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Growing gladioli is a fun and rewarding activity. A wide variety of varieties attract flower growers. Beautiful inflorescences of different shapes and colors can transform the site. But some gardeners, instead of luxurious plants, see small inflorescences, twisted stems in a flower bed. The main reason lies in the fact that inexperienced lovers pay attention only to the care of flowers. And often overlooked is another important stage in the cultivation of a flower – the prevention and treatment of diseases or pest control.
What diseases are found on gladioli
The main diseases of gladioli that occur on plants are divided into infectious and non-infectious. Often, infection occurs by seed or through the soil. Some pathogens are carried by pests that attack gladioli. As a result of damage, gladiolus cease to bloom, severe damage leads to the death of plants. Therefore, the planted flowers are regularly inspected in order to take the necessary measures in time, and carry out preventive measures. It is necessary to know the signs of diseases and varieties of pests that reduce the vitality of gladioli.
Gladioli are prone to diseases that affect all bulbous crops. But if these diseases are less dangerous for onions, then gladioli endure them harder. This is due to the constant work of breeders to improve cultivars. Many modern species cannot be grown without the constant use of special tools. Most of the pathogenic microorganisms that cause diseases live in the soil. Therefore, it is quite difficult to fight them.
The causative agents of diseases can be divided into groups:
- Viruses. Viral diseases spread in any regions and cannot be completely cured.
- Mushrooms. Fungal infections often affect gladiolus plantings on acidic soils.
- Bacteria.
Plants are infected by spores or through the root system. Some gladiolus diseases develop on weeds, which are often the main vectors. In addition, the causes of gladiolus diseases can easily be:
- unfavorable climatic conditions;
- non-compliance with the requirements of agricultural technology;
- poor variety selection.
Before you start growing and breeding gladioli, stock up on useful information about possible problems. The article will list the main pests, as well as gladiolus diseases and their treatment, photos of each problem.
Fungal diseases
Fungal diseases of gladioli are also called rot.
Among them, the most dangerous and most common is considered fusarium or dry rot.
This disease is caused by the fungus Fusarium oxysporum f.Gladioli. Among modern varieties, gladioli resistant to this insidious disease have not yet been bred.
The causes of the disease are:
- a combination of waterlogging of the soil and humid warm weather;
- excess nitrogen in the diet;
- planting gladioli on damp heavy soils;
- strong plant growth.
How to determine the defeat of Fusarium?
Outwardly, the disease is manifested first by the curvature and thinning of the leaves, and then by their yellowing and drying. If you look at the corm, then red-brown depressed spots are visible on it – signs of the disease.
The danger of Fusarium lies in its ubiquitous distribution. If corms are weakly affected by the disease, then this will not save neighboring healthy plants from infection. It is especially important to inspect the material before storing to protect the rest of the gladioli. At the first sign of fusarium, diseased corms are removed. If the disease is seen in plantings, then they are dug up simultaneously with the soil around the plant. You can prevent a fungal infection by:
- disinfection of corms in a solution of “Fundazol”;
- dusting the planting material with the same preparation before planting;
- alternating 15-minute heating (55 ° C) and cooling in cold water.
If infection could not be avoided, then the soil must be treated with thiazon with sand (1: 1). The mixture is applied during autumn or spring digging of the soil.
The following disease of gladioli, known to many gardeners – sclerotinia or black dry rot.
Like the previous fungal infection, it has the same reasons for its rapid development. But on acidic and damp soils, wet cold weather stimulates the spread of the disease. A sign of damage will be the appearance of small dark spots on the leaves. The leaves become weakened at the base, turn yellow, then dry out. There are no pronounced signs of the disease on the corm, but the disease manifests itself during storage. Spots of a yellowish tint appear, which, when enlarged, change color to red-brown, then black. The corm itself becomes hard and rots.
Early varieties of gladioli are more resistant to black dry rot disease. Preventive measures and ways to combat the disease are identical to those described above. If the soil is heavy on the site, then it will help:
- the introduction of coarse sand for planting gladioli;
- reduction of soil acidity and moisture by known methods;
- harvesting corms before the onset of bad weather.
Another serious disease that requires the attention of flower growers is gray rot or botrytis.
Caused by the fungus Botrytis gladiolorum. It can develop at any time in the life of gladioli and affects all the organs of the flower.
The leaves are covered with small brown spots with a red border. They grow, changing the color of the leaves, which die off. In wet weather, a fluffy coating is noticeable on the leaves. The stem breaks, then lodges, and the rot penetrates below. The corm dies. The spores of the fungus are carried by water and wind. Control measures do not differ from other fungal diseases, but you can add corm treatment with a solution of baking soda before planting (50 g of powder per bucket of water).
Less common diseases are penicillinous and hard rot, smut, curvularia.
Bacterial diseases
A great danger to gladioli is when grown on alkaline and neutral soils.
The most common disease is destroyed.
The tops of the leaves turn yellow, and spots of a red-brown hue form at the bottom of the plant. Subsequently, they are converted into stripes along the leaves. The leaves rot, the stem breaks at the base. Spots also form on the corm. First yellow, then brown. During storage, the spread of the disease is not observed. Before planting, the scab is cleaned off and the place of the cut is treated with brilliant green. Means of combating scab are ineffective. The best technique would be to select healthy material and carefully comply with the requirements of agricultural technology.
Cancer.
The main spreaders of the disease are nematodes and soil bacteria. An outgrowth forms on the bottom, premature germination of children may occur. With the disease, the peduncles become less durable, the flowers are small, the decorative effect of gladioli decreases. To cope with the disease, it is necessary to carefully sterilize the soil, destroy diseased gladioli and pre-plant the corms with Fundazol. The disease is not very common, but it is also dangerous for nearby cultivated plants.
Viral diseases of garden gladioli
Flowers can be affected by diseases:
- yellow bean mosaic;
- cucumber mosaic;
- jaundice asters;
- tobacco ring spot;
- ring spot of tomatoes.
The list speaks for itself, because these diseases are found on other plants.
A common problem is yellow mosaic virus.
An alternation of colored and uncolored areas appears on the flowers, which gives the inflorescences a variegation. The flowers themselves become small, and the inflorescences are elongated. Corms acquire tuberosity or, conversely, become flat, have a bluish tint. Transmission of the disease virus is possible at the time of cutting, by corms or their children.
mosaic cucumber also leads to the appearance of streaks throughout the plant.
From this disease, gladioli quickly wither, look oppressed with deformed peduncles.
When affected by mosaics, the spots may take the form of a closed ring, the leaves begin to twist. The bulbs are shrinking. Carriers of these diseases are pests of gladioli (aphids, thrips). To overcome the mosaic, it is necessary to fight parasites. Additionally, strict observance of agrotechnical requirements, the removal of all diseased plants, and the choice of healthy planting material are required. It will not be possible to achieve a complete victory over the disease with the help of chemical means, so the prevention of the disease will be the main weapon in the fight against the mosaic.
Jaundice asters
It can lead to the appearance of flowers of a green hue, thin seedlings resembling cereals, twisting of inflorescences.
List of the main pests of garden gladioli
TRIPS – pests not only of gladioli, but also of other plants.
Therefore, the fight against them must be waged throughout the area. This insect feeds on juice, which greatly weakens the plants, reduces their decorative effect.
The danger of thrips is increased by its ability to carry viral diseases. Severely affected flowers do not open, parasite larvae are inside the bud.
You need to fight the pest by spraying the plantings with insecticides and treating the bulbs. At least three sprays are carried out per season.
Wireworms.
So, they call the larva of click beetles. This pest eats the bulb from the inside.
If this defeat does not lead to the death of the gladiolus, then the danger of fungal diseases remains due to the resulting wounds on the tubers. This pest feels good on carrot, potato ridges, in places with a large distribution of wheatgrass. Therefore, planting gladioli after these crops is not worth it.
Onion root mite.
From this pest, in addition to gladioli, lilies, tulips, hyacinths suffer. Penetrate through the bottom of the bulb and lay eggs. The larvae feed on the juice of gladiolus corms, weaken the plant. To prevent defeat, you need:
- Observe crop rotation. Do not plant gladioli after other bulbs.
- Clean the material from old scales before storing.
- Carefully remove plant debris from the site.
- Be sure to conduct heat treatment and disinfection of tubers.
- Spray with preparations from onion mites.
General preventive measures to protect gladioli from diseases and pests
The focus is on disease prevention. After all, a diseased plant, sometimes, cannot be cured. And even beginner flower growers can prevent this problem. Therefore, simple recommendations for the prevention of diseases will be useful to everyone.
When growing gladioli, you must:
- Mandatory observance of crop rotation. Flowers tolerate one place well for no more than two years in a row. Then they begin to get sick more, and a year later a mass disease of flowers may begin. This is due to the multiplication of pathogenic microorganisms that cause diseases – rot and fusarium. Good helpers in soil disinfection are nasturtium, marigold, calendula and mustard. These plants are planted in the places where gladioli grew. Many flower growers place their plantings around gladioli, which brings the same effect and helps to avoid disease.
- Planting plants in ventilated areas. This helps to contain the rapid spread of fungal infections.
- Do not leave a diseased plant near healthy ones. It is necessary to remove, together with the corm, and part of the adjacent earthen coma.
- Carry out preventive spraying of healthy gladioli. For these purposes, use an infusion of garlic (it is prepared from 100 g of ground garlic and 10 liters of water) and a solution of potassium permanganate (5 g of the product is enough for a bucket of water). Potassium permanganate simultaneously with the disinfection of the soil, enriches it with potassium. This treatment is carried out in early September. Chemical compounds are used only in the initial stage of the gladiolus disease. They are not intended for treatment, but only for protecting healthy flowers growing nearby.
- Mulch planting gladioli with pine needles to prevent the occurrence of diseases. Sphagnum moss is also good for preventive purposes.
- Periodically spray gladioli from pests and diseases with preventive solutions of copper oxychloride and copper sulfate. Enough 20 g of the substance per bucket of water.
- After harvesting the corms for storage, remove all plant remains on the site to reduce the possibility of overwintering pathogens and pests.
These simple activities will allow you to save your favorite varieties for several years and protect them from diseases and pests.
