Gardening : Work in Raised Beds to Control Soil Content

QUESTION: My son lives in Redlands, where the soil is clay that stains the stucco. There is also hard pan, which inhibits good drainage. Do you have any suggestions for preparing the soil so he can plant a garden?

ANSWER: If the soil is as bad as you describe it, only the addition of huge amounts of organic materials would improve it. This would involve countless hours of backbreaking labor over a long period.

I suggest that your son garden in raised beds, where soil conditions can be controlled by the use of a commercial soil mix or one that he makes himself. Raised beds are not only a practical solution to poor soil; if done properly, raised beds can be an attractive addition, or even the focal point of a landscape.

In addition, cultivation is greatly reduced, irrigation and weeding are easier, and it’s generally easier on the body, as the necessity for kneeling and stooping is lessened.

Preventing Aphids Requires Vigilance

Q: I have three orange trees planted in my front lawn, each about three years old. The leaves are curly and distorted, and a few fruit, which are still green, have split open. I treated the trees for aphids last spring by applying soapy water. Please let me know your thoughts on this.

A: The curly, distorted leaves are indeed caused by aphids and the soapy water was a good treatment. The problem is that you didn’t treat the trees often enough. Aphids occur in cycles and require treatment every time they recur.

Examine the foliage on a periodic basis and treat with the soapy water each time you observe an infestation. As to what causes the oranges to split open, it is probably either due to an abrupt climatic change or improper irrigation.

--B.S.

Salt Buildup Can Turn Avocado Leaves Brown

Q: What is causing the leaves on my Fuerte avocado tree to turn brown on the sides and tips?

A: This foliage burn is probably the result of salt buildup in the soil. In normal rainfall years, this usually isn’t a problem because the rainfall flushes the salts from the soil.

However, due to our drought, salt buildup has become a problem. In the absence of heavy rainfall, it would benefit your tree to give it a very deep soaking every six months. Let the hose run slowly for several hours. Apply the water away from the trunk in a wide band that encompasses and even extends out farther than the drip line. As avocado roots are fairly shallow, this will help leach the salts from the upper portion of the soil and should help alleviate the problem.

--B.S.

Ladybugs Can Control Other Bugs on Orange

Q: Most of the leaves on my navel orange tree are white with fuzzy bugs. The oranges deform, rot and fall off the tree before they are completely ripe. What is the remedy for this?

A: The fuzzy white bugs are cottony cushion scale. They affect the foliage and often cause an infection which enters the orange from its navel end. Cottony cushion scale is usually controlled naturally by ladybugs.

To encourage ladybugs and other predatory insects, it is a good practice to hose off the foliage of the tree periodically. Dust and debris that accumulate on the leaves interfere with beneficial insects. If this doesn’t work, consult a nursery about chemical control.

--B.S.

Bougainvillea Plentiful but Handle With Care

Q: Can you give me advice and sources where I can purchase bougainvillea plants in containers?

A: Almost all Southland nurseries and garden centers sell potted bougainvillea plants in containers. As far as advice is concerned, be very careful when you remove a bougainvillea plant from its container. The roots are easily disturbed. It is best to cut the container away from the root ball rather than pull the plant out of its container. San Diego Red is a good all-around bougainvillea variety.

--B.S. Questions should be sent to Garden Q&A; in care of the Real Estate Section, Los Angeles Times, Times Mirror Square, Los Angeles, Calif. 90053. Questions cannot be answered individually.