When gardening, an essential factor in plant health is the soil type. Topsoil is prized for its nutrients and organic matter, making it an ideal growing medium. However, it isn’t the only medium that’s suitable for gardening and planting as cinder soil offers several benefits.

What’s Cinder Soil?

This material is a blend of cinders and dirt. Cinders are crushed volcanic rocks formed during the cooling and depressurization process of a volcanic eruption. Their bubble-like cavities, called vesicles, allow them to float in water. Depending on chemical composition, cinders can appear red, black, or brown.

Adding cinders to topsoil yields a product called cinder soil. Depending on your needs, the ratio of dirt to cinders can vary. Some gardeners use a mix that’s half cinder and half soil, and others increase the ratio to 60:40, adding more cinders for better soil aeration and root development as well as more drainage capacity.

Why Use Cinder Soil

While quality topsoil contains organic matter that’s essential for plant growth, adding cinder to the mix can significantly improve its nutrient-retention. The vesicles and amorphous minerals, like allophone and imogolite, found on the cinder are notable for adsorbing organic matter, which is necessary for plant growth.

Some cinders are steamed to sterilize them, removing any unwanted pests and nematodes residing inside the rocks. Although nematodes play a role in breaking down organic matter for richer soil, a few of their species can also damage plants and infect them with fungi and diseases.

If you need cinder soil for your project, contact the team at Sanford’s Service Center in Pahoa, HI. Since 1977, these professionals have provided Big Island residents and businesses with quality construction materials, including gravel, aggregates, topsoil, and ready-mix concrete. View their products online, or call (808) 965-8144 to request a service estimate for material hauling and land clearing.