Sky Pencil Holly Died

Question

We removed a large crepe Myrtle 5 years ago. Root ball was left in the ground and eventually died off. We dug out the dead crêpe myrtle root ball and backfilled with existing yard plus added some new soil and compost in Spring 2021. I planted a 3 foot tall Japanese sky pencil holly in that locatIon, along with 15 other sky pencils along fence line. They are all spaced 4 feet apart. The sky pencil holly I planted where crêpe myrtle root ball had previously been, died within a few months. I replaced dead shrub in early fall. It died too, during the winter. All the other sky pencils are alive. I used same new soil and compost when planting the other sky pencils. However, I used more soil/compost due at crepe Myrtle root ball spot. Why are the sky pencil dying at that one spot? We did not use chemicals to kill off the crêpe myrtle root ball. Maybe that area has more dirt/compost and retains more/ too much moisture? Or did crepe myrtle decomposition alter area? Crepe rootball left a 3’x3’ wide and 2’ d hole.

Answer 1

Unfortunately, your photos did not come through. I am unable to assess the situation.

There aren't many diseases shared between the two, which leads me to believe that the soil in that spot is not suitable for plant life.

An extension service in your area can be of assistance to find out what is wrong with the soil by means of a soil sample. If you have a microscope and stains, then you can test for pathogens, yourself. Kits for pH and nutrient contents can determine if the nutrient content of the soil is off.

Here are some articles that will help:

https://www.gardeningknowhow.com/extension-search

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-moisture-in-plants.htm

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/testing-soil.htm

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/soil-ph-plants.htm

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/test-soil-for-pests-and-diseases.htm

https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/making-sure-soil-drains-well.htm