Growing Advice: Green Manure for raised beds and heavy clay                          

One of our Sow Seeders is wanting to use green manure to tackle two different aspects in their vegetable plot...

The first is a raised bed that needs a quick-growing solution to enable crops to be sown by the end of summer. And the green manure of choice for this is Buckwheat. A quick grower and no need to fit into crop rotation plans...

raised bed sown with buckwheat green manure

Buckwheat is a fast-growing short-term summer green manure that germinates in about 3-5 days. It produces a dense canopy of foliage that smothers & out competes weeds and once dug into the top layer of soil (15-18cm) rapidly decomposes helping to improve the soils structure & organic matter content.

The second challenge is a much more common problem and one which we get asked on a regular basis...how can green manure help with heavy clay soil.

heavy clay soil fodder radish green manure

The green manure choice here is Fodder Radish. Fodder Radish is part of the brassica family so needs to be built into a crop rotation plan accordingly. 

Fodder Radish is a very quick growing green manure. It germinates in about 3-10 days depending on soil temperature. It has the ability to draw up nutrients from the subsoil and also penetrate compacted soils with its strong deep-rooting tap root.

Fodder radish also produces large amounts of foliage which when incorporated into the top layer of soil adds lots of leafy organic matter and helps it improve its moisture-retaining capacity, fertility and soil structure.

Fodder Radish also contains chemicals that help suppress nematodes e.g. cyst nematodes which attack potatoes.

The Fodder Radish can either be cut down on flowering or allowed to die back naturally through winter, used as a mulch and dug in during early spring. If it becomes too long it can be topped to about 20cm and allowed to re-grow.

We will keep this page updated with progress over the next few months.