In The Grow Question and Answer — Common Winter Injury Symptoms We Saw this Spring
June 6, 2018
Q. I have a yucca tree that is 5-6 years old. What was a small plant has become a mature tree. I transplanted my yucca to a larger pot last summer. There was a significant explosion in growth. If you look at the picture you can see the growth.
Unfortunately, it suffered through this past winter indoors. Much of the new growth witnessed last year is gone. Please see the attached photo — I think it speaks for itself. The green foliage died over the cold winter, yet you can see the growth shoots that remain.
Do you have a suggestion for helping this tree? — R.M., Tippecanoe County
A. It’s not too surprising that there was more dieback that usual this year given the extreme cold conditions we experienced this winter. Even indoors in unheated garages got colder than we typically expect. The new green growth at the lower part of the plant looks great. Just cut off the brown, dead stems and the plant will immediately look a lot better! Be sure you cut back to just above where there are healthy looking new shoots.
Q. I planted a Weigela ‘Wine and Roses’ shrub about five years ago and it has done well in previous years. But this spring, there seems to be a lot of dead branches and only sparse flowers. Is there something I can do to help this plant? — N.L., Zionsville, Indiana
A. Weigela is only marginally hardy in our hardiness zone, and this winter was quite harsh. A number of our readers report similar symptoms on their shrubs this year. But some degree of dieback is not unusual in our area any year. However, cold injury can make the plant more susceptible to further damage from infectious disease.
Because Weigela blooms primarily from buds that formed on last year’s growth, winter dieback will reduce flowering. They do sporadically bloom from the current season’s growth, which you encourage by pruning after spring flowers fade.
You can prune back the dead branches anytime, be sure to cut back to a healthy, leafy branch just above the collar (ridge) of bark where the branch is attached.
For more information see Pruning Ornamental Trees and Shrubs Purdue Extension publication HO-4-W.