Tuesday, March 16, 2010

How do you solve a problem like Kikuyu? Going solar.

Probably the first post in what's likely to be a long running series – think Rocky, but with less talent and lower budget.

Let me say upfront: Kikuyu has its uses. It's a good pasture and is quite a good lawn – the sort of lawn you can enjoy walking over barefoot. In our climate, it's set and forget. But, this grass is not a homebody. It likes the jet setting lifestyle and is keen to explore every nook and cranny of your garden, sending out rhizomes like a demented octopus. And once it finds a place it likes, such as my nice new garden bed, it moves in, suppressing all around it (well, all I've tried to grow so far).  So, my challenge is to create safe vegetable enclaves in the semi-hostile territory currently controlled by Kikuyu - all without resorting to extreme chemical measures.

Talking tactics
As far as I can determine there are three main strategies to successfully conquer this persistent little plant – digging, sheet mulching and solarising. I'm currently some way into trials of all three approaches, but unfortunately this commenced before my epiphany that record keeping is a gardener's friend – i.e. I don't have any really good before photos. But, it's still very early days, so better late than never.

Going solar
I started with solarising as I didn't have all the ingredients for sheet mulching and as a new earth gardener is seem a little beyond me. Solarising on the other hand was pretty easy to grasp – get plastic, wet grass, cover grass with plastic, wait. That I felt I could do. And it required much less digging than, well, digging.

There seems to be two trains of thought when it comes to solarising Kikuyu – clear plastic vs. black plastic. Clear plastic will apparently generate higher temperatures than black plastic, whilst black plastic claims light suppression as a key advantage. I started with black plastic as I could get it in greater widths and it was cheaper than clear plastic.

 Solarising: Phase I

I started with an area that I had decided to convert to raised beds and steps after a less agile member of the family tumbled down the grassy slope that dropped away from the house (hmmm, I seem to recall that conversion bit required quite a lot of digging). Anyway, as you can see above, the slope is well covered with black plastic and remained so for about 10 weeks over summer.  I spent my time doing summery things - frolicking in the sea, having picnics and so on.

Until the day of the great unveiling...

Well, to tell the truth I unveiled the top bed about two weeks prior to the photograph and planted out a cover crop to take advantage of some rain we'd had.  But so far there's not a hint that Kikuyu plans a comeback tour.

I'd keep score, but mother nature will always win and claiming a victory will only incite some form of retribution (toads probably).  We'll call it a compromise arrangement currently in my favour.


  1. It looks alot like what we call in the UK Couch grass - and thats a terrible grass if you get it in your garden. I hope you have succeeded in getting rid of it as once I got a load of topsoil (in a previous garden) and as you say you get what you pay for - the cheap topsoil was full of the white roots from the couch grass - I spend years trying to eradicate it...........I finally moved house lol not because of the grass but I've been so careful since.

    Welcome to Blotanical - I found you through their new blog listings and wanted to come over and introduce myself and say hello. Pop over to my blog sometime you'll be made very welcome.

  2. Oh my, this is a WEED! Thanks so much for stopping by my blog! And welcome to both blogging and blotanical too. I'm a relative gardening newcomer too, so you've got much company out there.

  3. I'll keep my fingers crossed that the solarising has worked Flo! I'll also be looking out for progress reports as I'm about to try solarising after digging out as much kikuyu, couch and blackberry as I can from one of my beds. While the couch is the more assertive in spreading itself around the garden, the kikuyu is 10 times harder to pull out - nasty stuff!