Did you feed your new plants when you planted them, and keep them well watered, Arch? They do like quite a good, rich soil. With the runners, I just leave mine to root in the soil around the plants, but don't allow more than about 3 to develop on any plant. Cut off the others, as the main plant will be weakened. You can put the new plants on the runners into the top of pots filled with good compost, and weight them down with a stone or pin them with loops of wire, and keep them well watered. Once the new plants have rooted, you can cut them away from the runner , and move the new plants to a sheltered site for the winter. Only allow one new plant for each runner though, and cut off anything that tries to grow beyond it, otherwise that will also sap the strength of the new plant.
Hope that'd all clear, but I'm sure you could find out more on the net, or from GOYpedia at the bottom of the page. Good luck..Annie

Yes, I did feed - only growmore. Thanks for advice re runners.

Would it be bad if I move the old plants now? I have a better site (less windy) available.