Brown Edges on Petals & Brown Edges on Leaves

Abraham Darby with Thrips

Abraham Darby with Thrips

What causes brown edges on rose petals?

Brown edges on petals are usually caused by thrips. Thrips are tiny chewing insects that are about 1/16 inch long, with a diameter the size of a hair.

Thrips are usually found on light colored roses, whites, yellows and pinks. The female drills a small hole in the bud at the sepals and lays her eggs in the developing petals. The egg hatches in a few days as the bloom matures, providing the larva juices to grow.

Thrips cause the flower to be deformed. Sometimes they prevent the flower from opening. The petals appear to be brownish around the edges.

Thrips can be controlled by spraying – only the bud – with a good systemic spray.

Brown edges on the leaves are usually caused by salt burn. This is a common problem caused by a buildup of salts in the soil. Salts can accumulate from ineffective watering practices or if an excessive amount of fertilizer is used.

You can avoid this problem by periodically watering slowly and deeply to leach the salts past the root zone.

Always follow the instructions carefully on fertilizer containers and do not over apply. Always water thoroughly before and after fertilizing to help prevent burn.

I hope this helps to answer your question.

-Marylou Coffman, ARS Judge, Vice Chairman of PSWD, and Consulting Rosarian

Below is a picture of the same Abraham Darby rose without thrips:

Abraham Darby