Weedy Wednesday - Composting Weeds

Our final Weedy Wednesday article offers advice on how to harness the valuable nutrients from weeds. With care, you can compost them, roots and all. Here we tell you how:

Composting perennial weeds

Most composting advice suggests that only weed foliage is added to the heap, without roots attached. This is because the domestic compost heap usually doesn't achieve sufficient heat to break down the tough root fibre. Therefore, when you come to spread your newly-made compost, it will probably contain root sections of perennial weeds such as bindweed and ground elder - both of which can propagate from root sections.

You can add the roots to your local council green bin collection. Their composting facilities achieve a heat high enough to rot down the most persistent plant fibres. Or, you can capture the valuable nutrients in these roots - by drowning them!

Immerse the roots in a bucket of water for a few weeks; use a brick to weigh them down and ensure they stay fully submerged. Once the roots have started to decay, they can be added to the compost heap and the foul-smelling but nutrient-rich liquid can be used as a feed for container plants.

Roots can also be dried out by leaving them to 'bake' in the sun before being composted (an old piece of corrugated metal in full sun gets extra hot). Make sure the roots are fully desiccated, and before drying, hit the weed roots with a hammer to crush their structure. This can be quite a therapeutic activity!

Weeds with seeds

If you don't manage to catch your weeds, such as dock or thistle, before flowering and setting seed, these too can be drowned along with perennial weed roots. This prevents most seeds from being able to germinate.

See here for further information on how to prevent and manage weeds.