The message
from Dave contains these words:

So really its not worth buying cut flowers in the winter then, trouble
is they wont allow me to use artificial flowers. Problem is I always
promised my late wife that I would always have flowers at her grave,
so I suppose its just a case of buying them more often in the winter.

During winter, perhaps instead of cutflowers you could use various
small pots of winterflowering plants, the kind that are sold quite
cheaply in B and Q, garden centres and garages etc for tubs and window
boxes; such as outdoor cyclamen, primulas, daisies, little narcissi,
snowdrops and tulips, small pernettyas with berries on. These would be
much more frost resistant than a water filled vase of flowers and the
flowers should last longer in winter than cut ones. You could take the
vase home for winter, and just slip the plastic pots inside a small
heavy closefitting stoneware pot (it will need a drainage hole in the
base) to sit in place of the vase. This will stop the wind blowing them
over and the overall effect will be the same as the vase.

HTH

Janet.