Aphids seem to overwinter on our parsley, too.

Then they pass on to the strawberries!

To deal with them organically you need to take your time and go over the plants carefully, either squishing or spraying. The soap/ oil mixture needs to actually touch the aphids and you will need to do it every week until things improve. If there are ants around - which guard the aphids in order to harvest their sweet excretions - it's much harder to keep things under control. As Nicos says, you need to feed the plants too to help them keep going.

Be persistent - that's the best advice I can give.