How compostable is your coffee lid?

Our awesome local café, Laundromat, has started using bio-plastic lids on their takeaway coffee cups. They’re made of something called PLA, which stands for polylactic acid; it’s made from corn or sugar cane and is supposed to break down naturally – but I’ve always wondered how seriously to take this claim.

I mean, are we talking days? Weeks? Years to break down? To find out I took a couple of lids from our lovely barista and buried them in our worm farm. Check this out:

As you can see, the normal plastic lid looks exactly like it did on the day it was buried, while the PLA lid is noticeably degraded, cracked and brittle – though it has hardly turned into soil. Our worm farm, I should point out, is about the most perfect composting environment you could imagine. Vegetable scraps turn into rich, black soil literally in days – while this thin ‘compostable’ lid has survived more than a month mostly intact.

What do you think? Is calling it ‘compostable’ just greenwash, or do we simply need to be realistic about how long these things take? I have to say I’m shocked at how perfectly pristine the normal plastic lid is – and these days I’m inclined to think that any kind of biodegradable plastic must be better than packaging that lasts forever.

Interesting huh? Anyway, I’ve reburied both lids and will unearth them every few months to show you how they look – I’ll keep you posted.

In other developments we’re very proud to bring you another fine issue of Green Ideas magazine – this time themed around great ideas for summer. There’s a step-by-step guide to making your own refreshing craft beer, and 21 tips and gadgets for greener camping. We show you how to create an unkillable garden (handy if you’ll be neglecting yours over the holidays) – and find out why baby boomers are taking up sweat-free cycling on electric bikes.

Plus we have a Summer of Giveaways special, with a crazy $3,900 worth of prizes to be won! Click here to enter the competitions.

Finally, if you’ve been watching the excellent Shark Man TV programme (Saturdays, 4.30pm on TV One) you’ll want to get the story behind why this chilled out Kiwi guy loves swimming with the world’s ultimate predators. I promise it won’t put you off the beach over Christmas!

Happy holidays,

Greg Roughan
Editor, Green Ideas magazine

Like what you see? Subscribe for a year for only $23.50.