Diseases of the hedge: from fungal diseases to nutritional deficiencies, without forgetting harmful parasites and insects. Here's how to cure the different hedge diseases.
Boxwood, cherry laurel, laurel, fontina, pittosporo ... they are allhedge plantswidespread in Italy. They can toleratepruningeven heavy and repeated. They are suitable for more or less geometric motifs and are able to reach significant heights (5 - 6 meters, only the pittosporum hedge remains lower). These hedge plants, while quite resistant, are not immune to diseases.
Diseases of hedges
In the previous paragraph we have mentioned only some of the hedge plants widespread in Italy, in this paragraph we refer to the most common diseases that can attack the plants mentioned or other hedges. Let's start with the nutritional problems.
Hedge with yellow leaves
Iron deficiency, known as ferric chlorosis, is a very frequent problem for those who irrigate plants with calcareous water (hard water from the tap). The hedge plants at risk are the cherry laurel, laurel, pittospore and especially photinia.
This disease manifests itself with leaf yellowing and, in more extreme cases, the leaves turn white and dry out. When ferric chlorosis is left untreated, the plant completely stops flowering, ceases growth and undergoes rapid decay.
The remedy consists in compensating for the iron deficiency when the first appearyellow leaves of the hedge. Iron-based compounds are very common and are easily found in gardening shops, agricultural consortia or by taking advantage of online shopping.
The “chelated iron” fertilizers can be liquid or powder. Those granular or powdered must be buried quickly because the light tends to degrade this particular fertilizer. The chemical composition of these compounds makes iron available also in calcareous soils, i.e. those soils responsible for ferric chlorosis, the disease that causesyellowed leaves in the hedge.
To understand what iron-based fertilizers are, we invite you to visit the dedicated Amazon page:fertilizer based on chelated iron.
Iron chlorosis attacks younger leaves. When theyellowingconcerns the older leaves, probably it is nitrogen deficiency. With nitrogen deficiency, the plant slows down its growth and immediately appears suffering. Nitrogen deficiency mainly concerns pittospore, photinia, cherry laurel and can also affect boxwood and laurel.
Hedge attacked by fumaggine
Therefumagginedoes not spare any hedge plants. Among those mentioned the most exposed are the laurel and pittospore hedges, but as stated this mushroom does not spare any plant.
If thehedgehas leaves covered with a black and powdery patina, then there are no doubts, it is affected by smokiness.
To intervene, eliminate the insects at the origin of this disease and intervene by washing the affected leaves individually. Use water and Marseille soap. In case of extensive infection, treat with copper-based products.
Spots on the leaves of the hedge
There are fungi that cause spots of various shapes that almost look like burns. These spots can be punctate, irregular, rounded, elongated ... they have a color that varies according to the hedge plant. They appear brown and red or brown and yellow. Also in this case the treatment to be performed is based on copper.
Pest insect of the hedge
Let's start with the ozirrinco that erodes the edge of the leaves. This pest is an 8-10mm long beetle that causes severe damage. Biological control with entomoparasitic nematodes is recommended for this parasite, to be added starting from February-March.
Among the other parasites of the hedge there is no shortage of lice and scale insects. For remedies for hedge aphids (or plant lice), please refer to the page:plant lice.
Hedge with dry leaves
If yourshedgeshows, in spots, some completely dried leaves and twigs, it could be the insectXylosandrus compactus. It is only 2-3 mm long and at the moment the only way to slow down the infestation is to promptly eliminate (with burning) the dead branches. The damage is made more serious by some fungi carried by the insect itself.