What to do with wet compost

What is green compost?

Green compost comes from roadside collections of home gardeners green or brown bins. This is where you put garden waste such as grass clippings, leaves, stems and spent flowers. The bins are collected and then taken to composting yards where the material is sorted and shredded before being put in extremely large rows. Whilst in these rows, the composting process starts where the organic material is broken down through aerobic activity (breaking down of all the organic material).

Aerobic activity needs air (oxygen) water (rain), warmth and food to take place and as long as these are present, the microorganisms present, then break down the material into the renewable ingredient used in peat free composts.

For aerobic activity to be successful, the material needs to be turned regularly so that the microbes can work efficiently and break down the waste, creating heat to kill weeds and diseases in the process.

As well as the garden waste collected, unwanted, inorganic materials are sometimes put into the bins, such as broken plastic plant pots, bags, labels, or fence nails. These materials will not compost and have to be removed. Firstly, by sight as the rows are turned and then by machinery.

Once the composting process is completed outside, usually 6-8 weeks, the material is then put through industrial sized sieves and magnets to remove any of the inorganic waste.

Why compost can be wet?

As aerobic activity needs to take place outside, the process is impacted by the weather and length of storage time. If there has been unprecedented rainfall during the year and gardeners are understandably not gardening, the compost has to be stored in these wetter conditions for longer, meaning clumps and lumps can form within the compost as the waste breaks down.

Why have I found foreign items in my compost?

Wet compost can sometimes make it difficult for the sieves and magnets to work to full efficiency and occasionally some unwanted objects remain hidden inside a clump of compost during screening, so can then end up in the finished bag of compost.

Although this is extremely rare, we recommend you always wear gloves when handling compost and dispose of any unwanted items safely.

Why can compost be smelly?

As with most things that get wet it can have a stronger smell, (think wet dog!) and compost is no exception. After a wet winter, the natural materials that go into peat free compost can often have a stronger smell than usual. However, the smell is nothing to be worried about and is a natural occurrence due to wet compost sitting in a plastic bag. The compost is still fine to use but can benefit from being opened and allowed to air in drier conditions for a couple of days.

Tips on using wet compost

• If using in pots or containers, open the bag and pour into a shallow bucket to allow it to dry out for a bit.
• Wet compost is often cold and can slow down growth. By drying it out and placing indoors such as a shed or garage, the compost will warm up. We recommend that you always bring your compost to the same temperature as the growing environment before use, but store in a cool, dark place.
• Occasionally you may see white mould in the damp compost, this is not harmful to you or your plants but by mixing the compost while applying, it will soon dissipate.
• Start feeding your plants earlier. With very wet compost, it may mean that nutrients have been leached out (washed away) especially if the compost bag has been left outside for a while. Earlier feeding is recommended. You can use a granular or a liquid feed such as Miracle-Gro All Purpose Concentrated Liquid Plant Food.