Question
I just planted a prairifire crabapple tree, 2 weeks ago. the leaves are turning yellow, starting at the inside. what have I done wrong?

Answer
Sharon:
Based on the time frame that you indicated, I would not suspect a bona fide infectious disease, but rather an unfavorable environmental situation related to the establishment of a new transplanted plant. This may be called "transplant shock", that crucial time after planting and before the plant gets firmly established in its new surroundings.  There could be multiple factors that come into play here. Trees and other plants need TLC for the first few weeks. Trees need to be watered in well at planting. By this I mean the hole is filled with water to bring soil in contact with the roots. If a root comes in contact with an air pocket, it essentially stops growing. So, a real good drink at planting and then generally a good deep soaking once per week for 3-5 weeks.  You may have to adjust depending on your soil. Sandy soils a bit more, and clays, a bit less. Avoid drowning- I do not recommend. These types of things lead to stress that often shows up as leaf discoloration and drop. Most folks do not recommend fertilizer at planting, but after the tree gets established. I would suggest making sure the soil is moist, but not too wet or dry for the next few weeks- just some TLC.

Depending on the tree- if in a pot, planting can be done most anytime of the year. In a burlap wrap/bag or bare root, in my part of the world, late fall thru early spring is best, this is when the tree has slowed down during the colder weather.

Keep an eye on the tree, don't give up now. It may drop some leaves, but just monitor the water situation.

Let me know how it looks in a month or two.

Regards
Steve