This is how you can grind Red Iris Flowers relatively quickly in Pre-Searing Ascalon, in Guild Wars.
The idea is to do a round in Lakeside County starting from Ascalon City.
The flowers spawn in the general areas shown in this map.
You will get 5 flowers in a full round. Fast-travel back to Ascalon City after the last flower and repeat as necessary.
This is the round I've been using.
With bad luck the northernmost flower may spawn outside the North Gates. Being beyond the map travel point, the elusive red flower is rendered unreachable.