Many landscapers and gardeners use flowering shrubs for ornamental purposes on commercial sites and private homes. There are several flowering shrubs that cause havoc with people’s allergies once the warmer months arrive. Most allergies to plants are due to high pollen counts on the plant’s flowers and foliage. It is best to avoid planting these types of flowering shrubs if you suffer from allergies; hypoallergenic plants are available for gardening uses.
The common juniper (Juniperus communis var. depressa) is an evergreen shrub that flowers with billowy flowers. It is a wide bush that grows to be 3 to 6 feet in height. The flowering shrub spreads out to be several yards in diameter and has a circular pattern. The foliage has sharp pointed needles and during May and June it grows a tiny, waxy bluish-white fruit. This plant is known to cause problems with people who suffer from asthma and allergies.
The white mulberry (Morus alba L.), also known as the fruitless mulberry, is a perennial shrub; this plant is also classified as a tree. It blooms with green flowers in the spring and grows purple seeds during the spring and summer. The white mulberry is listed by the University of Arizona as causing allergies to worsen due to high pollen in February and March.
During the months of April through June the glossy privet (Ligustrum lucidum "W.T. Aiton") is a contributor to allergies for people in the Southern regions of the United States. The glossy privet is a perennial flowering shrub and tree that has a high pollen count. This plant grows tiny white flowers that appear in clusters with shiny green foliage. The seeds of the glossy privet are shaped like cashews and are a light caramel color.
The Russian-olive (Elaeagnus angustifolia L.) is classified as a shrub or small tree with thornlike leaves covered in silver or russet colored scales. After planting it takes about three years for this plant to flower; it blossoms with four-petaled yellow blooms that have a strong fragrance and appear in June and July. When the flowers wilt they are exchanged for clusters of silver-colored grape-size fruit. The Russian-olive is a native plant to Southeastern Europe and Western Asia; however, it can be found growing throughout Central and Western United States. According to the University of Virginia, this is a common plant that aggravates allergies.