Host an Event Volunteer Join Tickets

Support the plant database you love!

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?

Share

Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
Not Yet Rated

Wednesday - November 14, 2007

From: Glendale, AZ
Region: Southwest
Topic: Diseases and Disorders
Title: Navel orange disease problems
Answered by: Barbara Medford

QUESTION:

I live in Glendale, Arizona. I hav a mature miniature navel orange tree. This year it has lost a considerable amount of leaves. Also the fruit all has a large yellow spot. It looks pitiful. What should I do?

ANSWER:

We found an excellent site on dealing with problems with the navel orange trees. We really tried to find one from Arizona but couldn't, so you'll have to accept this Texas Cooperative Extension site, instead. Then, if you're really dedicated to find a solution, go to this site, "Diagnosing common citrus problems", and see what you can find that fits your situation.

As in a great many plant problems, especially, it would seem, with trees, plant stress gets a lot of the blame. One reference said that orange trees should be fertilized 6 times a year, starting in early March through August/September. Maybe your tree is just hungry. Or, if the trunk is not above the surface of the surrounding garden, or there is mulch spread over the root zone, the tree may be developing root rot or foot rot. Charming terminology. It look to us like the experts were pretty nonchalant about most of the problems with navel oranges, with comments like "not worth treating", etc. It's up to you to plow through that chart on citrus problems and see if it's worth it to you.

 

More Diseases and Disorders Questions

Possible disease on Eastern Redbud
October 06, 2007 - Our Eastern Redbud appears to be suffering from our recent drought. The leaves are turning brown in July/August on a few branches. A few black spots appear on the leaves before they turn brown. Ot...
view the full question and answer

Time to trim oak trees in Austin
October 29, 2011 - We have several large oak trees in desperate need of a good trimming. Given that the trees have had a very stressful drought year, when would be the best time to trim them?
view the full question and answer

Mountain laurel (Sophora secundiflora) refuses to bloom
March 07, 2008 - We have a Texas Mountain Laurel that gets full sunlight, but does not bloom. It is 4-5 ft tall & 3-4 ft wide & healthy. Is there anything we can do to make it bloom next year?
view the full question and answer

Central branches on Texas Ash have died
June 09, 2015 - I have a Texas Ash tree that was planted about 4 years ago. It seemed fine last summer and was well watered. This spring, when it started leafing out, the central branches at the upper part of the tre...
view the full question and answer

New nursery plants with sappy spots from Round Rock, TX
September 09, 2012 - We live on the west side of RR, near Cedar Park and recently bought three 15 gallon cherry laurels from a nursery. Started to plant them today as we bought them a week ago and noticed base of the trun...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.