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Diseases of geraniums

Basic rules for healthy and strong geraniums

Geraniums are strong and generous plants, it is easy to take care of them but to keep them strong and luxuriant you must still follow simple but precise rules. First of all, it is necessary to place them in a suitable place, making sure that they receive abundant light and air, in fact it must be remembered that they are native to southern Africa. They prefer cool and moderate temperatures around 15 ° C therefore in winter they can stay outdoors only in mild climate areas while in summer they adapt well to the heat and resist even short periods of drought, they do not tolerate the humidity that risks make them rot. Watering must be regular and abundant from spring onwards, but not excessive. They should be fertilized regularly, or in any case in the presence of signs of nutritional deficiencies such as redness of the edges of the leaves or stunted growth and scarce blooms, in this case it would be advisable to administer nitrogen and phosphorus. If well cared for, your geraniums will stay healthy.

Unfortunately, geraniums are often victims of annoying parasitic insects such as mites, aphids and whiteflies, which suck their sap and leave a viscous secretion on the leaves, which in turn is dangerous because it attracts other pests. To eradicate them, use specific products at the first appearance that also eliminate the larvae. Among the aphids we remember the Myzus persicae, small and green in color, which attacks and deforms the young plants, the vegetative apexes and the floral buttons. Among the mites, Tetranychus urticae or red spider mite is particularly widespread, which causes yellowing on the upper page of the leaves which take on a bronzed appearance, then dry up and fall. It is possible to identify small orange-yellow insects on the underside of the leaves with two dark spots on the sides of the body. The white fly,

Diseases of geraniums caused by plant parasites

Diseases of geraniums of fungal origin are often caused or at least favored by an environment that is too humid and stagnant water, therefore they can be prevented by using simple precautions such as using a well-drained soil, avoiding evening or excessive wetting. Once the disease occurs it is necessary to eliminate the affected parts, reduce watering and fertilization and intervene on the plant with specific products. If we observe on the upper page of the leaves some yellow spots and in correspondence on the lower one pustules of 5-8 mm that produce a brown-red powder we are in the presence of rust. Another fungus that attacks geraniums, usually in early spring, is Botrytis cinerea or gray mold, which covers the flowers and leaves from the edge towards the inside and slowly makes them rot. If action is taken promptly, the plant can be saved. If it is Pythium that attacks, necrosis and bright black rot occurs in particular at the roots, usually young seedlings are affected.

Diseases of geraniums: The most feared disease: the relentless bacteriosis of geranium

Among the diseases of geraniums, the most feared is bacteriosis against which unfortunately there is little to be done, is caused by the bacterium Xanthomonas campestris pv pelargonii. The main symptom is a browning of the triangle-shaped leaves with the tip facing inwards, which first makes them almost dry out and then inexorably fall; the umbrella folding is also characteristic, especially on older leaves. In the area near the collar, the stem has a dark area. Often the disease is caused by poorly performed pruning or the use of dirty tools that are not properly sterilized. First of all, it is necessary to remove the infected plant from the others to prevent contagion and replace the soil before inserting new plants; it can help to administer copper-based products,