We have a Yew hedge around the house that’s probably 5 years old. Given these are poisonous to cats, dogs, and humans, we are considering replacing them.
We would like to replace part of the hedge with blueberries.
As all part of Yew plants contain poison, do you recommend any special soil perp, such as tilling the soil and removing all the remaining Yew roots etc.? Most large roots will be removed with the Yew plants but wondering about the parts that will break off and stay in the soil.
Thank you for contacting the Toronto Master Gardeners.
According to Government of Canada:” English yew (Taxus baccata) is an introduced ornamental shrub that is hardy in the warmest parts of Canada. This shrub has caused poisoning and death in cattle, horses, and humans. Ingesting leaves, bark, or seeds can cause poisoning in all animals. The fleshy fruit pulp is considered to be nontoxic (or low in toxicity). Taxine, a complex of alkaloids, is found in the plant. Children should be taught not to eat the fruit or seeds of this plant. Animals should not have access to the shrub or clippings of the branches (Cooper and Johnson 1984, Feldman et al. 1987).”
We know that all above ground parts of the yew are poisonous the question which remains is do the yew roots contain the same level of toxicity and whether that level of toxicity remains in the root system for an extended period of time once the tree has been removed. According to PennState University: ” Our conclusion is that the toxic alkaloid taxine is in fact present in yew root as it is in above-ground components of the tree, and that it remains present in the root material for as long as that root material remains undecomposed.”
Even though there are toxins present in the yew roots there is no evidence found in literature that the toxin leach out into nearby plants.
There is an excellent article on Gardenmaking.com on growing blueberries. It states: When growing blueberries…
“Look for a spot with plenty of sunshine, at least six hours per day, and decent, well-drained soil. Blueberries have shallow, fibrous roots systems and cannot tolerate wet feet or heavy, clay soil. If the soil is poor or not well drained, consider planting in raised beds. Blueberries also need slightly acidic soil, with a pH in the 4.5 to 5.2 range. If you don’t know your soil pH, it pays to get a soil test and make any necessary corrections before you plant. Applying elemental sulphur to the soil is the most common way to lower pH, but it’s a biological process and will take several months to take effect. If possible, acidify your soil the autumn before you intend to plant.”
The Ontario Ministry of Agriculture and Food has an excellent factsheet on how to grow blueberries in the home gardens https://www.omafra.gov.on.ca/english/crops/facts/90-046.htm . You will find a lot of very useful information in this factsheet.
There are several ways to go about having your soil tested:
Simple soil testing kits to test the soil for pH, nitrogen, phosphorus and potassium can be purchased at any garden centre.
The Ontario Ministry of Agriculture and Rural Affairs (OMAFRA) has a list of accredited soil testing sources www.omafra.gov.on.ca/english/crops/resource/soillabs.htm
In addition the City of Toronto Public Health Department has published an excellent Guide for Soil Testing in Urban Gardens. https://www.torontomastergardeners.ca/wp-content/uploads/2012/02/Guide-for-Soil-Testing-in-Urban-Gardens.pdf
I hope you have good luck and lots of blueberries this summer.