I've used multipurpose compost in the past any make will do, also leaf mould that I've composted behind the garage.

There are inorganic mulches you can use too - slate chippings, gravel, pea shingle, decoratively coloured chippings, glass chippings, even rubber pellets, but any weed mulch must be at least 2 inches deep and preferably 3. Organic mulches such as bark chips, composted manures, garden compost are better for the soil and your plants though - they degrade over time and add humus to the soil, but you will need to keep them topped up.

I believe Strulch is effective too, and more attractive then bark chippings.

its just a sales pitch to sell you it . even with a membrane and 3" of what ever mulch you get biodegradable stuff on it . if that happens then weeds happen .

after all a weed is a plant in the wrong place .

I agree. Hoeing is the best anti weed in the long run.
If you use the inorganic ones Bamboo mentions what happens when you want to dig up a plant or put in a new one?

Never heard os Strulch Canalhopper - it looks very useful!

I saw Strulch in use in a beautiful garden I visited under the NGS scheme. It looks good, far better than bark chippings, and the owner thought it was good. If it was good enough for her, it's certainly good enough for me!

In the pic on Google it looks rather like dried hay - did it look ok on the ground then?

it still sounds like a gimmick to me .