Enschede lies in the Twente hedgerow landscape, exceptionally rich in trees by Dutch standards. Not continuous forest like the Veluwe, but a fine mesh of hedgebanks, tree lines and small copses between the pastures — oak, alder, hazel and birch. For a hay fever sufferer that means a source which is not in one place but all around the city, from the Lonnekerberg to Twickel and the Aamsveen.
The second characteristic is the German border. Enschede is about as far from the coast as you can get in the Netherlands, so the dilution by clean sea air that the Randstad regularly receives is largely absent here. The air is more often continental: drier, warmer in summer, colder in winter, and carrying supply from the wooded Münsterland under an easterly. That makes the peaks sharper here than on the coast. Between the hedgerows lies farmland, so the grass season from May to July applies in full.