Pests and Diseases
Articles about pests and diseases of lilies, including aphids, spider mites, lily leaf beetle, botrytis and more.
Although I have never (in 20+ years of growing) seen an aphid on a lily growing in the ground here, I certainly have seen them occasionally on potted lilies. I do not consider them much of a threat at our location, but I realize there are many people who do consider them one of the worst pests of lilies.
Probably the most common disease for lily growers, botrytis is a fungal disease which affects the stems, leaves and in extreme cases, the flowers and buds of lilies as well. It is not restricted to affecting lilies, it affects a wide variety of other plants and crops as well, such as canola and annual bedding plants.
Below is a copy of the information found in one of our old catalogs regarding control of Botrytis - it periodically runs rampant throughout gardens around the world, when favourable weather conditions persist. It can return again the next year if cleanup is not done properly.
Have you ever seen damage similar to the photo on the left in your lilies? Were you worried or wondering what might have caused it? Speckled yellow, wilted foliage at the leaf tips, turning to brown in some cases, but in almost every case the damaged area remained pliable rather than becoming dry and brittle. Another curiosity to me was the fact that the damage was not seen from stem to tip in most cases. Sometimes it was from the tip down only a few cm, other cases it was extensive, covering up to 30 cm of stem. Often it was found in the middle of the stem with no visible damage above or below that point. In most cases, the plant continued to grow and appeared to flower normally.
MAY 2, 2007
It is with a heavy heart that I must report that the dreaded Lily Leaf Beetle is alive and confirmed to be in Alberta. Recently, I was contacted by a lady in Airdrie who described in detail the beetle, larvae, and the swift and destructive damage to her lilies, as well as to her neighbors lilies over the past 2-3 years. She related how she handpicked hundreds of beetles last summer and had tried every known organic method of control with no success.
Please read the article in this link, written by Crystal Ernst. Crystal is, in my opinion a leading researcher (and Canadian too!) on this pest. She has been the guest speaker at a few seminars to lily society members in North America and provided some useful insight into the habits of the lily leaf beetle.
A bug to strike fear in the toughest of lily growers!
We are fortunate enough to grow in an area where the lily beetle has yet to make an appearance, and we are extremely thankful! We have much reason to be so thankful as this dreaded little beast can do an incredible amount of damage to huge populations of lilies in a very short time!
A bug to strike fear in the toughest of lily growers and gardeners!
We are fortunate enough to grow in an area where the lily beetle has yet to make an appearance, and we are extremely thankful. We have much reason to be so thankful as this dreaded little beast can do an incredible amount of damage in a very short time!
Telltale yellow speckling of the leaves is the first noticeable sign of spider mite damage on any plant.
Spider mites look like a dust on the back of rose leaves - notice the white dust built up along the spine of the leaf in the photo below. Close observation will show movement.