My beautiful knot garden of hick’s yews are dead!

(Question)

My neighbour did a total landcape redesign of his front walkway and stairs which boarders very closely to my beautiful 12 year old well established and healthy hicks yews. I covered them with burlap this winter as i always do to protect them from salt and cold and when I took off the burlap pretty much the whole side that borders onto their property is yellow and dead. I recall that they had a cement mixer and plenty of water draining into our soil right beside these yews for at least 8 weeks and the ground was always wet with runoff water. Could this have killed these yews? I have a good relationship with these neighbours and think that their contruction company should have taken better care to make sure that the runoff water and location of their cement mixer shouldn’t have been so near to my well established knot garden which is now totally ruined. I can’t even imagine what the cost would be to repurchase and replant this garden not to mention how ugly my once beautiful front knot garden was. Can you please advise?

(Answer)

It is always difficult when there are issues between neighbours who differ in what is suitable for their properties, as well as considerations regarding gardens and trees.  As you say it is always important to keep cordial relations when these differences of opinions sometimes arise.

Yes, I believe that these yews may be dead.  You can double check by doing a thumbnail scratch on branches to see if there is some green underneath the brown exterior which would indicate, live growth.  If there is none, then it is likely the plants are dead.  Most shrubs that exhibit dieoff to such an extent would require constant assault.

This could be from weather, such as the prolonged cold, wind and ice that we experienced in Toronto and Southern Ontario this year.

Alternately, this could be caused by an upheaval from activities such as; changes in grade adjacent to the garden, root disruption & damage from digging, water source re-direction away from plant roots from new hardscaping such as a patio, soil compaction from construction, root drowning due to too much water and not enough oxygen in the soil, lack of available nutrients, soil contamination, to any number of other reasons.  Having the soil tested for available nutrients as well contaminents such as salt, might also be a good idea as this might shed some light on the subject.  Judging from the location of the dead plants, I would generally rule out the weather as the rest of the knot garden looks fine.

Even so, when examining your photo, it seems that your neighbour’s hedge along the garden looks damaged as well, as I think I can see yellowing foliage there too.  For both sides of the garden to exhibit this dieback, the cause could be the runoff – constant soaking (8 weeks) can drown the roots and kill the plant.  It might be worth a friendly discussion with your neighbour to see what can be done.  If they used a reputable and insured contractor, then the contractor may be willing to replace the plant material, if it is not covered by a one or two year nursery guarantee.

It may be hard to pinpoint exactly what killed your shrubs, as it might well be a combination of factors including weather, but if the contractor is not forthcoming, the neighbour might be willing to share some of the cost of replacements.  It’s worth the friendly discussion anyway and if you have photos from the construction time, it may help your cause.

Good luck.