A small red spider is causing major damage to fruit trees and grape vines in Germany. This refers to the fruit tree spider mite, whose greed for plant sap does not stop at ornamental and useful plants behind glass. This guide explains how to recognize the pest and distinguish it from other red spiders. You can find out effective home remedies for successful combating here.
How can you effectively fight red spiders?
The red spider, also known as the fruit tree spider mite, is a pest that sucks sap from fruit trees and vines. To combat them, effective home remedies such as water showers, potassium soap solutions, rapeseed oil solutions or plant decoctions can be used. In addition, beneficial insects such as predatory mites, lacewings, ladybirds and ants can contribute to the fight.
- The red spider (fruit tree spider mite) is 0.6 mm in size, has 8 red legs and a brick-red body with white bristles.
- Other red spiders in Germany are: red six-eyed spider, red glossy spider, the curly spider species Nigma flavescens and the canopy spider species Trematocephalus cristatus.
- As a pest, the red spider can be effectively combated with home remedies such as water showers, potassium soap, rapeseed oil and plant decoctions as well as the beneficial insects predatory mites, lacewings, ladybirds and ants.
Identifying and distinguishing red spiders
The fruit tree spider mite is called the red spider in Germany. In fact, it is not a real spider, but a tiny, red arachnid from the spider mite family (Tetranychidae). The following table provides an overview of the characteristics by which you can recognize the pest and distinguish it from other red spiders:
| Red Spider | Red Six-Eyed Spider | Red Glossy Spider | Curly Spider | Canopy Spider | |
|---|---|---|---|---|---|
| Size | 0, 5-0, 6mm | 7-15mm | 3-4, 5mm | 2-3mm | 2-2, 6mm |
| Color Body | red | red/white bottom | red | bright red | black-red |
| Color legs | red | red-brown | red to reddish brown | red-brown to yellow-brown | light brown to reddish brown |
| Special feature | Back with white bristles | 6 eyes | black eye hills | white dots abdomen | black abdomen |
| Botanical name | Panonychus ulmi | Dysdera erythrina | Hypsosinga sanguinea | Nigma flavescens | Trematocephalus cristatus |
| Middle name | Fruit tree spider mite | Isopod Hunter | Shining Spider | lurking spider | none |
| Family | Spider mites | Web spiders | Orb-web spiders | Curly Spiders | Orb-web spiders |
You can read more in-depth information about the appearance of the fruit tree spider mite and common red spiders in Germany in the following short portraits.
Red spider (Panonychus ulmi)
The fruit tree spider mite is hardly visible to the naked eye
A single fruit tree spider mite does not attract any attention despite its 8 legs and brick-red color. With a maximum size of 0.6 mm, the arachnid is tiny. The characteristic white bristles on the back can hardly be seen with the naked eye. Only with the help of a magnifying glass can you see that the red abdomen is pear-shaped. The piercing-sucking mouthpart for feeding remains hidden to an observer without a microscope.
Fatally, the Red Spider pursues a record-breaking family policy with up to seven generations per year. In combination with its preference for juices from fruit, vegetable and ornamental plants, these characteristics make the fruit tree spider mite a feared pest in Germany and Europe.
Red six-eyed spider (Dysdera erythrina)
The small red spider from the six-eyed spider genus is nocturnal and can rarely be admired live in action. Woodlice are their favorite food, which their second name refers to. For this reason, buildings and basements are their preferred habitat. The red six-eyed spider can be clearly identified by its white abdomen, which contrasts strikingly with the red forebody and reddish-brown legs.
Red spider (Hypsosinga sanguinea)
The red spider does not harm the plants - on the contrary, it also catches and eats plant pests
Dwarf shrubs and other low vegetation are the territory of the red spider. Here the little red spider busily weaves its orb webs in search of juicy flies, careless mosquitoes and similarly tasty prey. The red to reddish-brown body is decorated with light stripes on each side of the abdomen, which sometimes dissolve into light dots.
Curly spider (Nigma flavescens)
Curly spiders love variety. The color of the bodies ranges from bright red to reddish brown to light yellow. If you look closely, you can often see irregular, white markings on the abdomen. Some specimens boast a heart-shaped mark on the back.
Canopy spider (Trematocephalus cristatus)
It is the females of this species of spider that impress with their black and red color combination. The red forebody is complemented by black eye hills. The little spider beauty has delicate white hair on her black abdomen. The canopy spider spices up its light brown legs with delicate ringlets.
Excursus
Velvet mite – innocent doppelganger
The velvet mite (Trombidium holosericeum) is tiny, 2-4 mm long, has 8 legs and a red body. With these attributes, the widespread mite species looks very similar to the infamous red spider (fruit tree spider mite). In contrast to its harmful counterpart, the red velvet mite is a beneficial insect. At the top of the menu are the eggs and larvae of numerous pests, such as the dreaded phylloxera. The location provides an important clue as to whether you are looking at the velvety red beneficial insect or the brick red pest. Velvet mites love sunny walls, dry grass and forest edges. The red spider colonizes fruit trees and also accepts partially shaded niches.
Fighting red spiders biologically – remedies at a glance
Typical signs of a red spider infestation are twisted, small leaves and shoots as well as the fine webs of the mites
The infestation with red spiders can be recognized by the typical damage pattern. Light to brownish mottling spreads on young leaves, which is caused by fruit tree spider mites with their sucking and stinging mouthparts. Because the pests deprive a plant of its lifeblood, the result is stunted shoots and stunted leaves. Fruits remain tiny. The fruit peel corks up and spoils our appetite. It doesn't have to come to this if you regularly check your plants for red spiders from March/April. In an emergency, these biological control agents are available to you:
| Home remedies | Beneficial insects |
|---|---|
| Water shower | Predatory mites |
| Potassium soap solution | lacewings |
| Rapeseed oil solution | Ladybug |
| Plant decoction | Ants |
For visual inspections, be prepared with a magnifying glass. The sooner you get on the trail of red spiders, the more effective the recommended control agents will be. In the garden, especially check fruit trees, such as apples, pears, plums, gooseberries, currants as well as begonias, gardenias, primroses, hibiscus and all thick-leaf plants. In the greenhouse and winter garden you can take a look at cucumbers, tomatoes, orchids, cacti, palm trees and lemon trees.
The following video demonstrates in a practical and understandable way how to combat spider mites in the greenhouse on cucumbers using natural means:
Spinnmilben an Gurken - Erkennen und behandeln - Hausmittel und Nützlinge
Home remedies for red spiders – tips for combating them
The home remedies in the table above have proven to be excellent indoors and outdoors in the fight against cunning red spiders. The following instructions explain in detail how to use the natural remedies competently:
Water shower
- In the garden or in the greenhouse: spray infected plants vigorously with lukewarm water from the garden hose (tops and undersides of the leaves)
- Houseplants: put the root ball in a plastic bag, shower the plant upright and upside down
Sensitive orchids and other tropical houseplants resent a water shower. In this case, cover affected plants with a foil bag for 14 days. A noticeably high level of humidity arises in the immediate vicinity of the plant, which reliably destroys red spiders.
Potassium soap solution
- Heat 1 liter of water
- Stir in 15 ml liquid potassium soap (€19.00 on Amazon)
- add a few splashes of spirit
- spray affected plants every 3-4 days
Rapeseed oil solution
- Heat 1 liter of water
- Stir in 200-300 ml rapeseed oil
- Spray the tops and bottoms of the leaves
Plant decoction
Stinging nettle manure is a great fertilizer and also repels the red spider
- Throw 500 grams of nettle, wormwood, tansy or mugwort leaves into a vat
- pour 5 liters of rainwater over it
- Cover the tub with wire mesh and place it in a partially shaded location in the garden
- stir daily
- After 8 to 14 days, pour off the fermenting broth
Dilute the plant broth with rainwater in a ratio of 1:5 before repeatedly spraying plants infected with spider mites.
Tip
The red spider is not poisonous or dangerous to humans. With a body length of 0.6 mm, the red fruit tree spider mite is far too small to perforate human skin with its tiny mouthpart. Red spiders, which are only after plant sap, pose no danger to pets either.
Fighting beneficial insects Red spider
Ladybirds eat both aphids and red spiders
Predatory mites, lacewings and ladybirds enthusiastically hunt red spiders and eat their eggs and larvae with pleasure. The beneficial insects are available from special breeding farms, in online shops and in specialist retailers. Please ask carefully, because not every beneficial insect is suitable for combating fruit tree spider mites. The right predatory mite species against red spiders in the orchard is called Typhlodromus pyri. The predatory mite Amblyseius californicus is more effective in the greenhouse or winter garden. However, in the home on houseplants, predatory mites do not achieve any significant success against red spiders.
In the house, lacewings and ladybirds are the better choice against spider mites. The live beneficial insects in the larval stage are delivered in cardboard honeycombs or organic boxes, which you can easily position between the infected plants according to the breeder's enclosed instructions.
Have ants settled in your garden? Then hire the hard-working insects to help you against the red spider. Simply place infected potted, balcony and house plants close to the nest. In no time, ant workers have discovered the fruit tree spider mites as a food source and are making short work of the pests.
Frequently asked questions
How can you prevent spider mite infestation in the greenhouse?
Effective prevention against spider mites in the greenhouse is constantly increased humidity. We also recommend a regular supply of organic nutrients for strong leaf tissue that fruit tree spider mites and the like cannot penetrate. Ideally, adjustable shading prevents temperatures from rising to more than 30 degrees Celsius when exposed to sunlight.
We discovered a spider with a gray body and red stripes in the garden. What kind is this?
The variable crab spider has a light body with red stripes
According to your description, it is probably the variable crab spider (Misumena vatia). Males reach a maximum size of 4 mm, while females reach an impressive 10 mm in length (not counting legs). Female crab spiders can actively change their body color. A gray body with red stripes on the abdomen is very popular with spider ladies.
Is the bite of a red woodlouse spider poisonous?
Of the red spiders that are commonly found in Germany, an encounter with the small or large woodlouse hunter is rare. The six-eyed spiders with the characteristic white rump are out and about in the basement at night hunting for woodlice. If there is a confrontation with humans, the threatened spider defends itself with its powerful poisonous claws. The bite can be quite painful. However, the amount of poison administered is not dangerous for a human.
Tip
Red spiders love green tree discs. Hobby gardeners who are close to nature therefore avoid using grass and ground cover to plant under fruit trees. As a defense against fruit tree spider mites, it has proven to be a good practice to mulch tree slices with gravel, coconut slices or bark mulch.
