There are several reasons to be conscious of high pollen flowers that produce allergies and cause people to suffer when the whether outside turns from cooler to warmer. Warmer temperatures bring with it more moulds and allergens from the pollen in the air which is produced by flowering trees, shrubs and plants. An owner of a house that wishes to update their landscaping around their home should consider purchasing and planting no or low pollen flowering trees and vegetation if they suffer from seasonal allergies.