How do you solve a problem like agapanthus?

22:38, Mar 22 2012

Agapanthus and I have history. When we bought Wild Estate, agapanthus ruled the roost.

They filled every gap, poking their dry, seedy heads out from their snail-harbouring bushes.

We looked around the section and saw all the space we could make if we could just get rid of the agapanthus.

Agapanthus is a tenacious plant.

It can grow a new plant from a sliver of its fleshy underground stem, called a rhizome, and those purple flowers it puts out turn into dozens of hardy seeds that just adore being flung around by a northerly.

When you dig it up, you find dozens and dozens of rhizomes, with thick wriggly roots coming out of them, like something from an Alien movie.


It's planted on banks and beside roads for its indestructible qualities, its ability to grow just about anywhere with little or no maintenance required.

And even Roundup won't kill it.

So how do you get rid of a plant that self seeds freely, grows from huge clumps that cling to the ground like hooks, and is resistant to poison? 

Here's the technique we perfected removing about 20 trailer loads of the stuff:

1. Get your friends together: we had help from practically everyone who visited us at our new house. They came through the door, we gave them a cuppa, then a spade.

We also had a working bee and paid everyone for their efforts with fish and chips.

It was like a barn raising, only different.

2. Get cutting: take a very sharp machete and hack off those leaves.

Wear gloves, because those leaves ooze something nasty and can give you a rash - just another reason agapanthus plants give me the willies.

You can compost these leaves.

3. Get violent: now that your agapanthus is bald, you'll be able to get underneath it and dig out the rhizome.

With a sharp spade, get underneath the rhizome and lever it out. For really big clumps, you'll need to slice it up with your spade. I've been known to climb on top of large clumps and swear loudly while doing this.

It's great therapy.

4. Get cleaning: The important bit to remove is the rhizome, don't worry too much about getting all the white wriggly roots.

It's the rhizome that will resprout and grow more agapanthuses.

I had visions of our attempts to dig up the clumps just resulting in more little plants growing everywhere, a little like Mickey Mouse in the Magician's Apprentice trying to chop up possessed brooms.

So be thorough in collecting up as many bits as you can when you're cleaning up.

5. Get covered up: When you have disposed of your agapanthus - taking them to the dump is best, you don't want rhizomes in your compost bin - you'll need to prepare the ground for its next job as lawn, vege garden or whatever. 

The best method I've found is to cover it with old carpet and let it sit for six months or so.

You still might get little sprouts of agapanthus popping up from time to time, but they'll be tiny and easy to get rid of. Dominion Post garden writer Hannah Zwartz advised me to cover the ground with cardboard and mulch over the top.

This also works well and I've done this on my vegetable beds, which were formerly piled high with agapanthus, on the right in the 'after' photo.

If this all sounds like to much swearing and blinding, you can go the chemical route, as suggested by Weedbusters.

Do you love or loathe agapanthus? Have you ever struggled to get rid of it, or do you covet its persistent properties?