Posted by Newt on January 06, 2003 at 00:08:27:
In Reply to: Plumbago with yellowing leaves posted by Frustrated on January 05, 2003 at 01:17:03:
: My plumbago has yellow green leaves and doesn't look healthy. The soil mix is 1/3 mulch from the city, 1/3 sand and 1/3 garden soil (clay). I am suspecting that the city mulch may not have any nutrients. I have fertilized the plumbago with 15-10-15 as well as iron. So far, nothing works. What could be my problem?
The mulch would be a problem if it isn't well aged. If it's fresh and not well aged it will rob the plant of nitrogen. The best thing you can do for your soil is to add compost, even if it's pure clay. The mulch should also be used on top of the soil to hold in moisture and keep the soil temps more even.
I would suggest you dig around and take a look at the root system. Here's a site that might be helpful.
You might also want to have a soil test done. You can contact your local extension service.
Hope this helped,