PLANTS : Sometimes Sorry-Looking Greenery Is Just Going Through a Phase

When a plant is ailing, don’t forget to ask: Is this normal for this time of year? Such less-than-obvious questions often point to the solution.

For example, most gardeners understand that leaf drop in the fall is common with deciduous plants. However, many evergreens also routinely replace some leaves at certain seasons.

Keep careful notes in checking the possibilities. The notes may help someone more expert pinpoint causes if you are unable.

Some things to consider:

Is the entire plant affected, or just one side? Did one side show symptoms first? When? Was the decline sudden or over a period of time? How does adjacent vegetation look? Are more insects than normal present?

Is just the one plant in trouble, or do similar ones show the same symptoms? Bark splitting? Leaves yellowing?

How long have you had the plant? Even with the best care and most favorable growing conditions, some are unlikely to survive more than a year or two.

Such answers may be all you need.

If not, consider what’s adjacent to the plant: an alley, a swimming pool, a driveway, a patio, the neighbor’s yard? Has something happened there recently?

Could new paving or a patio expansion have damaged extended roots on your plant or changed the drainage? Did the pool overflow? Chemicals spill?

Has a soil sterilant or vegetation-killing chemical been used under or around the plant within three or four years? Some persist in the soil for years but are not picked up by a plant until its roots grow into the area.

Did a neighbor apply sterilants in his yard, even if you didn’t?

Was the ailing plant put in too deeply or too shallow? Is there excess mulch?

Another possibility: excess fertilization.

A persistent, premature leaf drop suggests a check of watering practices. While a sprinkler system may produce a fine lawn it seldom supplies sufficient moisture for trees and many shrubs. Applying water more deeply may do it.

However, excess water can kill a plant as easily as extreme dryness. And wilting foliage can be an early symptom of either. Probing a few inches into the soil with a trowel, augur or long-blade screwdriver usually supplies the answer.

Also, it’s best to water in the morning so foliage dries before dark. In general, too moist conditions favor plant diseases.

Are underground animals a possibility? Gophers often eat succulent stems before their tunnels are noticed.

If some leaves look terrible but most leaves look OK, the plant probably is OK.

If only older leaves are affected, it could be lack of nitrogen or potassium, soil high in salts or poor soil aeration. A general yellowing of many leaves can be caused by lack of fertilizer, extreme sunlight or high temperatures. Yellowing of youngest leaves suggests lack of iron or chemical damage. Marginal burning usually is traced to salinity.

If the plant dies, be sure to examine the roots and the soil surrounding them. A bad odor often means the soil was kept too wet. Limited root development may indicate the same, or lack of water.