans Tony and Geoff Frohloff came in second and third. A 40kg entry from Bullyard State School (near Bundaberg) won the school competition.
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 extiction. 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)
Piccabeen Palms Help Transform Palmwoods
Palmwoods in the Sunshine Coast hinterland officially opened its new Piccabeen Green town square. In addition to a boardwalk, seating, shade structures, artwork and historical information, the project includes 54 Piccabeen palms (Archontophoenix cunninghamiana) which have inspired its name. Source: New $3M town square transforms heart of Palmwoods. You can get a drone's-eye view of the completed landscaping with this short video. (March 2018)
Geothermally cool koala research
Brisbane City Council has funded and started construction on a new research facility at Lone Pine Koala Sanctuary. In addition to laboratories investigatong koala disease and genetics, there'll be public viewing areas and interactive learning displays. The centre will be self-powered by solar panels and a geothermal cooling system. Source: Construction underway for Koala Research Centre (February, 2018)
Redlands koala tree vandalised
A high-value koala food and refuge tree in Wellington Point has been vandalised by cutting, drilling and the application of a chemical. One of the suburb's iconic poincianas has also been repeatedly hacked at, possibly in an attempt to speed decay of the tree. Source: Koala food tree and others icons at risk from vandalism (February, 2018)
Birds are coffee lovers, too
While coffee lovers may have a preference between arabica or robusta, what are the implications for birds in parts of the world wehere coffee is grown?
A study in India compared bird populations where coffee is grown in shade (usually arabica) with full-sun robusta. While the former supported an greater number of different species, the robusta plantations supported higher densities of certain sensitive species. This is good news as robusta becomes predominant worldwide. Robusta also requires less pesticides. Source:Birds and beans: Study shows best coffee for bird diversity (February 2018)
A Melbourne ear, nose and throat surgeon has reported an increase in ear injuries caused by yucca leaves entering the ear canal. In some cases, this resulted in permanent hearing loss. The ABC interview does not specify which type(s) of yucca are the cause. Neither does the first page of the published medical report (free to view without subscription here), but the plant illustrated appears to be Yucca elephantipes. This is certainly the most likely culprit, given how common this species has become in Australian gardens. It can grow many metres tall, so there's a chance it could reach ears at all heights. (January, 2018)
Ipswich preserves an original resident
Ipswich City Council has preserved a huge Eucalyptus tereticornis (Queensland Blue Gum or Forest Red Gum) by during an upgrade to Riverside Drive at Pine Mountain. A low pressure sucker vac was used to locate the root plate of the 35 metre high tree, allowing a concrete floodway to be modified to avoid damage. Council has undertaken to maintain the specimen, an original tree of the area which managed to escape the timber industry. Source: Health of 'pioneer' Blue Gum a priority during roadworks (December 2017)
Another award for Toowoomba carnival
The Toowoomba Carnival of Flowers in conjunction with The Chronicle Home Garden competition has won the inaugural Rural Green Space Award at the 2017 Australian Institute of Horticulture national awards, honouring the role these events play in promoting the benefits of green spaces. The carnival is also a current Tourism Australia Major Festival and Event gold winner. Source: TRC wins inaugural national horticulture, Qld Tennis awards (November 2017)
Logan gets more walkable
A shared pedestrian and cycle pathway in Logan Central, connecting Railway Parade and Logan Gardens, is officially open. It features landscaping, seating, shade structures and arbours at both ends. New pathway officially opens (November 2017)
Toowoomba's beautiful rubbish
Toowoomba are extending their beautification commitment to their waste facilities with an annual garden competition involving staff and Ability Enterprise (providing employment to the disabled and long-term unemplyed). Ravensbourne Waste Facility has taken out first prize in the 2017 competition. Source:
Ravensbourne Waste Facility takes out garden gong (October 2017)
Community gardens get thumbs up in Moreton Bay
Following a successful trial at The Hills District Community Garden in Bunya, Moreton Bay Regional Council has officially undertaken to allow more community gardens in the region. A guide and expression of interest form is available on the council's website. Source: Community gardens to blossom in Moreton Bay (October 2017)
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.