At this point in the year, gardening becomes less about growing and more about what to do with the garden debris. Deadheaded flowers, fall leaves, vegetable peelings – all that “waste” can be used to bring new life to your spring soil through composting. An infusion of compost into spring soil introduces a nutrient- and microbe-rich source of humus that builds soil structure in your garden and gives life – essential microbial life – to your soil. But it’s important to create a welcoming table for those important organisms.
The “recipe” for compost is remarkably simple – and forgiving. No measuring, just some occasional mixing. Key ingredients for a successful compost bin or pile include:
Green Material: Fresh green matter like grass clippings, pulled weeds and vegetable plants or peelings provide lots of nitrogen and easy to digest sugars to support bacterial life. Green material also adds moisture to compost piles and bins. Take care not to have too much finely-chopped material (like grass clippings), because it can cause compost piles to compress and force out needed air.
Brown Matter: Aged brown organic material like fall leaves, bark and twigs have more carbon content to attract fungi to the compost. They can break down the lignin and cellulose in this material, making it available to bacteria to continue the decay process. With brown matter, you will want to break some of the larger branches into smaller pieces to give fungi a larger surface area to attack and jump-start the decomposition.
Air: Many of microbes in healthy compost need air to survive. It is important to turn compost every two weeks to mix old and new material and create space for ample air in the middle of the pile.
Moisture: Without ample water, microbes will start die off or go dormant, but too much water is detrimental too. Add a little water if you notice your compost is dry when you turn it, but cover it during a soaking rainfall. Think moist, not wet.
Heat: The center of a compost pile with strong microbial activity will naturally heat up to 135-150F within a week. This heat kills off pathogens and weed seeds. If your compost is not hot enough, turn the compost or add some fresh green material or newspaper to jump-start bacterial activity.
There are a few ingredients that can really wreck a compost pile, so steer clear of these harmful compost ingredients:
No Chemicals: Pesticides, herbicides, fungicides and chemical fertilizers can all kill off the microbial life your compost is designed to support.
No Human or Pet Waste: Make sure that your grass clippings do not include pet feces, which contain pathogens that might not get killed off by the heat of the compost.
No Meat, Dairy or Fats: Animal products and fats can attract flies and unwanted animals to your compost pile and spread disease.
To tell if your compost is ready, smell it. Once the compost looks like rich brown soil and you can’t identify the materials that made it, it is getting close. If it smells like ammonia, it’s not ready yet. Once it smells like sweet, fresh soil, it’s ready to spread on your garden to add a healthy infusion of microbial life to your soil. And of course, if you see plants sprouting up in your compost from seeds that have blown in, you’ll know it’s ready to support plant life!
For more composting solutions visit our friends at Urban Gardeners Republic.