Question
QUESTION: Dr. Vann
Every year my day lillies come up healthy aand thriving. Then, the tips of the leaves begin to yellow. Over time - weeks - the yellow progresses down towards the baseand previously yellowed areas turn brown. This usually only progresses up to a few inches from the tip. Otherwise the plants appear healthy, going through a normal blooming. While the plants seem to handle this, since they are there for aesthetic reasons, they would look a good deal nicer without this terminal discoloration. What is the problem, and how can I prevent it?
Thanks.
DBRJ

ANSWER: Dave:
There may be a water or heat issue where you live. This does not sound like a bona fide infectious disease, but rather an environmental issue. Be sure they have a good supply of water and nutrients.  Be sure to look for a disease called rust. It produces small yellow or orange yellow raised "pimples" on the leaves. This can yellow up the leaves and make them brown too.

Steve

---------- FOLLOW-UP ----------

QUESTION: Steve
Thanks for getting back. Although we have certainly had the heat this year, since the problem occurs every year, that cannot be the sole answer. From your description, I would not think rust is responsible. However, water and nutrition raise a question. These plants seem like such rugged individualists, we do tend to let them fend for themselves. We'll look into more attention to watering and fertilizing next year and see what happens. Thanks for your input.
DBRJ

ANSWER: Dave:
You are right, these plants can take a lot of abuse and still keep ticking.  Growing daylilies here is a big hobby. I just finished testing some chemicals for rust on 'Pardon Me' cv.

Regards
Steve

---------- FOLLOW-UP ----------

QUESTION: Steve
On closer examination - how embarrassing - my wife points out that the plants I was currently concerned about were IRISes - NOT daylillies! On the other hand, a quick check around to the back yard showed that the (actual) daylillies there did indeed also show the same sort of discoloration. I had suspected a disease because our tomatoes also display a similar discoloration midseason, and I am pretty sure that that is blight. Again, dry brown area transitioning to a narrow reddish then yellow band transitioning to healthy tissue. Coincidence, I guess?
DBRJ

Answer
Dave:
Hey, it happens to the best of us- no problem.

Could you send along a closeup photo of a few of the daylily/iris leaves that are showing this discoloration?  Be sure to review your image on your computer first...to be sure it is in focus before sending.

Yellowing/browning of the foliage can mean many things- it is a generic symptom, many times it is related to the roots and/or soil.

Steve