· Gardenality.com's Answer
· Hi Kim,
There are a few possibilities as to what may be causing leaves to fall off.
First thing to do is to check for lacebugs. Lacebugs are a small insect that live on the underneath side of the leaves. Lace bugs are common flower garden insect pests that cause foliage damage and leaf drop throughout summer.They are 1/8 inch in length, grayish in color, and have a lacy looking shield. If this is your problem you won't have any trouble seeing them. They will be plentiful. Lacebugs usually go unnoticed due to the fact that they reside underneath the leaves.
If lacebugs are present you can spray with Neem Oil, Malathion, or Sevin to control them. I prefer using Neem Oil. Neem oil is 100% organic and very safe to use. You will want to repeat the spraying about 7-10 days apart, at least a few times to control the newly hatching larvae. Imidacloprid is a systemic insecticide that can be applied just prior to the growing season to control aphids for the entire season.
Over watering might be a possibility as well. Lantana are very drought tolerant and too much water will definitely cause them to suffer.
Over fertilization could as well be a problem. Fertilizer burn does result in yellowing and dropping of foliage.
Herbicides (weed killers) can also cause these symptoms. Make sure not to let the spray of herbicides drift over on to the foliage of desirable plants. Pelletized weed killers can cause damage. If the pellets fall on the soil above the root system of a plant, damage may occur.
Cold temperatures will cause the Lantana to have yellow leaves that turn brown and fall off. Temperatures around 40 degrees or below will cause this to occur. The Tangerine Lantana is winter hardy in Hardiness Zones 9A or warmer. In other words if the winter temperature ever gets below 25 degrees or so, the Tangerine Lantana will not survive.
Hope this helps you.