Sick Citrus - Ask Extension
Hello, I have Meyer lemon trees that have lost nearly all their leaves, and those that remain have brown splotches on yellowing leaves. I have given...
Knowledgebase
Sick Citrus #369495
Asked October 12, 2016, 12:08 AM EDT
Hello, I have Meyer lemon trees that have lost nearly all their leaves, and those that remain have brown splotches on yellowing leaves. I have given the tree citrus food but n improvement.
Separately, I have a Mexican lime tree loaded with tiny fruit, but the tips of the leaves look scorched - brown and crinkled (3rd picture I uploaded). It's been a hot summer, but I don't see my neighbor's citrus looking this way.
Any insight much appreciated.
Separately, I have a Mexican lime tree loaded with tiny fruit, but the tips of the leaves look scorched - brown and crinkled (3rd picture I uploaded). It's been a hot summer, but I don't see my neighbor's citrus looking this way.
Any insight much appreciated.
Los Angeles County California
Expert Response
It is difficult to assess problems of generally poor health on citrus trees without knowing more about your past care--water and fertilization.
Although you have applied "plant food", I suspect that the amount and frequency is insufficient, because these look like trees that are very depleted in mineral nutrition. I can only guess from the pictures that these are mature trees. As such they need an annual application of nitrogen of about 6/10 to 8/10 lb of actual nitrogen per tree. Using a 13-13-13 fertilizer, as an example, they would need 4.6 to 6.2 lbs applied each spring and summer, divided into 2-3 applications. This will also supply needed Phosphorus and Potassium. Your fertilizer should also contain magnesium and micronutrients as well as N-P-K, and should be broadcast as a granular product throughout the area covered by tree limbs and 3-4 feet beyond.
Fertilizer will only accomplish what it should do if the trees are also being watered properly. Mature citrus trees can withdraw 40 gallons of water per day in the summer when they have a crop, so your watering practices should address supplying 280 gallons of water per week during hot dry periods.
Citrus trees thrive with good water and fertilizer. I suspect you need more inputs of both. You should also consider contacting the University of California cooperative extension system for their recommendations for citrus tree care that may take local soil, water and nutritional conditions into consideration.
Although you have applied "plant food", I suspect that the amount and frequency is insufficient, because these look like trees that are very depleted in mineral nutrition. I can only guess from the pictures that these are mature trees. As such they need an annual application of nitrogen of about 6/10 to 8/10 lb of actual nitrogen per tree. Using a 13-13-13 fertilizer, as an example, they would need 4.6 to 6.2 lbs applied each spring and summer, divided into 2-3 applications. This will also supply needed Phosphorus and Potassium. Your fertilizer should also contain magnesium and micronutrients as well as N-P-K, and should be broadcast as a granular product throughout the area covered by tree limbs and 3-4 feet beyond.
Fertilizer will only accomplish what it should do if the trees are also being watered properly. Mature citrus trees can withdraw 40 gallons of water per day in the summer when they have a crop, so your watering practices should address supplying 280 gallons of water per week during hot dry periods.
Citrus trees thrive with good water and fertilizer. I suspect you need more inputs of both. You should also consider contacting the University of California cooperative extension system for their recommendations for citrus tree care that may take local soil, water and nutritional conditions into consideration.
Thank you very much. Those guidelines for Redding and water are very helpful.
Much appreciated!
Much appreciated!
