Shrub Problems

1. Q. What insects eat shrubs until the plants finally die? Maybe my problem is a plant disease! Anyway, the plants die!

A. Pests are not the main killers of shrubs. In fact, insect and disease attack are not related to 80 percent of woody plant problems. Rather, four major areas of cultural and environmental problems account for a lack-luster performance by woody plants in many landscapes.

  1. Poor soil preparation and poorly executed planting techniques cause most plant loss.
  2. The use of plant material generally not suited to the site or the general region is more common than would be expected.
  3. Poor maintenance and lack of knowledge of necessary cultural practices once the plant is on the site kills many plants that manage to get planted correctly.
  4. Construction damage, alteration of the native environment and equipment damage kill many plants.

2. Q: All summer my photinias and roses have taken on a terrible look. The leaves are curled, crinkled, and misshapened. What can I do to help them now and to prevent it in the Spring and, what is wrong with them?

A: Photinias and roses are sort of related plants and neither enjoyed the hottest, driest summer in history. Both do better in a milder environment and when extremes are experienced, both suffer. They were just trying to stay alive! The roses should be fertilized with Winterizer fertilizer (15-5-10) in October then pruned and refertilized next February. The photinias are a different story. If the photinias had green foliage and grew normally, they will recover and do well next year. However, if photinias were yellow with black spots on the leaves, the plants are in an highly alkaline planting area and will NEVER get better -- only worse. Plants in such an area should be removed and replaced with an adapted shrub such as Standard Yaupon or burford holly if screening is desired. Photinias in good condition (and they may be just feet from a sickly plant) can be left and will perform well. Once a photinia begins to show signs of "a bad location", no amounts of iron supplement or fungicide spray will solve the problem. If roses are old and extremely damaged, you may want to choose another variety and get another plant next spring.

3. Q: My pigmy palms have brown, shriveled branches due to cold and wind burn...should I trim back completely or leave them alone. Also my hybiscus trees have also lost all leaves...should I trim or not?

A: Wait several weeks until all of the freeze damage on effected plants can be accessed then cut back to live wood. This is true for hibiscus and pigmy palms. Cutting back to green wood with live buds (hibiscus) and removing wind-damaged foliage should be considered grooming or "spring cleaning" so you will enjoy a more attractive plant this spring and summer.

4. Q: We have several large, mature Sago Palms. Each plant has several "baby" palms at the base which we must prune back yearly to maintain overall plant appearance & shape. We would love to be able to extract or dig out these young plants for transplanting, but I'm told this is very risky as both the parent and young plant will typically die. Any comments?

A: This is not risky at all IF YOU DO IT RIGHT. First, pile some soil around where the palm "pup" is emerging so the top of the pup is still exposed but more of the area where is is attached to the "mother" plant is covered. Some suggest scarring the surface at the point of attachment (pup to mother plant) before covering. The application of a rooting hormone such as Hormondin or Rootone to the scarred surface before covering can't help. Keep the area moist but not wet all the time. Within a year the pup should be able to be cut away from the mother plant and should have a well developed root system.

5. Q: How do I get my trumpet vines to bloom? Also, on occasion, some of the branches will rapidly turn brown and die back. If I don't prune the dead growth out I lose the growth all the way back to the main trunk. Do you know what may cause this?

A: If trumpet vines are grown in too much shade they will grow rapidly to "reach" for the sun and not bloom until they receive 8-10 hours of direct sunlight daily. The dying back has me stumped; I have seen it happen with plants receiving too much water and poor drainage (in containers) but it is rare. This is really the case for the Chinese Trumpet Creeper -- the Madam Galan is growing so fast the living covers the dead before you can detect it.

6. Q: Could you please tell me how to look after a yucca plant as the top leaves are ok. but the bottom leaves turn yellow and get very dry and fall off.

A: This is a natural leaf shedding. Simply remove the bottom leaves as they turn yellow-brown to keep your yucca with that well-kept appearance.

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