Do You Need Light to Grow Mushrooms?: Discover the Truth About Mushroom Growth and Light Requirements

Mushrooms, unlike green plants, do not rely on photosynthesis for their growth, so they do not require light in the same way that plants do. However, light does play an important role in certain phases of mushroom development. During the initial stage—mycelium growth—mushrooms thrive best in darkness, as light is not necessary for the expansion of the underground network of fungal threads. Yet, when it comes time to fruit and form the actual mushrooms you see, many species require some exposure to indirect or diffused light to trigger proper development, shape, and color of the fruiting bodies. Insufficient light may result in mushrooms that are pale, elongated, or malformed, while too much direct sunlight can dry them out or inhibit growth. In general, ambient room light or filtered sunlight for a few hours a day is sufficient for most home mushroom-growing setups. Ensuring proper humidity and airflow is just as important as light for robust mushroom cultivation.

Tips 1:

As a designer, I find that successful mushroom growing is much like planning effective interior lighting. It’s all about balance—too much or too little light can affect outcomes. If you’re building a grow space or repurposing a room for cultivation, consider using shade cloths, frosted panels, or even adjustable LED strips to mimic the gentle, indirect light mushrooms need. For those seeking a harmonious multi-purpose space that supports both plant and fungi life, integrating flexible or dimmable solutions through a room planner can help ensure optimal conditions for every occupant—whether they have roots or mycelium.

FAQ

Q: Do mushrooms need complete darkness to grow?

A: Mushrooms need darkness for the initial mycelium growth, but to fruit and form healthy mushrooms, they require some indirect or diffused light.

Q: What type of light works best for fruiting mushrooms?

A: Cool white fluorescent, LED lights, or natural ambient light (not direct sunlight) work well for mushroom fruiting stages.

Q: Can mushrooms grow under normal room lighting?

A: Yes, most mushrooms will fruit just fine under standard room lighting as long as it's not too intense or direct.

Q: What happens if mushrooms don’t get enough light?

A: Inadequate light can lead to poorly formed mushrooms that are pale and elongated, impacting both appearance and yield.

Q: How many hours of light do mushrooms need a day?

A: Around 12 hours of indirect light per day is ideal for most mushroom species during the fruiting stage.