Lilacs ( Syringaspp . ) are a group of about 20 flowering shrubs and trees , most of which are native to Asia . They are develop for their fragrant , showy blooms that come in shade of purple and pink as well as white .
Even when not in bloom , lilac trees and shrubs are still attractive plants . However , foliage diseases due to kingdom Fungi and bacteria are unwashed lilac problems that can affect the show of the plants .
Types of Lilac Trees
Lilac Sir Herbert Beerbohm Tree produce aslarge shrub or bushes . The uncouth lilac ( Syringa vulgaris , USDA plant hardiness zones 3 to 7 ) is a large bush with a height up to 12 feet . Some cultivars of the common lilac are more immune to diseases than others .
The Nipponese tree lilac ( Syringa reticulata , zone 3 to 7 ) , on the other hand , grow in true tree diagram form with a acme of up to 30 fundament . The jacket of this Sir Herbert Beerbohm Tree has a rounded , oval shape .
Diseases of Lilacs
Let ’s go over some of the most usual lilac diseases , their causes and how they can be managed .
Powdery Mildew
One of the most common fungal disease of lilac George Bush and tree ispowdery mildew , which manifest as a powdery white substance on lilac tree leave . This disease tend to occur in humid term , so providing good air circulation is fundamental to keeping plants teetotal .
This disease affects the show of the plant but does not cause meaning damage .
Tip
The Japanese tree lilac is more resistant to powdery mildew than the uncouth lilac .
Fungal Leaf Spot
Many lilac species , including the common lilac and the Nipponese tree lilac , are susceptible to foliage post because of the fungusPseudocercospora . Like powdery mildew , this lilac disease incline to rise in humid conditions and can do browning of the parting and extensive leaf drop .
Fungicides containing copper sulphate , triticonazole or tebuconazole can aid hold the spread of this lilac fungus .
Bacterial Blight of Lilac
Leaf spots on lilac tree leaves can also be stimulate by the bacteriumPseudomonas syringaepv.syringae . The disease begins as brownish spots on leave-taking that result in foliage drop and eventually move to the stem , do wilt disease .
The bactericide copper octanoate can facilitate control this disease . However , it is important to note that without a science laboratory test , it is often hard to separate bacterial leaf topographic point and fungal foliage spots on lilacs .
Leaf Scorch
When the dirt in which lilac are grow becomes so waterlogged during rainy menstruation that some of the beginning die , it can result in a condition known as leaf singe . The leaf of the plant dry out but stay committed to the flora .
Lilac Tree Care
Lilacs that are stress , meaning they are not receiving enough water or nutrients , are more vulnerable to disease . Therefore , effectual cultural practices can help keep the flora healthy .
Lilacs produce best in full sun in moderately moist , well - drain stain . Established lilac shrub should be fertilized every few long time with a plant food formulate for bush . Avoid fertilizers rich in atomic number 7 , which can advance foliage production at the disbursement of efflorescence .
The pathogen that causePseudocercosporaleaf smirch and other foliage spot diseases on lilac bush and trees are known to winter on fall leaves and other plant debris . Therefore , raking up and discarding all the debris around your lilac Sir Herbert Beerbohm Tree at the destruction of the mature season can help to control the bed cover of these diseases .
