The red wiggler worm is one of the most valued species for composting and improving agricultural soils thanks to its ability to transform organic matter into high-quality humus. Proper care ensures efficient vermicomposting processes and a sustainable production of natural fertilizer. Discover everything you need to know to keep them healthy and productive in your worm bin, from their characteristics and diet to the best practices for managing them at different times of the year.
What is the Californian red worm?
Scientifically known as Eisenia foetida , the red wiggler (Eisenia foetida) belongs to the Lumbricidae family and originated in Europe. Despite its name, it is called the California red worm because its use in vermicomposting became popular in California after its enormous potential was discovered.
This species is used in 80% of humus production facilities worldwide, thanks to its resilience, rapid reproduction rate, and ability to process large quantities of organic matter. It is important not to confuse it with Eisenia andrei, a different species in appearance and with a different production capacity.
Characteristics of the Californian red worm
- Color: very bright dark reddish.
- Adult size: between 3 and 8 cm long and 3 to 5 mm in diameter.
- Weight: between 0,25 and 1,5 grams when ripe (the usual is 0,4 – 0,5 grams).
- Reproduction: very prolific, capable of doubling its population every 3 months under optimal conditions.
- Longevity: They can live up to 4 years in controlled environments and just over 1 year in open fields.
- Light Sensitivity: They cannot tolerate direct sunlight, which can be fatal in just a few minutes.
- Breathing: cutaneous, through their moist skin. They require an environment with humidity above 70%.
- Sexual maturity: reaches maturity at 90 days.
These earthworms are hermaphrodites with insufficient reproductive organs ; they possess both sexes but require another worm to reproduce. They produce up to one cocoon or egg every two days, from which between 2 and 5 worms hatch after 21 days, allowing for very efficient population growth.
Properties and physiology
- They have no eyes, but they are highly sensitive to light and vibrations.
- They lack teeth and stomach, so they ingest food in a gelatinous and crushed state.
- They have no traditional heart, but they have 5 pairs of aortic arches that pump blood.
- They breathe oxygen through your skin, which is why environmental humidity is crucial.
- They move with the help of small circles (setae) that surround its body, facilitating movement and the excavation of tunnels that aerate the substrate.
- Your mucus secretes nutrients such as nitrogen, which are essential for plants.
- They are cold-blooded animals, therefore the ambient temperature determines its activity.
- Under optimal conditions they can produce up to 1.300 worms per individual per year.
Up to a million earthworms can live in plots of 4000 m², contributing significantly to soil fertility and aeration.
History and ecological relevance
Earthworms have been admired since antiquity. The ancient Egyptians revered their role in the fertility of the Nile. Aristotle called them the "intestines of the Earth" because of their important role in the nutrient cycle. Charles Darwin delved into the study of earthworms and published fundamental scientific works on their biology and benefits to soils, laying the foundation for modern vermiculture.
In the Americas, its industrial use began after the efficiency of Eisenia foetida populations brought from Europe was observed. Although its origin is European, the "California" variety owes its name to its expansion and popular recognition in California.
Optimal conditions for the Californian red worm
- Humidity: Ideally, between 70% and 90%. Less than 55% can cause desiccation and death, and excess water causes suffocation.
- Temperature: It is optimal to keep them between 15°C and 25°C, although they can tolerate ranges of 12°C to 30°C. Below 10°C, their activity and reproduction decrease, and above 35°C or below zero, they are at risk of dying.
- Alkalinity: Substrates with a pH between 6 and 8 are suitable. The action of the worms tends to stabilize the pH towards neutrality.
- Darkness: essential to avoid stress and damage. Keep the worm bin covered or in a dimly lit area.
- Ventilation and drainage: essential to prevent flooding and the accumulation of harmful gases.
- Tranquility: Handle them only as necessary, especially to check humidity or add food.
Feeding of the Californian red worm
Earthworms consume their own weight in food daily, provided conditions are suitable. They feed on decomposing organic matter , preferably shredded and moistened to facilitate digestion. The best foods are scraps of fresh and sweet fruits and vegetables (such as bananas, avocados, pineapples, and watermelons), eggshells, previously composted pruning waste, manure from herbivores (horses, cows, sheep, goats), and shredded paper or cardboard without chemical inks.
Horse manure is especially appreciated for its high cellulose content and for not compacting, facilitating the movement of worms. Cow manure is also excellent, and sheep and goat manure should be accompanied by materials rich in plant fiber. Avoid feeding them meat, fish, oils, cooked leftovers, dairy products, plastics, and highly acidic or spicy foods. Citrus fruits, tomatoes, onions, and coffee should be added in moderation.
Care and maintenance throughout the year
- Winter: Protect the compost bin indoors (garage, basement) or use insulation with polystyrene or thermal blankets. Maintain ventilation to prevent excess moisture.
- Summer: Place it in cool, shaded areas, ensuring sufficient humidity and preventing the substrate from drying out.
- Avoid sudden temperature changes: Move the worm bin gradually if necessary.
- Covering material: Add a layer of dry leaves, paper or cardboard to stabilize the internal temperature and humidity.
- Regularly monitor: Check the condition of the substrate every week, adjusting humidity and food type as needed.
Collection and separation of humus
After a few months, the humus will be ready to be collected. To separate the worms from the compost, simply stop feeding them for two or three weeks and place the food in only one specific area of the vermicompost bin. The worms will migrate to the new food, making it easier to collect the clean, mature humus. It's recommended to let the humus air out to reduce its humidity to 50%, preserving its nutrients for a long time.
Caring for red wiggler worms involves paying attention to humidity, temperature, food, and their environment. If you provide an optimal environment and follow these recommendations, your worms will efficiently transform organic waste into high-quality humus, contributing to environmental care and the nutrition of your plants.
