is the end of November too late to plant emerald trees that are in pots and are 5 feet tall. Location London Ontario on well drained sandy soil .
Thanks for contacting the Toronto Master Gardeners. The best time to plant Emerald Cedars (Thuja occidentalis ‘Smaragd’ or ‘Emerald Green’) is mid to late spring when the soil has warmed up a little. The second best time is during the cool days in the early fall, so the plant has a few months to establish some roots before the ground freezes up. I think planting your cedars at the end of November won’t allow for a long enough settling in period.
If you have already bought your cedars, I suggest that you leave them in their pots and move them to a sheltered spot eg. the garage for the winter. It is important that Emerald Cedars are well watered right up until the soil freezes. If the roots thaw out during the winter, water the cedars every couple of weeks to ensure that the roots stay hydrated. Alternatively, if the ground is not yet frozen you could consider digging holes and sinking the pots into an area in your garden where they will be protected from winter winds, without much winter sun. The pots will be better protected if they are submerged in soil rather than leaving them exposed to the winter weather. Again, you will need to keep them well watered until the ground freezes.
Emerald Cedars dislike dry, sandy soil, as well as excessively moist clay soil. They prefer moist, organic, well drained soil. So in the spring when it is time to plant them, adding some compost to your sandy soil and mulching around them (but not up against the trunks) will help to maintain the appropriate amount of moisture in the soil. Emerald Cedars prefer full sun.
Here is a link from the Missouri Botanical Garden that provides information about Emerald Cedars :
https://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?kempercode=m550
The Toronto Master Gardeners get a lot of questions about these plants, and there is lots of information about them on our website. Just type ‘emerald cedar’ into the search box under ‘Find it Here’ on our home page.
Good luck with your cedars !