Mice and rats in compost: what to do?

The compost is an ideal habitat for rodents. Not only is there food in abundance here, the unwanted visitors also benefit from the protected and warming environment.

Secure compost

When setting up a compost rack, you should take appropriate precautions to prevent domestic rats, brown rats or mice from gaining access. Lay out a mesh mat on the surface. This should have a mesh size at which the macrofauna such as earthworms and beetles can crawl out of the earth into the compost substrate, but no rodents can get through. An ideal compost heap consists of a grate, wire mesh and lid. This ensures optimal ventilation and keeps unwanted residents away.

Tip: Build a lid yourself by covering a slatted frame with fine-meshed wire.

Prevent odor formation

Rodents are attracted by smells. If the compost smells intensely putrid or fragrances are released through fermentation, the animals quickly find the new source of food. Even when storing kitchen waste in collection bins, you should keep the formation of odors as low as possible. Regularly sprinkle some baking soda over the substrate, because this natural raising agent binds odorous substances. Empty the collecting bins on the compost heap at least every two days and pay attention to these measures:

• Spread vegetable waste and fruit over a large area
• loosen with branches of hedge trimmings, leaves or wood wool
• Cover waste with soil, plant material, or finished compost

Do not compost any leftover food

Mice and their relatives are more common when the composter is filled incorrectly. Substances that are difficult to break down, such as meat and sausage, as well as cheese or cooked leftover food, do not belong on the compost heap. Such waste is a popular food for rodents, which are omnivores.

Tip: You can compost leftover food in a worm box or in a Bokashi bucket before you put the decomposed substrate in the thermal composter.

Favor hot rots

The warm temperatures attract mice and Rats mainly in the cold season in the compost when it gets too cold in the area. Thermocomposters ensure even rotting even at low outside temperatures and generate heat, which rodents are happy to accept. Only in the event of intense temperature fluctuations or too hot and cold temperatures do the sub-tenants flee. To create uncomfortable conditions, you should work your compost regularly:

• shift frequently so that outer layers get inside and are heated
• Digging causes temperature fluctuations between the layers
• inside, temperatures rise above 40 degrees, so rodents are driven away
• pay attention to balanced moisture

Rodents often annoy

It becomes uncomfortable for the unwanted tenants when the compost heap is frequently disturbed. A well-managed compost not only improves the conversion rate, but also automatically keeps mice and rats away. If removing the lid every day is not enough, further disruptive measures are recommended:

• Implement completely at least twice a year
• prick the substrate more often with the digging fork in winter
• disturb noise-sensitive rats with noisy noises or restlessness

Avoid food sources

When the rats can no longer find any usable food on their compost heap, they look for alternative sources of food. Do not store yellow sacks outdoors, because leftover food in yoghurt pots will also attract the animals. Keep the garbage in inaccessible rooms until you pick it up and make sure that garbage cans are always properly closed. Birdhouses filled with various grains enrich the diet of rats and mice in winter. In areas with a high population density, you should refrain from winter feeding the birds. Also, check the area for possible attractions for mice and rats and talk to people about the problem:

• Overflowing garbage cans in apartment blocks or next to restaurants and canteens
• Feeding places for pigeons and ducks, where leftover bread accumulates
• rubbish bags stored openly at fairgrounds