Water makes up more than 75% of the earthworm's body weight, so moist soils are preferred to prevent dehydration. Earthworms acclimate quickly by moving to humid sites or by entering a resting state.
Earthworms like moist soil. They can survive in dry soils but they are not active. However if the drought is severe, they will die. In dry conditions, they can burrow deep into the soil to 1 metre, tie themselves in a knot, secrete a coating of mucous about themselves which dries and helps prevent water loss.
As discussed in our Worms breathe through their skin blog – keeping your worms moist is key to ensuring they can effectively dissolve oxygen into their bloodstream through their skin. Your worm farm environment should maintain a moisture content range of around 60-85%.
When soils get dry, earthworms go into estivation. “During estivation, earthworms wrap their bodies into a tight knot to reduce the amount of surface area exposed to the soil,” explains Jacob McDaniel, lead author of the study in the September-October issue of Soil Science Society of America Journal.
They usually live in the soil's top few centimetres, but will burrow deeper to find essential moisture if the earth dries out or freezes. Worms are vital in maintaining soil structure and fertility as they aerate the soil, improve drainage and bring nutrients to the surface.
Silty soils with high water holding capacity and organic matter provide ideal habitat for earthworms compared to sandy soils, which have lower organic matter content and water holding capacity, and dry and reach uncomfortable temperatures quickly.
Earthworms breathe through their skin, which means they prefer loose, loamy soil. These worms also need soil rich in organic material and nitrogen. You can add a layer of lawn clippings over the soil to provide cool shade and nitrogen that attract earthworms.
When the rain hits the ground it creates vibrations on the soil surface. This causes earthworms to come out of their burrows to the surface. Earthworms find it easier to travel across the surface of the soil when it is wet, as they need a moist environment to survive.
They breathe through their skin. Air dissolves on the mucus of their skin, so they MUST stay moist to breathe. If worms dry out, they suffocate.
Worms love an environment with a moisture content of 70% or more. Food wastes usually contain about 80 per cent water and this will be released as the worms break down the food scraps. However, it will remain in the bedding for a long time before eventually draining out, so it's important to add water as well.
They have rings around their bodies and are pretty standard in outside soil. Red wrigglers are very cute, and sometimes they even come in potting soil. Researchers have found that earthworms benefit all plants because they promote soil aeration, recycle nutrients, and more.
You will soon see if your worm composter is too wet – it looks visibly sodden. To check pick up some of the made compost/bedding and squeeze… It should have the consistency of a wrung out sponge. If water leaks out between your fingers – then it's too wet.
Worms require a moist, dark environment in order to survive. Experiement #3 – Which surface will worms prefer? Collect the flashlights and give each group a dry paper towel. Instruct them to place their worms so that they are half on the wet surface and half on the dry surface.
Earthworms can also cause problems in the garden. Their burrowing can damage plant roots and make it difficult for plants to grow. This can cause harm to the plant's ability to take up water and nutrients from the soil and can ultimately lead to plant death. Hungry earthworms can stunt new plant growth.
An earthworm breathes oxygen by absorbing it through its moist skin. It likes damp soil, but if the rain is very heavy, the oxygen in the water-logged soil may run out. Then the worm has to come up into the air to breathe. On top of the wet ground, the worm can breathe and wriggle along.
A worm's skin is photosensitive and therefore they need a dark environment. Because worms have no teeth, they need some type of grit in their bedding that they can swallow and use in their gizzard to grind food, much like birds do with small stones.
Earthworms occur in most soils, but are scarce in soils that are extremely acidic or prone to water logging. There is no need to introduce earthworms as they are usually present at natural densities and will colonise new gardens. Earthworms eat decaying plant material and do not damage growing plants.
✓ Improved soil structure
Earthworms help loosen compact soil by creating tunnels as they wiggle about and eat, encouraging the movement of water, nutrients, and oxygen. Your turfgrass will struggle to grow if it can't drink, eat, or breathe, so it's always helpful to have these natural aerators in your lawn.
But after a rain, the soil pores and the worm burrows fill with water. Oxygen diffuses about a thousand times slower through water than through air, she says. “The worms can't get enough oxygen when the soil is flooded, so they come to the surface to breathe.”
Worms can live as long as four years. When worms die in the bin, their bodies decompose and are recycled by other worms, along with the food scraps. Worm castings are toxic to live worms. After all the food scraps in a bin are recycled, the worms will eat their own castings which will poison them.