Slugs can cause a lot of damage in the garden, especially when the infestation is rampant. Luckily, slugs are fairly easy to deal with in a variety of ways. If you share a garden with slugs, you have to take drastic measures.

Slugs can destroy entire crops if left unchecked

Table of Contents

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  1. the essentials in brief
  2. Fight slugs
  3. crop protection
  4. Nudibranchs - Species
  5. Nudibranchs - Reproduction
  6. food and predators
  7. prevention
  8. frequently asked Questions

    9. the essentials in brief

    • Bait provided in traps will attract slugs. Beer, dog and cat food and wheat bran are suitable as lures. Some plants keep slugs out of the vegetable patch, while fences and barriers block crawlways.
    • If home remedies are used in the garden, the Plant Protection Act should be taken into account. Certain foods, such as coffee or salt, are not suitable for killing slugs. Preventive measures should be preferred to control.
    • There are numerous slugs, of which five species are considered important crop pests. Some representatives turn out to be useful. Their reproduction is a natural spectacle lasting several hours.
    • Nudibranchs are omnivores that prey on carrion and plants. Their slime deters numerous predators. Hedgehogs, birds and mice as well as some insects are among the natural predators of snails.

    How do I fight slugs?

    When slugs become a nuisance, this indicates an imbalance in the garden. The dreaded visitors multiply in large numbers when natural enemies are absent and living conditions are optimal for them. There is a whole range of remedies against slugs, but there is no 100% guarantee that slugs will be driven away permanently. If you want to get rid of slugs, you need to make your yard slug-unfriendly.

    Nudibranchs feel at home here:

    • mulched beds with even moisture
    • shaded areas where temperature fluctuations do not occur
    • Microhabitats with warm, humid weather such as compost

    Defense by bait and trap

    Nudibranchs can be baited and collected

    There are ways you can keep the mollusks away from valuable crops. A mix of moistened dry dog or cat food and wheat bran is a treat for slugs. Offer the bait in recycled cups that you bury in the ground. You can then easily collect and dispose of the snails.

    How to build a beer trap:

    1. Cut square corners at the top edge of a yoghurt pot 2 cm apart
    2. Fill the mug with beer to an inch below the cutouts
    3. Close with lid to avoid watering down from rain
    4. Dig the cup into the ground so that the rim sticks out an inch or two

    Remove and empty the container regularly to keep the trap effective. To keep the first generation of slugs of the year at bay, bury the beer trap in your beds between November and April. Multiple containers also increase success.

    Plants against slugs

    Instead of your vegetables and salad plants, sacrifice herbs that magically attract the reptiles. This includes the student flower. It has special glands on the leaf edges and roots, which secrete a scent. This is particularly attractive to slugs, which is why tagetes species are well suited as border plants for vegetable beds.

    Use plant extracts:

    • Mix fern or liverwort extract with water
    • spray on crops
    • Repeat this measure after a downpour

    Plant extracts act as a deterrent to slugs and are harmless to plants because they do not penetrate tissue. However, the mollusks develop different preferences, so you should try different plants and extracts for spraying. Savory and chamomile are also considered to be effective means of repelling snails.

    obstacles

    Snail fences keep voracious invaders away

    Snail fences serve as an insurmountable obstacle for slugs. Alternatively, spread a wide layer of lime and sawdust around the beds. This belt is avoided by most snails because the mollusks do not crawl over rough surfaces because of the risk of injury. Lime also etches the sole. The disadvantage of this method lies in the short-term effect. Rain renders the barrier ineffective, which is why you should spread the substances regularly.

    digression

    Do Roman snails help against slugs?

    Many hobby gardeners answer the question "What to do against slugs?" by using Roman snails. They are among the largest native snails and are protected. Their main diet includes withered plant parts and algae growth.

    Cannibalism can sometimes be observed in young snails in the breeding cavity. They eat other young snails and don't stop at clutches. Cannibalism no longer occurs in adult animals. It is a common myth that Roman snails feed on other snail eggs.

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    Caution: Observe the plant protection law

    Not all home remedies are permitted for use in private gardens. Many hobby gardeners classify substances from the kitchen as harmless, but numerous products are poison for nature and its creatures. Therefore, the Plant Protection Act prohibits the use of self-made products that are not officially approved as plant protection products and can damage organisms.

    Coffee kills beneficial insects

    The effect of coffee on slugs has now been proven. Used in low concentrations, coffee grounds act as a deterrent. Higher doses will kill the mollusks after they eat the crumbs. The reason for this effect lies in the caffeine, which acts as a neurotoxin. However, there is a risk that beneficial insects will also be affected. According to the Federal Environment Agency, it is not permitted to use self-made coffee brew as a snail control agent.

    Salt changes the habitat

    Table salt removes moisture from the snail, so that it slowly dries out and dies. However, salt can also damage plant roots if it accumulates in the soil. If deposits form, salt-loving plants settle in the garden and the actual useful plants have no chance of surviving. Burns may occur on the leaves of treated plants. Therefore, salt is considered a poison for the garden.

    Which slugs live in the garden?

    The black slug is mostly jet black

    Slugs are species that have almost completely reduced their shell in the course of their evolution. The remains of a shell have been preserved in the soft body of some representatives. This makes it impossible for the slugs to move into a protective housing. The group is very species-rich and not uniform, because the process of shell reduction took place within different snail families.

    The Spanish slug is one of the most common snail species found in Germany. Up to 12 individuals live on one square meter of cultivated land.

    crop pests

    There are a few representative species that can be considered crop pests. The inconspicuous gray snails, which are just under a centimeter long, are among the most voracious herbivores along with the red and Spanish slugs. However, the latter is less picky when it comes to food. Because of its high tolerance to drought and sun, the species has good chances of survival. These continue to rise as the Spanish slug is spurned by snail hunters because of its bitter slime. But other species can also be dangerous to crops.

    Latin name size coloring abnormalities
    Black slug Arion ater 10-15cm jet black, rarely gray or dark brown dark sole
    Reticulated field slug Deroceras reticulatum 4-6 cm brown to grey reticulated spots
    garden slug Arion hortensis up to 50 mm dark brown to black with a reddish tinge Sole of foot yellowish
    Red slug Arion rufus 12-15cm black, brown, red or orange elongated wrinkle
    Spanish slug Arion vulgaris 7-15cm black, brown, red, orange, yellow Juveniles yellowish with a dark longitudinal band

    beneficials

    Even if feeding damage caused by slugs causes displeasure among many garden owners, these molluscs perform important tasks in nature and are therefore also useful. They are considered the health police because they recycle decomposing plant remains and devour dead animals. In this way they keep the garden and beds clean and promote the formation of humus. Because of their diet, slugs are more commonly seen on compost where they accelerate the decomposition of organic matter.

    These species are useful:

    • Tiger slugs: Snails with a tabby pattern and a prominent keel
    • Worm Slug: worm-like snails that eat slug eggs
    • blue slug: conspicuous species that eats mainly mushrooms and lichens but also strawberries
    • shiner: welcome guests who eat nudibranch eggs

    How do slugs reproduce?

    Slug mating is a slimy affair

    Watching slugs mating is a natural spectacle. The molluscs are hermaphroditic and have their sex and accessory organs in a common genital apparatus. All individuals can mate with each other. The mates find each other by following a trail of slime. Before reproduction occurs, an elaborate mating dance takes place. The following reproductive mechanisms relate to the Spanish slug.

    background

    Where do slugs come from?

    About 90 percent of all garden damage caused by snails comes from the Spanish slug. Little is known about their original origins, so the spread in Europe can only be reconstructed in outline. The first evidence that the species has spread in Germany comes from the Rhine area and dates back to 1969. In 1980 the Spanish slug colonized large parts of southern Germany.

    partner finding

    The molluscs orbit each other in a clockwise direction, producing large amounts of slime. The mating dance can come to an abrupt end if the snails are in the wrong reproductive cycle or the animals are not genetically compatible. If the dance was successful, procreation occurs.

    propagation

    The animals entwine and press their bud-like reproductive organs together. They evert the epiphallus and spermathecae duct, which is usually not visible to the observer. A spermatophore formed in the epiphallus is pushed into the partner's spermatic duct by weakly pulsating movements. In this phase, the snails can remain almost motionless for several hours.

    separation

    After the snails have separated from each other, they resume their circular movements. They are still connected to each other by the spermatophores, which are anchored in the duct by recurved teeth. With a jerk, the individuals separate from each other, leaving the seed packets in the respective partner.

    development

    Because slugs are hermaphroditic, both sexual partners lay eggs

    After several days to a few weeks, both partners independently lay their eggs in several clutches. To do this, the snail looks for a moist and sheltered place on the surface of the earth, or it buries the eggs to a depth of ten centimeters in the earth. Egg laying takes place mainly from the end of June and reaches its peak between August and September. In mild years, this event can drag on into December.

    • up to 225 eggs per clutch
    • a snail produces between 200 and 500 eggs
    • at an ambient temperature of 20 degrees, the development takes 30 to 37 days

    Young animals hatch in the same year from the eggs laid in summer. If oviposition took place at a late point in time, the eggs survive the winter. The young slugs are about ten millimeters long and reach their full body length by late summer.

    What do slugs eat?

    Snails have a special organ that is unique in the animal kingdom. The so-called rasp tongue (also radula) is occupied by numerous teeth, which are adapted to the food. In herbivores and scavengers, the rasp teeth are uniformly structured so that the plant material can be gnawed away.

    tips

    Keep the soil in the bed as open as possible so that the surface can dry out. Snails do not feel comfortable in this environment.

    omnivore

    The slugs belong to the omnivores, which feed mainly on plant material, but also eat carrion. Tender young plants or useful plants with thick fleshy and juicy leaves are part of their favorite food. Ornamental plants are not spared either. They usually eat the leaves from the edge until only bare stalks remain. Pitting is also typical.

    • strong smelling herbs are spared
    • tender leaves of cabbage and lettuce are very popular
    • large-area foliage of hostas is not scorned

    What animals eat slugs?

    Slugs are a delicious meal for hedgehogs

    Slugs produce a viscous slime that is used for better locomotion and protection, but is also effective against natural enemies. Its bitter taste ensures that few predators attack slugs. Hedgehogs will eat slugs, although they prefer worms, fruit, and insects. Shrews, blackbirds, magpies and starlings are also among the snail-eaters, along with slowworms and toads. Chickens eat newly hatched slugs or eggs. The larger the snails get, the higher the risk of choking for chickens.

    These animals are useful egg eaters:

    • ground beetles and their lavas
    • centipede
    • Fireflies and their larvae

    Prevent the slug from spreading

    Well thought-out prevention is better than fighting it. Create a species-rich garden in which beneficial insects feel comfortable. With a few measures, you can make the environment snail-unfriendly, so that a massive spread is nipped in the bud.

    tillage

    Regular digging ensures that the soil is finely crumbly. If there are no cavities, young snails have nowhere to retreat and are defenseless at the mercy of their enemies. In the fall you should turn fallow and coarse beds with a cultivator. This brings egg clutches to the surface, where they freeze to death or are eaten by predators.

    tips

    A finely crumbly and dry soil does not offer ideal living conditions for snails. Amend heavy and loamy soils with sand or compost.

    Mulch with care

    Mulch (€239.00) only gives limited protection against slugs

    Remove old bark mulch from beds in spring and dry the material before composting. Egg clutches can be found in the mulch, which can also hatch on the compost. If you decide to apply a new layer of mulch, you should keep it as thin as possible. Snails do not feel comfortable in fresh and finely chopped coniferous bark.

    prefer plants

    Many slugs prefer to attack young plants whose soft leaves are particularly easy to eat. When the leaves have developed a harder tissue, they become uninteresting to many snails. Therefore protect young plants with snail collars or prefer the seeds in the greenhouse on the windowsill. A balanced fertilization is necessary so that the plants can develop a solid leaf tissue. Well cared for specimens survive snail damage better.

    Plant hardy vegetables

    Some plants protect themselves from snail damage with hair, essential oils or leathery leaves. These include marigolds and carnations as well as potatoes, tomatoes and leeks. Mediterranean herbs such as sage, rosemary and thyme are also rejected by snails.

    frequently asked Questions

    How old do slugs get?

    How long slugs live depends on their species, size and environmental factors. While the tiny dwarf snails hardly get older than a year, the Spanish slug has a life expectancy of about three years. Most snails die after laying their eggs. Only unfertilized and mature specimens overwinter.

    How do slugs hibernate?

    The hibernation stage of the Spanish slug is represented by the juveniles. The eggs hibernate more rarely, so that the juveniles hatch only in the following spring. These stadiums can withstand temperatures as low as minus two degrees. While the eggs are already protected in the ground, young snails dig into the substrate. The adult animals that survive the winter also hide in deeper soil layers.

    Are slugs poisonous?

    Slugs produce slime to protect themselves from predators. This contains bitter substances and thus ensures an unsightly taste experience. Some species produce toxins that are secreted with the mucus or lodged in the skin. One of these representatives is the ground neel. Slugs are usually harmless to humans.

    Where do nudibranchs live?

    Since the animals do not have a protective housing, they have to seek shelter in the environment. During the day, slugs prefer to crawl around under the protective plant cover, between piles of wood or on the compost. Only at night, when the heat has subsided, do the molluscs emerge from their hiding places.

    How are slugs formed?

    The mollusks are hermaphroditic and reproduce by mating with a mate. If two animals have found each other through the slime trail, there is a snail dance. The partners then press each other so that their sexual organs connect. They exchange packets of seeds through rhythmic movements before detaching and going their separate ways. Each animal lays eggs independently of one another, from which young animals hatch after a few weeks. Temperatures between ten and 25 degrees Celsius are necessary for successful development.

Category:

Animals in the garden