"Alan Holmes" wrote in message
...

I've been using some 2/3 year old compost, but it seems to be full
of weed seeds, I've tried putting some in the microwave but I'm not
sure it's been detrimental to the compost.

So what is the best/simplest way of getting rid of unwanted weed
seeds in compost?

How do commercial suppliers do it?

Best to ignore them, use your compost in the normal way and deal with
any weeds as they emerge.

Dealing with weeds is a never ending process because they arrive from so
many different sources as shown in this interesting site.

http://www.nwcb.wa.gov/education/control.html

Regards,
Emrys Davies.