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Got a compost pile?
Watch out for certain weeds!
These 3 weeds can ruin your compost if you’re not careful.
Want to know which ones to avoid?
Keep reading to keep your compost healthy!
Is Composting Weeds A Good Idea?
Weeds can actually be composted under certain conditions, and doing so can offer some benefits for your garden. They can help with moisture retention and improve soil fertility.
Some weeds, especially those that have gone to seed, invasive species, or those that can easily regrow, might cause issues if added to compost. It’s important to pick the right kind of weeds for composting.
To speed up the decomposition process, you should shred the weeds into tiny pieces. This can be done using a lawn mower or pruning shears.
Preferably, use annual weeds before they set seeds. Avoid weeds that have already produced a large number of seeds to prevent them from spreading in your garden.
Interestingly, some gardeners choose to let weeds grow naturally. This can promote biodiversity, enhance soil quality, and conserve water. However, weeds can spread quickly, so it’s important to manage their growth to prevent them from taking over.
How Long Till Weeds Decompose?
You might be curious about how long it takes for weeds to break down in compost. Typically, it takes about two years for weeds to fully decompose.
Decomposition is a slow process that involves worms, sowbugs, and other soil microbes breaking down the organic matter. To speed up this process, chopping or shredding the weeds into smaller pieces is recommended.
The type of organic waste and whether it’s being composted in a bin, heap, or tumble composter also affects the decomposition rate.
Every composting setup and weed type can differ, so there’s some variability in how long the process takes.
Weeds You Should Never Compost
1. Bindweed
Avoid adding bindweed to your compost. This persistent perennial weed has invasive roots and can grow up to 3 feet tall. When you compost bindweed, its seeds can germinate and infiltrate your compost, ruining it. The best method to dispose of bindweed is through a garden waste bag because it can even penetrate through lawn grass.
2. Japanese Knotweed
You shouldn’t compost Japanese knotweed due to its rapid growth and invasive nature. This perennial can grow about 4 inches daily and reach a height of 9 feet. It spreads aggressively through its rhizomes and can damage nearby plants and structures in the garden. Because it is so difficult to eradicate, it’s best to call a professional for help with knotweed control.
3. Dandelions
Be cautious with dandelions. If you include dandelions in your compost with their roots intact, they can regrow in the pile. For example, red-seed dandelions can begin to flower just 8 to 12 weeks after their seeds sprout. To avoid this issue, ensure the roots are removed before composting.