Spider mite

Spider mite, also known as spider mite, is a collective name for various types of mites that attack plants. These small insects belong to the family of Tetranychidae. The greenhouse spider mite ( Tetranychus urticae ) is most common in the Netherlands.

Spider mites are small, round creatures that look like spiders or ticks and are up to 0.5 mm in size. They can have different colours, such as brown, red and green. The mites like to hide on the underside of leaves.

The life cycle of the two-spotted spider mite ( Tetranychus urticae ) consists of four stages: egg, larva, nymph, and adult mite. The cycle begins when an adult female lays eggs on the underside of leaves. After a few days, the eggs hatch and the larvae emerge, which have only six legs. These larvae feed on plant juices and molt into nymphs after a few days. Nymphs have eight legs and go through two instars before becoming adults. The adult mites are also eight-legged and can reproduce rapidly, especially in hot and dry conditions. The entire life cycle can be completed in just one to two weeks, depending on temperature and humidity. This rapid reproductive ability makes the two-spotted spider mite a notorious pest.

Spider mites cause considerable damage to both houseplants and garden plants by sucking plant juices. This leads to yellow spots , wilting and eventually leaf loss. The mites also spin fine webs , which hinder photosynthesis and reduce the aesthetic value of plants. In heavy infestations, plants can die completely. These mites can reproduce and spread rapidly, especially in warm and dry conditions, such as in greenhouses and during summer periods in the garden.

Below you will find a step-by-step plan to combat spider mites naturally, without using poison. You can combat spider mites in this way outside and in houseplants.

Step 1: Isolate the plant
Separate the affected plant from your other plants to prevent the spider mites from spreading.

Step 2: Cut away affected leaves
Remove and destroy severely affected leaves to immediately reduce the spider mite population and prevent further spread.

Step 3: Spray with water
Spray the plant, especially the underside of the leaves, thoroughly with a strong jet of water. This will wash the spider mites off the plant. In addition, spider mites do not like high humidity.

Step 4: Deploy predatory mites
Introduce natural enemies such as Persi predatory mites that eat the spider mites. The hungry predatory mites can eat up to 5 adults, 20 young spider mites or 20 spider eggs per day.

Do you want to make sure that the spider mites do not return? Then also release Nicus predatory mites at the same time. These predatory mites will emerge from the breeding bags in a period of 6 weeks and protect the plant against a relapse of spider mites.

The predatory mites can be used well at the same time. They can also be bought together in a Combi Deal .

Step 5: Check regularly
Check your plants regularly for signs of spider mites and repeat the above steps if necessary to prevent re-infestation.

Here are some tips to prevent spider mites:

Inspect regularly
Check your plants regularly for signs of spider mites, such as small holes, discoloration or webs. Early detection can prevent a large infestation.

Optimal humidity
Spider mites thrive in dry conditions. Provide good humidity by spraying regularly or using a humidifier.

Healthy Plants
Keep your plants healthy by feeding and watering them well. Healthy plants are more resistant to pests. Find out what your specific plant needs for care.

Nicus predatory mites
Introduce natural enemies of spider mites, such as Nicus predatory mites , into your garden or greenhouse. These can help prevent a spider mite infestation.

Quarantine
Quarantine new plants before placing them with your other plants. This will help prevent you from unknowingly introducing spider mites.

Remove leaves
Keep the area around your plants clean. Remove dead leaves and other plant debris that can be a breeding ground for spider mites.

There are several ways to combat spider mites, each with their advantages and disadvantages. Below we explain different methods of combating them, with the exception of predatory mites:

Combating spider mites with vinegar
Vinegar is an easy and inexpensive option for combating spider mites. Vinegar can help change the pH of the leaves, which is unfavorable to spider mites. Vinegar can also be harmful to the plant itself, especially when used excessively. It can burn the leaves and stunt the plant’s growth. In addition, vinegar is not always effective for heavy infestations and may require multiple applications.

Combating spider mites with garlic
Garlic has natural insect repellent properties and can deter spider mites. It is a safe and non-toxic method that does not cause any damage to the plant. Garlic extracts can easily be made at home. However, the effectiveness of garlic against spider mites is less powerful than, for example, the use of natural enemies. It can also leave an unpleasant odor. Regular application is necessary to effectively combat the mites.

Combating spider mites with alcohol
Methylated spirits can kill spider mites quickly and effectively. It is a powerful solution that can provide immediate results. In addition, methylated spirits are relatively cheap and readily available. The disadvantage of methylated spirits is that they can be very harmful to plants, especially if used incorrectly. They can burn leaves and damage the plant. In addition, they are flammable and should be used with caution.

Chemical control of spider mites
Chemicals can be harmful to the environment and beneficial insects. They can also leave residues on plants and fruits. In addition, spider mites can develop resistance to chemical pesticides with repeated use. Therefore, we would not advise the use of chemicals.