Posted: 13/01/2013 at 23:51
Now, particularly before a frost, isn't the best time to dig over veg beds in prepararton for spring planting and unless you know what the weeds are, rotivating the area would break up the weed roots and spread them over a larger area.
It sounds like you are able to do heavy work and are keen to prepare the allotment for spring planting. There are different ways of approaching this and I'm happy to be wrong. but you could strim off the weeds and cover the area with either old carpet or black plastic. This will serve two purposes, it will restrict the growth of weeds and warm up the soil come spring.
Depending where you live, late March would be a better time to start preparing your soil for spring planting.
You've missed the autumn window when veg growers would add fertilizer to beds and it's a matter of preference, some growers wait till March to add fertilizer. Clay soil benefits from adding humus to the soil by way of manure. Manure needs to be well rotted though before it can be added to your veg beds, in autum it can be obtained free from local farmers and then needs to be stored for several months to break down, an alternative would be mushroom compost but this would need to be double dug in, to improve the soil and you would need to wait until March time.
Not sure if I've answered your question but others maybe able to help further.