by Nanette Londeree, Master Rosarian
SYMPTOMS
Paling (lighter green to lime-green color) or yellowing of interveinal (between veins) tissue
Leaves that are pale green, yellow, or yellow-white
Portions of the plant stunted or fail to produce flowers
Discolored leaves more prone to scorching and leaf diseases
CAUSE
Chlorosis, yellowing of green plant foliage due to a lack of chlorophyll development
Affected plant has little or no ability to manufacture carbohydrates due to chlorophyll insufficiency
OPTIMAL CONDITIONS
Low levels of iron in the soil
Soils with pH above 6.5 bind up the iron and make it unavailable to the plant roots
High concentrations of limestone (calcium carbonate) make the soil more alkaline (higher pH)
Roots that are damaged by a lack of oxygen in overwatered or poorly drained soils
Extreme soil temperatures and conditions that restrict air movement into soil like plastic sheet mulching, compaction
Soils that contain high levels of zinc, manganese, phosphorus or copper
TREATMENT
Prevention:
Maintain soil pH at 6.5 or lower through use of soil amendments
Maintain good drainage
Don’t overwater
Elimination:
Lower soil pH by incorporating acidic amendments such as peat moss or leaf mold
Add chelated iron to soil
Correct watering method / frequency
Correct drainage problem or move plant to pot or raised beds
GOOD GUY / BAD GUY?
This is a bad guy; the more chlorotic the plant the more severe the condition
If not corrected it can cause death of the plant