Hello! I have a rather odd question. We live in a newly constructed townhouse with a very small backyard. We back very closely onto a rather unattractive 2 storey house. In order to provide a more pleasant outlook and to provide more privacy, I’d like to plant several blue arrow junipers along our back 6ft high fence line. Could I plant the junipers in a constructed ‘box’ (no bottom) 2.5ft deep and 2.5ft high along the fence? This would boost the newly planted junipers up and above the fenceline more quickly than waiting years more for them to grow to a decent height to provide the privacy we’d like. We’re seniors and might not have the time to wait years for the plants to reach an effective height! ;)
Thanks very much!
Thank you for contacting the Toronto Master Gardeners. I think the new constructed box that you have described as the planting location you are considering for blue arrow junipers (Juniperus scopulorum ‘Blue Arrow’) will work well, as long as it is in a spot that gets the full sun that is preferred by these trees. Blue arrow junipers are fairly low maintenance. They grow at an intermediate rate ( 6-12 inches annually), to a mature size of 12-15 feet in height and 2-4 feet (usually closer to 2 feet) in width. You will need to consider their mature size when determining how many trees you will need and the size and placement of your box eg. proximity to your fence. Blue arrow junipers are adaptable to different soils but do require good drainage / cannot tolerate wet feet.
The box that you are considering sounds like a tall (or containerized) raised bed, meaning that it is taller than the usual height for a typical raised bed intended for growing vegetables. One of the advantages of a raised bed is that it provides increased drainage. On the flip side, it will dry out more quickly since it is above ground, so it might need additional watering; however blue arrow junipers are pretty drought tolerant. Another benefit of a raised bed is that you will have more control of the soil characteristics, including soil structure. However you will need a lot of soil (perhaps a financial consideration). You might also need to remove (or smother) any grass that might be in the location for the new box (additional labour).
Hopefully this information is helpful as you decide what to do in your backyard. Good luck with your project !
For further reading:
http://plants.connon.ca/11100004/Plant/1803/Blue_Arrow_Juniper/
Jan 16, 2022