Garden Fresh Salsa

Can You Add Garden Weeds to the Compost Pile?

Garden Weeds

One common question we get from people who are new to composting is whether it is safe to add garden weeds to the compost pile. The answer to this is yes and no. There are certain risks to adding garden weeds to the compost pile but some of these risks can be mitigated with the right techniques and conditions. Here are some of the things you should consider before you start mixing in garden weeds to the compost pile.

Type of Garden Weed

One of the first thoughts to consider is the type of garden weed you could be adding to the compost pile. Ideally, you should avoid any garden weeds that are known to be hardy and can tolerate difficult conditions. If the heat from the compost pile doesn’t kill the mixed-in garden weeds then you are opening up your lawn or garden bed for additional weed growth once the compost is added back to the soil.

Composting Method

It’s important for the compost pile to get hot enough to kill the seeds of the garden weed. For hot composting, you might be able to achieve a temperature between 141 to 155 Fahrenheit, which should be enough to eliminate weed seeds and harmful pathogens. Reaching these hot temperatures, however, isn’t so easy with a small compost pile so this is something you will need to account for in the planning process. Some people like to use the cold composting method, which is a lot easier to maintain than the hot composting method. Cold composting, however, won’t kill off the garden weed seeds so you should not be adding garden weeds, especially invasive ones, if you are using that kind of composting method.

Fool-Proofing Weed Killing Method

If you think there could be a likelihood of your compost pile not getting hot enough to kill the seeds then there are some approaches you could take to ensure they do get eliminated. One approach is the baking method and this works in places that get plenty of warm heat from the sun. Before you add the garden weed to the compost pile, you will first lay the roots of the perennial weeds on concrete (or any other material that keeps them off the soil) then allow the summer sun to dry the roots out for about two to three weeks. You should be able to add the garden weeds to the compost pile once the roots have been completely baked.