Soil Sunrise Horticultural Charcoal

Horticultural charcoal is pure, untreated hardwood charcoal without any added chemicals, accelerants, or binders. Grilling charcoal often contains additives that can be toxic to plants and disrupt soil pH, so you should never use it in your garden or terrariums.

It is safe for most indoor plants, but it is particularly beneficial for moisture-sensitive plants like orchids, bonsai, and succulents. It helps prevent root rot by improving drainage and keeping the soil environment fresh.

You can do both. Mixing it into your potting mix improves aeration and filters toxins throughout the root zone, while placing a layer at the bottom of a pot without drainage holes helps prevent water from stagnating.

Horticultural charcoal is generally pH neutral or slightly alkaline. While it won't drastically alter your soil's chemistry, it can help buffer acidic soils over time, making it a safe addition for most common houseplants.

In a closed terrarium, the charcoal acts as a long-term filter. You typically don't need to replace it unless you are completely refreshing the terrarium's soil and plants, which is usually done every few years.