Pollen Count & Forecast for Hillingdon

Hillingdon’s spring allergy profile is dominated by Birch (March-April) from mature park trees like those in Ruislip Woods; Oak pollen follows (April-May) across borough green spaces. Summer features ubiquitous Grass pollen (May-July), originating from extensive local meadows, sports fields, and the River Colne/Grand Union Canal banks.

The borough’s urban-fringe geography and sheltered residential areas can locally elevate pollen concentrations; dry, windy conditions enhance airborne dispersal. Autumn-winter sees Mould spore prevalence, linked to damp leaf litter and decomposing vegetation in wooded areas.