Hunting season for Gazanias, the pretty (awful) weed
Gazanias are a weed
Gazania are a perennial, wind-dispersed daisy from southern Africa, now widespread across Victoria. Sadly many people think they are wildflowers. But they’re not. They are evil weeds that can travel and invade undisturbed bushland.
The “Advisory list of environmental weeds in Victoria” (1) places this as one of the “very high” risk weeds - highly invasive, significant impact on natural systems, extensive potential for further spread. Oh yeah, also has allelopathic properties (2), meaning the Gazania produces chemical compounds which make the soil unsuitable for other plants to grow.
But, you can still buy a packet of Gazania seed from your local Bunnings store because the environmental weed list is only advisory - you should do the right thing, but you don’t have to. To stop Gazania being sold it must be listed as a noxious weed under Victorian legislation - the Catchment and Land Protection Act. Thanks to ABC Rural for raising awareness in this article https://www.abc.net.au/news/rural/2024-07-15/bunnings-criticised-for-stocking-invasive-weed-species-vic/104084222
Image ABC News: Else Kennedy
Thankfully, most local councils now recognise Gazania as a weed, but it wasn’t always the case. I received this email:
"I used to work at a nursery in the late 90’s. It was a council nursery and I can clearly remember the 1000s of gazanias we were looking after on their way to being planted on every highway splitter in the council area. It’s a long time ago but I remember arguing with a supervisor that they were just another weed being planted and would spread everywhere. I’m sure I wasn’t the only one who thought this. I’m sorry."
This single Gazania plant is over 2 km from the nearest infestation!
Controlling Gazania weeds
In the Mallee of north-west Victoria, hunting season for Gazanias starts now (July) and extends through summer but you’re best to try to get them before September when they start really spreading seed.
Gazanias are tenacious. We have found that if you dig out a flowering plant and leave it, there is still enough energy in the root system to get the flowers to seeding stage. Those seeds can then blow about and spread more weeds.
So if we find one in the bush and we can’t take the entire plant with us, we pull each flower head off individually and remove those, as well as pull the plant out by the roots.
This is a weed that will always be trying to sneak onto our conservation property “Raakajlim”, because these are our nearby roadsides:
Grow what instead?
Native plants of course! Even better, native plants that are local to your area. For the Mallee, try these resources “Sustainable gardening in the Mildura region” and “Water-wise nature strips - Swan Hill”.
If you absolutely must grow these daisies, you could plant a sterile form of Gazanias. The "Grow me instead" website says “It is safe to grow the new sterile Gazania cultivars listed below. They have been specially bred as non-invasive and drought tolerant with improved growth habit, foliage, flower colours and size without viable seed set. Look for these new improved sterile varieties of Gazania at your local garden centre.”
Double Gold TM
Montezuma TM
Sunset Jane TM
A hot tip: if you are buying a packet of Gazania seed, that is absolutely not a sterile hybrid!
Gazania research underway!
In 2023, many people headed out to collect Gazania seed to help researcher Ali Bajwa from LaTrobe University kick off a research project. We look forward to the results!
“In this GRDC funded project, our research team aims to understand how changes in climate and soil factors are affecting the biology and ecology of weed species affecting Australian grains. … to understand more about the most difficult weeds to manage, alterations in weed’s biology and ecology due to changes in climatic and soil factors and learn about new weed infestations.”