Can Compost be Used as Mulch?

After a recent Gardening Australia episode informed me that compost was NOT suitable as a mulch, I was faced with a new reality requiring a paradigm shift from my current thinking.

Or did I?

Are GA reporters infallible and can their advice be trusted without question? Hmmm… it was time to think this one through a little more.

See, the problem is that I’ve always used compost as mulch. Not just mulch though as I use it for soil conditioner, potting mix, seed raising mixes, compost tea and even dessert if there’s nothing left in the pantry – if you’re not a gardener you won’t understand that last use.

And now GA is saying that it shouldn’t be used as a mulch but rather a conditioner only and then covered with a coarse material mulch. The reason: “…using a finer based mulch is it absorbs moisture and can also form a seed bed for weeds”. Okay. I can live with that. If weed seeds are transferred around the garden either by wind or through birds or insects dropping them then it is plausible that they could begin to grow in the compost mulch.

But what are the chances of that happening on a large scale. Fairly minimal, I’d suggest. Sure, if you live next to a neighbour who ONLY grows weeds then that possibility is increased. Yet for most of our gardens the beds would be completely covered with compost mulch thereby inhibiting any weeds growing let alone being dispersed.

After a few weeks of rattling these thoughts through my muddled mind I realised that my practice of using compost as mulch probably wasn’t a bad one. Then, in yesterday’s Sunday Times, lo and behold the Garden Gurus have an article titled “Six Ways to Keep Your Plants Alive This Summer”. [The Garden Guru’s is partner hosted by Neville Passmore – an ex-GA journalist].

Their number one point:

Apply a thick layer of dense compost-like Biowise or composted garden humus over all garden beds. Composted organics are the best mulch because they hold moisture and nutrient longer.

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