Keeping your soil healthy and fertile is the most important thing for the success of your garden. Healthy soil means better yields, lower pests and diseases, and more nutrient-dense vegetables (The Point of Having a Garden!)
While amending soil is a complicated, misunderstood, and often controversial topic among gardeners, there are three simple things to know:
- The best time to amend your soil is in the fall. The winter gives time for soil microbial life to break down organic matter and digest other minerals, making them available to the plants. If you didn’t amend in the fall, still do it in the spring.
- Get a soil test. A professional soil test will cost about $30, and can save you hundreds of dollars in the long run. It’s always useful—and interesting—to know what exactly is in your soil.
- Adding compost or manure isn’t always the best soil amendment option for organic raised bed gardens. Compost beautifully represents how a closed-loop system can work – with dead organic matter decomposing and turning into loose rich fertility for plants. However, large amounts of compost can increase salinity (specifically sodium) and potassium to unhealthy levels. If you’re going to use compost, consider making it in your backyard or do your research to find a high quality compost to purchase that is low in sodium. We recommend only adding about 1-2″ of compost to your garden each year, not more. If you are using manure in your garden, make sure it is well aged, or till a light amount into your garden in the fall to allow it all winter to age and break down.
So What Should You Do?
The Urban Farm Company offers the following mix, which is usually a good across-the-board amendment if you haven’t gotten a soil test:
- Mineral rock dust (Contains many of the 60 minerals necessary for healthy plants)
- A Slow-Release N-heavy Organic Fertilizer (Nitrogen is the fastest nutrient to leach out of raised beds, add in the spring before planting)
- Humate fertilizer (Acts as an organic binding agent and microbial stimulator)
- Mycorrhizae and other bacteria inoculants (Fungi and bacteria drive the entire soil-plant system. These should be added in the spring before planting.)
If you are using existing topsoil that hasn’t been amended with compost in the past, then you can probably go a little heavier than the 1-2″ recommendation that we have for raised bed gardens.
Amending Clayey Soils
If you have very clayey soil, the best option is to plant a cover crop in the fall, and till it into your soil in the spring. Or, mix a large quantity of leaves into your garden in the fall. Finally, adding peat or coco coir is a good way to break up the clay.
Too Confusing?Get in touch and we’ll test and amend you soil for you. No worries, no hassle.