How can we save a Stewartia tree where the upper half is dead?
We have a 12-foot tall Stewartia tree that has done well and flowered every year…except for this year. The upper half is dead. How can we save it?
Stewartia is an awesome tree for year-round interest and a relatively recent addition to the Maine landscape. Technically they are only hardy to Zone 5A but recent years have trended warmer in most areas. Unfortunately the midcoast was severely affected by the midwinter cold snap and many plants were affected by bud dieback. You will know just how much when the tree blooms in July.
Since the tree is only 12′ high you should be able to do the cutting back needed to reshape the tree and it will then continue to grow to its mature height of 20′ + over the coming seasons. But don’t start cutting yet.
Here is a link to a video on pruning ornamental trees, the hardest part is waiting until next winter (or at least November) to do this. I am sure that the tree looks dead at the top and part of it probably is, but take the time this season to see what happens to the tree before you start cutting it back. Cutting it at the top during the growing season will produce lush growth in clumps and tax the already stressed tree. So please be patient. As the season progresses tie yarn or ribbon to the branches that are dead so you will know where to cut when the plant goes dormant. If half the tree has died, then prioritize your cuts as you don’t want to take more than 25-30% of the tree at one time, so you might have to hard prune again in the next season.
This summer, really baby the tree-make sure it gets steady moisture (1-2″ of water for the entire width of the dripline). Consider doing some fertilizing of the tree but be prudent. This is NOT a case where a “little is good so a lot must be better” In this case, for your tree nothing, is better than too much when it comes to fertilizer. If you have other questions, my contact info is below.