A few weeks ago, I attended a workshop run by the Landcare Facilitator for Langwarrin Woodlands, Ella Boyen. www.langwarrinwoodlands.org. The workshop was held on Ella’s property on the Westernport Highway which is being restored to bushland. It has the ‘traditional’ lazy driveway edged with large, tough, old clumps of agapanthus. Like all of us, Ella tries to avoid herbicide use and had been experimenting with various methods of manual agapanthus control. She told participants to come armed only with a serrated steak-knife!
ELLA’S STEAK KNIFE AGAPANTHUS REMOVAL METHOD
This method is for the patient bush regenerator who understands that ALL weed removal, regardless of method, requires follow-up. By following the process Ella has developed, your aggies will be gone within the year.
Agapanthus grow like leeks, so part the stalks and slice each stalk off as close to the ground as possible. When each stalk has been cut to ground level, criss-cross the cut stems to allow rain in to rot the tubers.
You will be left with an unsightly mound of aggies bleeding white sap which is better than healthy plants seeding everywhere. After some time, many of the tubers will have browned and died, shrinking as they do so. There will be the occasional new sprout from a residual tuber which you also give the steak–knife treatment. Eventually, the aggie dies in situ without the need for mattocking, removal by machinery or use of herbicide.
To speed up the process, Ella drove over each treated clump with her ride-on mower. This is far more difficult to do on steeply sloping sites but could be done instead with a brushcutter. The continual slashing weakens the plant. The removal process took about a year and Ella was able to plant directly into the site where the aggies once grew with no soil disturbance or residual chemicals entering the soil or water table.
An additional method Ella employed was a weed burner, especially where the aggies were infested with kikuyu. She first checked the site for frogs and other native wildlife - she has only ever found one frog sheltering in aggies at her place. She then employed the steak –knife treatment, finishing around the clump with the weedburner. Again, continual mowing accelerates their demise.
I imagine that in about 5 years time, Ella will have a eucalyptus lined driveway with nary an aggie in sight. This method is gentle on the operator and gentle on the earth and steak knives are plentiful in op-shops. Give it a try.