What is Green Manuring? Can I use it at home?

1- Introduction to green manure

If you visit the tulip fields of the Netherlands in mid summer there won’t be much to see. This time of year is about the preparation of dry bulbs lifted in early summer. The bulbs are sorted into planting stock and selling stock. The flower bulbs you receive in autumn have been grown to a certain size. They are cleaned, counted and packaged ready to send in September onwards. Smaller bulbs are replanted in autumn to put on size ready for the next year. Removing the flower heads helps the bulbs grow for the next season.

However, constant farming of the same field can cause soil erosion. Particularly when the fields are flat and sandy, such as the dutch fields of Hillegom. Many of the nutrients can run off into the abundant water ways. So increasingly you will see fields filled with grasses.

There has been a massive increase in the use of Green Manuring. This is a method of planting a quick and easy to grow crop to cover the soil whilst it is not in use. 

Rye grass is planted in the fields between the bulb harvest and before autumn planting of bulbs. 

This particular crop grows roots 3-4 feet deep, bringing nutrients to the surface for the new crops.

Planting green crops helps reduce the runoff of soluble nutrients, maintains the soil structure and smothers weeds. 

The crop is then worked into the soil providing nitrogen and organic matter. 

It is a great way of using organic material to work in harmony with the land. It is actively encouraged in the Netherlands. With 14800 hectares of tulips grown in the Netherlands, it is a fantastic step forward in the way we approach mass farming techniques, tackling issues such as soil infertility and erosion. 

2. What seeds can be used for Green Manuring?

You can use the following

• Mustard seed (but this can cause rot from the roots)
• Phacelia
• Clover 
• Legumes - beans and peas

You can see more about Green Manuring here 

3. Can you use Green Manuring at home?

Yes, definitely. It is a brilliant was of keeping nitrogen in your soil. Nitrogen is an essential element for a healthy crop of flowers.

It is regularly used in the UK by organic farmers and on allotments. 

This year we are experimenting with growing clover on our beds. It is easy to work over in spring. Rye grass can be hard to manage on a smaller plot. Particularly without the use of machinery and without damaging plants you want to preserve. 

The new growth should help suppress most weeds. 

Grasses will continue to grow over winter maintaining your soil structure and giving bugs a place to hide. 

Working the green plants into the soil will release nitrogen and other nutrients that may have been lost by leaving your soil exposed. Leave for two weeks so any dying matter wont choke any new plants.