Weed of the week - Wild Ginger Hedychium gardnerianum
This is one of the coolest plants I have ever met. Thankfully I have never had a huge problem to manage, but when I first moved to Titirangi, I was mesmerised by the flowers, and not knowing what they were, I brought one home to put in my biggest vase.
[photo of flower coming soon]
Why I'm choosing this plant this week?
I've been testing out some tubers from the local hall in a dedicated worm farm. I'm determined to prove to the local council that we can manage all invasive plants without ever needing to use toxic weedkillers. So far they are not showing any interest, but that's no reason to give up my own trials.
Progress was slow with turning the ginger to soil. I learned that fermenting it in water doesn't work. Not even remotely. One year in and the tubers were still firm, and even sending shoots up. I decided to keep them dry, and surround them with worm farm worms. Even then, it was several months with little progress, and the shoots were trying to grow out of the worm farm. I started trimming off the edges of some tubers, and even smashing some up with a hammer, just to make it easier for the worms to get inside.
I only needed to find a few mushy tubers with nothing left but the papery skins to know that the worms were getting to work.
Success!
The surprising thing for me is the quality of the worm castings. It almost feels the way ginger tastes - refreshing, cooling, with a bit of a zing to it, and it smells amazing.
I can't help but feel that this could be the most marvellous addition to potting mix for a specific type of plant - but I don't know which.
Citizen science invitation
Want to make a dedicated worm farm and process some wild ginger?
Almost everyone knows someone trying to manage this invasive plant. If you can get just a bucket load of tubers, put them into a bucket/box/bin with a good number of worms (I used about 2 litres of worm farm worms with 20 litres of ginger), and let them get to work. I find I have to snap off any new shoots that form every month or so, and mix the contents up a little. I just used the tubers, as I'm never sure which weed seeds are still viable after several months in a worm farm, so I didn't want to risk adding the flowers and seeds. Also, I find that the green stalks are turn to soil just fine in my normal green waste compost.
I'll be testing my worm castings with some summery crops like basil, coriander, beans and sunflowers.
Stay tuned to see how I get on, and if you have any tips or observations to share then please reach out at katrina@blueborage.co.nz
Happy composting!
Katrina
PS: Want to explore ways to create a closed loop, circular system in your garden with a holistic weed management strategy? You can get started for free here, and then I have a fun online course here. My goal: to save you hundreds of dollars a year by never buying soil again, cancelling your garden waste collection, and not using any toxic weedkillers on your property. Circular gardening will save you money and make you top notch soil, using biodynamic methods.
Notes from other sources:
https://en.m.wikipedia.org/wiki/Hedychium_gardnerianum
seeds remain viable for 2–4 years
Medicinal research indicates that the plant compound, villosin, in Hedychium gardnerianum has potent cytotoxicity activity against human small cell lung cancer cells.[9]
Quentin Paynter (2017)
Summary for Landcare Research
https://www.envirolink.govt.nz/assets/Envirolink/Reports/1726-NLRC196-Impacts-caused-by-Hedychium-gardnerianum-infestations-v2.pdf
Control would cost $100 million.
Recommendation to not spray near waterways.
https://www.mdpi.com/1420-3049/17/3/3082
A study on the essential oil from leaves, contains substances that may help with Alzheimers & other neurological disorders.
Lots in Google Scholar on treating it with substances to use as animal feed for ruminants, to lower methane emissions.
Amazing historic analysis
Some cool black and white photos
https://link.springer.com/article/10.1186/s40529-021-00318-5