The Rockdale Gardener

Gardening Posts From Rockdale Cooperative Extension

Problems on Cedars This Spring

Deodar cedar needle cast

Needle cast on a Deodar Cedar

I have gotten many calls about various cedars/cypress/pine trees (Deodara, Italian, Leyland, etc.)  turning yellow or bronze and dropping needles. There are several things going on right now that could be the problem:

Spider mites – cool season spider mites like Southern Red Mite thrive in cooler temperatures. Our relatively cool dry April has given these sap-sucking critters the perfect conditions for replicating. They damage needles by sucking the juices out of the leaves causing them to turn bronze then brown.

Needle cast – needle casting diseases cause the needles to turn yellow or brown before they fall off. These fungi thrive in cool wet weather. Trees in too much shade do not dry out quickly in wet weather and the fungi are able to grow.

Root rot – most conifers do not like ‘wet-feet’ or being in soil that is too wet. Root rotting fungi live in the soil and are able to attack excessively wet roots. Some plants are more susceptible to attack than others. Most conifers are very susceptible.

Bottom line : conifers need full sun, adequate drainage and good  fertility to help prevent problems.