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The potworm is a larva of a mosquito. The Lyprauta spins a web of threads around itself that allows it to avoid the effects of many pest control agents. These threads are easily identified in the pot, making it obvious that there is an infestation. Eggs are deposited in cocoons in the pot.

Potworm mainly causes damage to the roots of a orchid plant. This damage provides an entrance for fungi and bacteria. After eating some of the roots, the root ends turn black and then rot away. The roots will eventually branch out, but this does cause growth retardation. In addition, potworm causes other damage such as fewer flower branches and failure to thrive.

The damaged roots cause;

• The (young) plant can absorb less nutrition;
• Soil salinization occurs in the pot;
• More energy goes into forming new roots; 
• The cultivation growth slows down;
• Reduced sales quality occurs;
• The plant is more susceptible to fungi.

Start with a clean substrate by steaming or freezing. Prevent infestation by covering the plant. This can be done by using fine mesh material that prevents the potworm from reaching the root tips. It is also important to increase plant resistance by applying Consecta. This increases the vitality of the crop and makes damaged root tips recover faster. The addition of AquaGro ensures that the water is better distributed through the substrate. This makes it more difficult for the eggs of the potworm to nest and flush out faster. 

With black sticky insect trap tape, you easily signal potworms causing them to be caught away.

Until now, no chemicals are approved for the treatment of potworm. Biological treatment is therefore the only option. Read more about this below.

Atheta counteracts the pest somewhat. Especially under the cloth used to cover the plants, the climate becomes more humid and better for this enemy. 

In addition, insects and parasitic nematodes can also be used to partially control the potworm. In practice, both Nemacontrol feltiaeand Nemacontrol heterorhabditis try to tackle the potworm. The first ten weeks are crucial to controlling the potworm, so it is recommended to release soil predatory mites immediately after potting. In addition, light traps help you monitor how many mosquitoes are present in the crop.

As mentioned earlier, the potworm thrives in a humid climate, and stagnant water in the pot or substrate is ideal for egg development. Some growers have tried steaming or freezing the substrate to start fresh. However, even after these methods, eggs can
still end up in the substrate. All of the above solutions are aimed at reducing the number of potworms, preventing their presence, or making their habitat less favorable.

Phalae Protect Gauze is a fine mesh material that covers the plant, making it more difficult for the gnats to lay their eggs. Initially, tests were conducted with hairnets. However, this material had the drawback of being inconsistently produced and did not allow water to pass through evenly. Following this, tests with Phalae Protect Gauze were carried out with customers.

The initial tests with the final Phalae Protect Gauze product yielded positive results. Fewer potworms were found, and the material allowed for good water and light permeability, creating a microclimate. Additionally, the cost of materials for the plants was reduced, and less labor was needed compared to the test with hairnets.

By using Phalae Protect Gauze, you need fewer biological control agents. You will achieve optimal results by covering both the top and bottom of the table.

Four pot plant growers took the test: Sion, Ter Laak Orchids, and Duijn-Hove. They all struggled with potworms in their plants and had already tested various pest control methods. The growers began cultivating in drier conditions to combat the potworms. This was also the case for grower Ron Moor from Sion. However, he noticed that dry cultivation hindered plant growth and that the root tips were still being eaten by the potworms, causing the plants significant stress.

After testing various materials, Phalae Protect Gauze emerged as the best option and was adopted by Sion, Ter Laak Orchids, and Duijn-Hove. All four growers experienced the same results:

The results after using Phalae Protect Gauze;

• Infection pressure from potworm midges is significantly less;
• The plant has better roots;
• There is less failure;
• The plant experiences much less stress because there is virtually no potworm pressure;
• Cultivation is no longer delayed by the plant's growth retardation normally created by the potworm;
• Plants on a table have become more uniform in terms of foliage;
• The mesh has good permeability to water;
• The plants are larger with a healthy green color;
• The mesh stops all (larger) flying insects, such as the Turkish moth.
• Light loss outweighs potworm control: Because the netting completely covers the plants, it affects light penetration. All growers revealed that this leads to about 10 15% light loss. Although this has no major impact in the summer, some growers continue to light longer in the winter. The light loss does not outweigh the potworm problem, however, this depends on the light level installed. 

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