misshapen lemons, caused by mites
If your oranges or lemons are cracked or split, take heart – you are not alone. The proliferation of this condition is not yet another Los Angeles disaster. It is something we can live with, and it happens wherever oranges or lemons are grown.
Russ Elliott of Van Nuys writes in about a 10-year-old navel orange tree whose fruit are splitting at the navel. Ralph Alaniz, of San Fernando, wants to know how to prevent lemons from splitting when they ripen, as they have done on his tree during the past two years.
Rose Bilski of North Hollywood, who has an otherwise flourishing garden, has a 1-year-old orange tree with split fruit and a young lemon tree with lots of fruit but no leaves. Her gardener waters each tree weekly.
Split citrus are most often symptomatic of irregular soil moisture. The scorching temperatures we had this summer, combined with a warm fall, have necessitated keen attention to watering over the last six months. Where such attention lapsed, split fruit could have developed. The heavy rains of last winter could also have resulted in splitting.
Typically, split citrus is the result of overwatering or of sudden heavy watering or rain after a long period of dryness. When citrus is overwatered, the inside of the orange or lemon will grow faster than the surrounding rind; the fruit doesn’t split so much as the pulp simply grows so fast that there is not enough rind to contain it. If water is withheld from citrus for too long, a soaking will cause the inside volume to suddenly expand, causing the rind to split. The split will begin at the point of least resistance which, in navel oranges, would be at the navel.
In general, citrus trees should be watered infrequently, but deeply. Garn Wallace, a soil and plant scientist in Torrance, recommends the following regime: Once a month, put a barely trickling hose under your tree and leave it for 48 hours. Citrus trees develop tap roots when irrigated in this manner and become accustomed to going without water for 30 days at a time.
By the way, those incredibly hot days we experienced this summer are not bad for citrus, as long as watering is properly done. Thousands of acres of lemons, for example, are planted in the Arizona desert.
The Ortho Problem Solver (Ortho Books, 1989) recommends watering when the soil is just barely moist in the top 6-12 inches. Build a berm, a circular hill of earth, several inches out from the trunk base, and build another berm around the drip line – the place where water drips off the tree during rain, beneath the canopy perimeter. In between these two berms is the area that will be filled with water once a month. The trunk is kept dry because of its sensitivity to waterlogging and soil fungus. Water should soak in as far as the drip line since this is where most actively growing tree roots are found.
Ortho states that fluctuating humidity and fertilizer levels may also bring about split fruit, and that thin-skinned citrus varieties are most susceptible to splitting. Tomatoes, by the way, split quite often, for the same reasons that citrus does.
Lemon trees, especially if they are small or living in containers, may defoliate this time of year. This condition is brought on by the cooler nights and shorter days of the autumn season. Defoliation should be followed by light pruning, fertilization, and a deep soaking.
Clara Drake of Woodland Hills sends a letter that contains drawings of a misshapen lemon, a lemon that looks like it was genetically engineered by a mad scientist. Such lemons are frequently encountered. They develop as the result of bud mites which, by sucking on lemons just as they begin to grow, cause disfigurement in the maturing fruit.
Aino Vimb of Sunland writes about his 70-foot-tall Australian silk oak (Grevillea robusta), which “looks like a sail” since the bottom 50 feet of trunk were stripped bare of all branches by a tree trimmer. He is “afraid it will blow over at some point.” I doubt this will happen since the wood of the silk oak is, in the words of botanist L.H. Bailey, “elastic and durable, valued particularly for staves of casks and furniture.”
Mr. Vimb mentions that some surface roots are visible, which might indicate weakness if this was a North American tree. However, since the silk tree is subtropical in origin, the appearance of such roots is not unusual. Trees native to tropical climes often have superficial roots, since the high humidity and rainfall do not require that water be mined from deep in the ground.
Tip of the week: One of the best flowers for the winter shade garden is cyclamen. This bulbous plant prefers soil that dries out completely between waterings. It is also grown as an indoor plant. Properly cared for, cyclamen should bloom until days get much longer in the spring. If not overwatered in the summer, it may live for several years.
