If you have a grub infestation in your private garden, you can use a number of control methods. For the sake of the environment and your health, chemical agents should only be used in extreme cases. Calcium cyanamide, which is officially approved as a fertilizer, is also not entirely uncritical.
Calcium cyanamide also harms beneficial organisms in the soil
Background on calcium cyanamide
Calcium cyanamide is the trade name of a fertilizer with roots dating back to before 1900. It is mainly used in agriculture, on the one hand as a nutrient supplement, but on the other hand also for weed and pest control. In the EU, however, calcium cyanamide is actually only permitted as a fertilizer. In specialist shops it is mainly offered under the brand name "Perlka" and consists of the following parts:
- Calcium cyanamide (almost 20%)
- nitrate
- Lime (about 55%)
The nitrate serves plants as a direct nutrient, as does the lime, which also has a pH-stabilizing effect and promotes soil permeability. The calcium cyanamide is broken down by water and microorganisms into slaked lime and toxic cyanamide - the latter is responsible for the herbicidal and pest-fighting effect.
problem of calcium cyanamide
Toxic not only for undesirables
The toxic cyanamide does not remain permanently in the soil. This is ensured by the microorganisms, which turn it into harmless urea, nitrate and ammonium. However, they need about 2 weeks until they are completely broken down - during this time not only pests and unwanted weeds are killed, but of course also all other germinating young plants and useful small animals. An application is therefore recommended at best in empty beds where you have found an underground grub infestation.
Correct dosage difficult
Applying calcium cyanamide to lawns can also be very effective. On the one hand, the grass benefits greatly from the fertilizing effect. On the other hand, the agent is particularly useful for preventing grubs, because May and June beetles prefer to lay their eggs on grassy areas due to the larvae's preference for grass roots. However, the correct dosage is not entirely trivial here. If it is not meticulously dosed professionally, over-fertilization burns will quickly occur.
Own health not at risk
Calcium cyanamide is also toxic to humans and therefore requires very careful handling. Be sure to follow the usage instructions carefully. Protective gloves must be worn and a face mask is also recommended. Because it is precisely the inhalation of calcium cyanamide dust that is dangerous. Finely powdered substrates are therefore no longer sold.