How Compost and Rock Dust Work Together

Most of the plants that we tend to cultivate will do better if you provide them with a regular supply of nutrients. These nutrients will make your plants grow faster, bigger, and more nutritious. They will also be tastier and stronger. Stronger plants are better able to fend off bugs and disease. Plants grown in mineral rich soil will contain valuable nutrients which are delivered to those who consume them. In organic gardening nutrients are primarily provided to the plants in the form of compost and rock dust.

As the plants grow they use up minerals in the soil. Organic compost provides nitrogen to the plants. This is the most important nutrient because this is what makes the plants grow fast. Rock dust replenishes valuable trace minerals to the soil such as calcium, iron, magnesium, phosphorous, potassium, zinc, etc. in trace amounts. However, trace minerals such as these are structurally hard and difficult for the plants to assimilate through their root system without some assistance. Microscopic beneficial microbes that live in organic soil are capable of pre-digesting minerals making them more bioavailable to the plants. In addition to nitrogen organic compost also provides cultures of these beneficial microbes to the soil assisting the roots of the plants in up-taking trace minerals. If you are using city tap water in your garden it must be filtered so the added chlorine and chloramines do not kill off these beneficial microbes.

To provide your plants with a regular supply of nutrients you will need to “side dress” your plants with organic compost. Add about four cups of mature compost around the base of each plant once every two weeks throughout the growing season. Rock dust only needs to be applied to your garden once every three years sprinkled evenly at a rate of 14 pounds for every 100 square feet. You can make your own compost at home or you can purchase compost from a garden nursery or Home Depot. You can get rock dust at a local quarry or a local granite countertop company or online.

By Brian Hetrich, Greehouse Manager