For some people, pollens, grasses, flowers and trees can all be ‘allergens’, causing allergic reactions or hayfever. How bad the symptoms are may vary according to the time of year (this is called ‘seasonal hayfever’) but some allergies occur all year round (known as ‘perennial hayfever’).
Seasonal hayfever plants
Spring hayfever sufferers are usually allergic to tree pollens. But if the problems occur in late summer and autumn, grass and weed pollens are probably the cause.