Rose Glow Barberry

(Question)

Hi, I live in Toronto (west end near Dundas and Dufferin). I have a 2X4 space in my garden that gets full sun (mostly afternoon). I just planted a Rose Glow Barberry (Berberis thunbergii). Beside it are a lilac tree and on the other side some raspberry canes. Now I am reading that Japanese barberry plants are invasive and can attract ticks. Is this true? Should I make a different choice for this spot? Thank you.

(Answer)

According to the Ontario Invasive Species Awareness Program, Japanese barberry Berberis thunbergii is an invasive shrub native to Japan that was introduced to North America in the 1870s at the Arnold Arboretum in Boston. Because of its bright berries and leaves it has been widely planted across North America as an ornamental plant.

As you know having planted it, it is densely thorned.  It is a prolific seed producer well into the fall which birds spread widely.  Branch fragments can readily root to form new shrubs which can result in it forming dense thickets. It is also capable of becoming established in a variety of habitats, including areas with partial sunlight and deep shade.

With regards to barberry harboring ticks, Entomology Today states that the ground cover creates a “humid microclimate conducive to tick proliferation”.  A study conducted found the larger the number of this plant in an area, the higher the incidence of Lyme disease carrying ticks.

There are many native alternatives to Japanese barberry, including dwarf fothergilla (Fothergilla gardenia), highbush blueberry (Vaccinium corymbosum), New Jersey tea (Ceanothus americanus) and Virginia sweetspire (Itea virginica).  You might enjoy having a look at the “Grow me Instead” site at https://www.ontarioinvasiveplants.ca/wp-content/uploads/2020/04/Southern-Grow-Me-Instead-1.pdf

Should you remove your barberry?  It is ultimately up to you.  I understand why you chose it as it has a beautiful colour, however I would encourage you to have a look at the native alternatives which tend to do very well here and support our ecosystem in a positive way.