Unblemished lush green leaves are a good indication that our plants are thriving, well watered and happy. Leaf abnormalities, on the other hand, are often signals that our roses are under attack or in distress. Causes are varied and can be due to environmental problems, chemical toxicities, mineral deficiencies and fungal and viral pathogens. A plant will respond to these conditions with symptoms that include wilting, spotting, color irregularities or misshapen leaves. Pests leave telltale signs of their presence with damage such as distorted leaves, webbing and holes. Identify trouble by learning to read your roses’ leaves, and then take action when appropriate.

Environmental Problems

Yellow or Brown leaves can have several very diverse causes:

Yellow leaves that drop can be a sign that there is not enough oxygen in the soil. This is often caused by over watering or inadequate drainage. On container plants, make sure the drainage hole is not plugged, and in very clay soils, consider growing your roses in raised beds.

On the opposite spectrum, yellow, drooping and wilting leaves, or leaves with brown tips can mean that your plant needs more water.

Don’t panic if your otherwise healthy and vigorous plant has some yellow and brown leaves. It is normal for old leaves to turn yellow, then brown and drop.

Leaves that are Distorted and Deformed. Phytotoxicity is the toxic effect on a plant due to compounds such as pesticides, herbicides, metals and salts.

Needle-like shoots and leaves are an indication of glyphosate (Roundup) damage. Even the tiniest amount of spray drift can injure your roses.

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