D. Overstreet of Fort Sam Houston, TX asks:

“My shrub leaves are yellow. What can I do to help my tree survive?”

Well, this is a common problem without a simple answer. Yellowing, often referred to as chlorosis,  is caused by leaves lacking chlorophyll, which gives them their green color and allows them to create food for themselves. Chlorosis can be the result of many different things. Without proper evaluation of the plant and its environment, it is impossible to know which of the following relates to your specific plant (or if the issue derives from something entirely different). I suggest inviting a horticulturist in your area to evaluate the plant in its environment for a proper diagnosis. 

A few things that can cause leaves to yellow:

• This is actually a plant that is supposed to have yellow leaves; some plants are cultivated to have more yellow leaves than green leaves
• Improper planting
  • Planted too deep
  • Planted too shallow
  • Planted with circling or girdling roots
• Compacted soil
  • Too much water
  • Too little water
  • Too little air space
• Pests and disease
• Planted in the wrong place
  • Too much sun
  • Too much wind
  • Too much ice/snow
• Cambium damage
  • lawn mowers nicking the bark
  • Other tears/damage to the bark layer
• Nutrient deficiency or over-abundance
  • Nitrogen is used for greening in plants, but don’t over apply!
  • Other micro or macro-nutrient deficiencies or over-abundance

Thanks again for writing in with your questions. Try exploring the plant closely to see if you can find a solution among the various possiblities above or take a sample to the help desk at your local nursery.