Green manures - use plants to feed plants
Grow your own fertility with green manures
Green manures are plants that are grown to improve the soil in organic gardens. They can suppress weeds, improve the soil structure, prevent evaporation and soil erosion and even make the soil more fertile than it was before - you just need to choose the right green manure for your situation.
How to choose a green manure
Choose the right green manure to sow
There are many different plants that can be used as green manures. When you decide to grow one, you need to choose the right green manure for your garden.
In the spring time choosing a green manure depends on how long you want it to be in the ground for, why you're sowing it and your crop rotation. Follow the link to find out more.
If you want to sow a green manure in the fall, then choosing is easy - there aren't many that will grow overwinter! Read my article on green manures for autumn, or listen to episode 27 of The Alternative Kitchen Garden show.
How to use green manures in your garden
Find out how to grow green manures
Once you've chosen your green manure, it's time to grow them. It's an easy, low maintenance process.
Check out how to grow green manures.
Drink your green manure
A lot of people use clover as a green manure - it's easy to grow, makes a good ground cover to suppress weeds and fixes nitrogen in the soil to fertilize your next crop. But if you allow your clover to flower then not only will you encourage bees into your garden, but you can turn those flowers into a lovely, healthy herbal tea, as they do over at Subsistence Pattern.
The Green Manurista - How to dig in your green manures
A low-growing green manure
Trefoil is unusual as a green manure because it is used while other crops are still in place.
Trefoil is very low growing, and adds nitrogen to the soil, so it makes a great living mulch. Sow it under hungry plants like fruit bushes in spring.
It also helps to confuse the cabbage white butterfly, so sow it underneath brassicas.
Hungarian grazing rye
Hungarian grazing rye is an excellent green manure to sow if you have heavy soil that needs breaking up. Grazing rye has strong, deep roots that can relieve soil compaction and improve soil structure.
Hungarian grazing rye can be sown from early spring right through until late autumn, and is one of the few green manures that will overwinter and protect the soil from winter weather.
It's not bad at preventing weeds either! The only downsides with Hungarian grazing rye is that is can be tough to dig in, and for a few weeks after being dug in it will prevent seed germination - so don't sow seeds there for a few weeks.
The organic gardener's best friend
Comfrey is a perennial plant, and so doesn't fit the profile of a conventional green manure. However, it is grown specifically to provide fertility for the organic garden.
Comfrey leaves can be used to line the planting holes for potatoes and get your crop off to a good start. Comfrey can be made into a rich liquid feed that your fruiting vegetables will love. And if that's not enough, bees love it's flowers.
Learn more about comfrey in episode 7 of The Alternative Kitchen Garden podcast.
Buckwheat can be sown from late spring until late summer, and is left in place for 1-3 months. It doesn't fix nitrogen in the soil, but it thrives on poor soils which are badly in need of improvement.
To improve the soil, Buckwheat should be dug in before it flowers. However, leaving a small area to flower can also be beneficial because the flowers will provide a food source for hoverflies and other beneficial insects.
Where to buy green manure seeds - Online seed stores to try
If you have a link to add to this list then please leave a comment
- Suttons Seeds
Suttons sell a wide variety of flower and vegetable seeds, together with some green manures
Vegetable & flower seeds and plants
- The Organic Gardening Catalogue
The catalogue for organic and environmentally friendly gardeners - organic seeds for vegetables, heritage and modern varieties, herbs, flowers and green manures, organic composts and fertilisers, biological pest controls, organic gardening books and
- Kings Seeds
Welcome to Kings Seeds, a leading supplier of vegetable, flower, herb and Sweet Pea seed, from the traditional home of the British seed industry, Kelvedon, Essex, who have been supplying commercial and retail growers since 1888.
- Tuckers Seeds
Tuckers Seeds offers you a unique opportunity to browse through and purchase our products securely online. We have a vast range of seeds for vegetables, flowers, lawn, amenity grass, onions, shallots, potatoes, mushrooms, fruit and miscellaneous item