The leaves on my oriental lilies ('Stargazer') are turning yellow from the top down. Some have developed brown spots. Leaves further down appear s...
Oriental Lily Turning Yellow #461699
Asked June 12, 2018, 11:07 AM EDT
The leaves on my oriental lilies ('Stargazer') are turning yellow from the top down. Some have developed brown spots. Leaves further down appear splotchy. It's been very wet this Spring and Summer. The lilies face south and west, though it's a rather shady location. I've had them for a few years; they survive and have some blossoms though not thriving as they would in a sunnier location. I knew this would be this case when I planted the bulbs - wanted a little color in this shady garden.
There are two viruses that are common to lillies: 1. Lily Symptomless virus and 2. Cucumber Mosiac Virus. These viruses are transmitted by aphids. Lily leaves develop white to yellow mottled, striped, or flecked pattern (the pictures you provided show yellowing in a stripe pattern). There is no effective treatment for viruses, therefore infected lilies must be removed and destroyed. Aphid management is possible with mechanical removal using a garden hose or insecticidal soap - follow instructions on package.
General guidelines for growing lilies: slightly acidic, well drained, fertile soil in full sun to partial shade; regular watering of 1" weekly with soaker hose to avoid wetting soil; use layer of organic mulch to retain consistant moisture.
This work is supported in part by New Technologies for Ag Extension grant no. 2020-41595-30123 from the USDA National Institute of Food and Agriculture. Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture.