Lasius niger
(Linnaeus, 1758)
Black garden ant
Temperature
20–26 °C
Humidity
50–70%
Colony size
5,000–15,000
Queen size
8–10 mm
Worker size
3–5 mm
Hibernation temp
6 °C
Diet
Care Guide
Lasius niger, commonly known as the black garden ant, is a classic introduction to the world of ant keeping. The queen is a modest 8–10 mm in length, while her workers range from 3–5 mm and are uniformly dark brown to black. Unlike some species that display striking physical castes, *Lasius niger* colonies are monomorphic — all workers are similar in size and shape, yet they perform a remarkable variety of tasks with tireless efficiency. This species is renowned for its rapid colony growth and adaptability, making it a favourite among both newcomers and seasoned keepers.
Their diet is straightforward: these ants thrive on a mix of protein and carbohydrates. Live or pre-killed insects such as fruit flies, mealworms, or small crickets provide essential protein for brood development, while sugar water or honeydew satisfies their constant need for energy. A steady supply of both will keep your colony active and growing. They are enthusiastic feeders and will quickly swarm any offered food, a behaviour that is a joy to watch.
Care difficulty
Keeping *Lasius niger* is perhaps the easiest way to start your ant‑keeping journey. They are extremely hardy, tolerate minor fluctuations in temperature and humidity, and forgive the occasional keeper error. A temperature range of 20–26 °C suits them well, with a slight drop at night being perfectly fine. Humidity should be kept between 50 and 70 %; a moistened section of the nest and a water source in the outworld will suffice. The most important requirement to remember is hibernation: from late autumn to early spring, these ants need a cool period of around 6 °C for several months. Skipping hibernation can weaken the colony and reduce queen lifespan. A garage, unheated cellar, or a specialized mini‑fridge works well.
Housing
A small test tube setup is ideal for the founding stage, but as your colony expands you will need to provide a larger formicarium. *Lasius niger* is not particularly demanding about nest material — acrylic, plaster, or sand‑clay mixes all work. The outworld should be escape‑proof and large enough to accommodate foraging trails. Keep the nest area relatively dark and undisturbed; these ants appreciate stability. Regular, gentle moisture in the nesting chamber helps larvae develop. Because colonies can reach 5,000–15,000 workers, plan ahead for modular expansion.
First days after purchase
Upon receiving your *Lasius niger* colony, place the setup in a quiet, dimly lit room and allow the ants to settle. Do not disturb them for at least 24‑48 hours — they need time to adjust to their new environment. Ensure the water source is accessible and offer a small drop of sugar water on a cotton pad. Avoid bright light and vibrations during this acclimation period. Observe from a distance; you will soon see workers exploring and tending to the queen. Once they are moving confidently, you can gradually introduce insect prey. Remember that patience pays off: a calm start leads to a thriving, long‑lived colony.