Late or early?

One thing I've noticed since I started recording is that spring and summer flowering plants often have a late second push in autumn, if the weather is warm enough. Many species do this, including: Hogweed, Cow Parsley, Nipplewort, Ragwort, Herb Bennet and Bush Vetch. Other flowering plants seem to flower all-year round, now. These include: Daisy, Dandelion, Sow-thistles, Smooth Hawkbit, Herb Robert and Groundsel. But what do we have when I find a specimen of Hogweed in full flower in January?

Is it early for 2008 or late for 2007? I think the answer is fairly clear: the new stem growth for 2008 hasn't even started yet, so it has to be late for 2007. But what is it trying to do? The pollinating insects are all dead (and won't be back until April/May), so it can't reproduce (and it would be unlikely that there would be another specimen close enough to pollinate anyway). It must be worthwhile, or the plant wouldn't be expending all this energy on making flowerheads. Maybe it's a mechanism whereby it is preparing for all-year round insects as we warm up. What do you think?

Other late-flowering species:

Bush Vetch

Smooth Hawkbit

And just to finish off, a couple of shots of Winter Heliotrope, which only flowers during December and January around here: