En EspaŅol

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
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
 
rate this answer
1 rating

Friday - March 21, 2014

From: Las Vegas, NV
Region: Rocky Mountain
Topic: Diseases and Disorders, Soils, Vines
Title: Yellowing leaves on Carolina jessamine from Las Vegas NV
Answered by: Barbara Medford

QUESTION:

Carolina jessamine, has yellow leaves. 3 years old, grows on south wall, full sun. Same plant, in partial shade, has green leaves. Should I feed yellowish plant some nitrogen? If yes how much?

ANSWER:

The first thing we do, when asked questions about a specific plant and problems with it, is to determine where that plant is native and whether being planted in the wrong soils and climate might be the cause of the problem. Follow this plant link to our webpage on Gelsemium sempervirens (Carolina jessamine). By doing so and using the link under "Additional Resources" we found on the USDA Plant Profile Map that Carolina jessamine grows natively no nearer to Nevada than Texas, and far east Texas, at that. That means that Las Vegas NV, in Clark County at the southeast tip of Nevada, is well out of the native range for this plant.

However, if you have the plant and most of it has been growing well for 3 years, we next need to see if there is a problem in the location of the plants with the yellow leaves. On that same plant webpage, you will see these Growing Conditions:

"Growing Conditions

Water Use: Medium
Light Requirement: Sun , Part Shade
Soil Moisture: Moist
Soil pH: Acidic (pH<6.8) , Circumneutral (pH 6.8-7.2)
Cold Tolerant: yes
Heat Tolerant: yes
Soil Description: Moist, well-drained, humus-rich soil. pH adaptable. Sandy, Sandy Loam, Medium Loam, Clay Loam, Clay.
Conditions Comments: The best flowering occurs in full sun."

So, what does this tell us about the differing leaf colors? Well, not much. It does well in both sun (6 or more hours of sun a day) or part shade (2 to 6 hours of sun a day) and blooms better in full sun. But this concerns leaf colors, not blooms. Although it likes acidic soils, which you probably don't have, it is pH adaptable. That leaves us with the soils, which no doubt are the same soils in both parts of your garden. Look at the Soil Description above. What our radar is picking up is the phrase "Moist, well-drained..." A plant with yellowing leaves is usually suffering from chlorosis, caused by a problem preventing the roots from accessing necessary nutrients from the soil. We found a previous answer from Las Vegas that is very apropos to your problem, although it concerns a different plant. From that previous answer:

"Yellowish leaves could indicate chlorosis, or lack of iron being taken up by the plant from the soil. This is often caused  by poor drainage and/or dense clay soil, which causes water to stand on the roots. Again, this could  be a problem caused by planting, perhaps without any organic material added to hole, or damage to the tiny rootlets that take up water and trace elements, including iron, from the soil."

Now we feel the problem is narrowed down to that particular area, and it is up to you to do the rest of the detective work, as we don't make house calls. Check to see if the soil is too moist, or the plant is on a grade where excess water drains into the plant roots. If you have automatic watering, consider redirecting some of it, or simply cutting down on the water. You could try adding some iron supplement to the soil in that particular area, but not too much. Native plants in general don't much care for fertilizer. That plant's roots may simply be drowning, and adjustment in its environment is the best fix and the cheapest. And we don't recommend adding nitrogen. While nitrogen does encourage the production of more green leaves and is usually applied to grasses, the addition of nitrogen will just enourage more leaves to grow, probably still yellowing, and thus reduce the energy available for blooms.

 

 

More Vines Questions

Mystery vine in Marlboro NJ
August 05, 2010 - I have a patch in my backyard where we planted pumpkins last year but it does not look like pumpkin vines to me. The vine is smooth and the leaves are long and oval that come to a point. There are s...
view the full question and answer

Aggressive vine with purple flowers in South Carolina
September 12, 2014 - Found an aggressive climbing vine with purple flowers in out vegetable garden. This garden was cleaned and new dirt, mulch and manure was put in in the spring. It was raked out after the infusion of d...
view the full question and answer

Cottage-style landscaping for Chesapeake VA
August 02, 2012 - Dear Mr. Smarty Plant staff, I recently moved into a cottage style home that has a poured concrete/paver patio. I am trying to come up with ideas for plantings that would 1. give me a bit of privacy,...
view the full question and answer

Evergreen vine for Lake Jackson, Texas
March 06, 2009 - I have some lattice for privacy that I would like to cover with an evergreen vine or ivy. One is facing to the west, the other to the east. What would you suggest?
view the full question and answer

Evergreen flowering vine for wall in Tampa FL
May 06, 2010 - Mr. Smarty Plants, I live in Tampa Florida and am looking for a non toxic, evergreen, profusely flowering vine to cover a wall. It needs to be cold hardy to approx. 20F. Thanks for your help
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center