Allotments 4 All

We have creeping cinquefoil in our lawn, which has crept into the flowerbeds.  I'm at a loss as to how best to tackle this problem.  Should I use Verdone Extra Lawn Weedkiller to tackle the problem in the lawn, then lift all the plant/bulbs and dig out the infestation in the beds.  And if so what is the best time of year??  I would be grateful for any ideas as I have spent most of the year digging it out every month or so....