Help keep the GardenZone free:

Forum

Tell a Friend about Us

Even Greener Products for your garden

Environment

Are You Overwatering Your Garden?
Make An Easy Coffee Can Bird House
How to Make Squirrel Proof Bird Feeders
Attracting Nesting Birds
Soil Basics - Creating Fertile, Healthy Soil
Mulching Benefits - Organic And Inorganic Mulch Types
UK Zone Map
How to attract bees to your garden
How to attract pest predators
Pest Control - Good Bugs
Companions & antagonists in the organic garden
Crop rotation
Mulching in the organic garden

Growing

Organic fruit cultivation table
Organic vegetables cultivation table
Organic herbs cultivation table
How to grow organic herbs
Culinary Herb Gardening
Grow your own salad
Sprouting seeds
Unusual fruits
How to prepare a seedbed
Organic crops sorted by family
Organic crops sorted by name
Organic crops sorted by difficulty
Everyone needs a spaghetti garden

Compost and Nutrition

Building a compost heap
Making loam and leafmould
Making worm compost
Best ways to use compost
Compost problems
Special compost mixtures
Green manures
C:N ratio of commonly composted materials
N:P:K analysis of compost materials
7 compost factors
Soil PH And Its Effect On Your Garden
Understanding Soil Nutrients

Kill or Cure

Traditional garden treatments
How to recognise mineral deficiencies in the organic garden
How to use organic fertilisers
Aerated compost tea

Ornamentals

The Beauty of Landscaping
Protecting Your Lawn the Organic Way
How to Grow Phalaenopsis Orchids
Identifying Houseplant Pests
Planning A Flower Garden
Perennials Versus Annuals
How to make a Meadow
Blue wild flowers for your garden
Buying A Conservatory In The UK
Tips For Spring Gardening
Which gazebo is right for you?
Fertilising ornamental plants
Rose gardening challenges
Right plant, right place

Other

A Hobby Greenhouse Will Get You Growing!
10 Free Gardening Products
Water Garden - Pond Pumps To Pump Up The Volume
Water Gardens That Upset The Neighbours
Useful addresses for organic gardeners
Organic garden glossary
What Family is that crop?
About organic seeds
Barrier hedging
How to Plant Hedges
Cooking garden produce
Storing garden produce
Storing seeds
Simple seed saving
Freezing garden produce
Why you should use Gypsum

Even Greener Products for your garden



Visit our Forum



About us

Links page

Add URL

Privacy

Disclaimer

Contact us

Green manures and Cover crops in the Organic Garden

Looking for something else?

The easiest way to add organic material to soil is to grow a green manure and then dig it in - no need to cart stuff to and from the compost heap! Green manures are an inexpensive, convenient source of organic matter, increasing water retention so you don't need to water so often and helping plants to get more out of the soil, so you save on fertiliser. They are often used as cover crops to stop erosion of valuable topsoil by wind and water in bad weather conditions.

You can also dig in grass clippings, which greatly improve the physical condition of heavy textured soils and provide much needed humus and nitrogen, before planting a second crop in a vacant plot. On very acid soil, add a little lime at the same time as you dig in the grass clippings. Give the area a week or two to get back to normal, then plant as usual. Many times, the second crop surpasses the first.

Types of green manure

Green manures basically break down into legumes and non-legumes. Legumes are valuable because they help fix large quantities of nitrogen from the air, making it available to plant roots. They also store moisture and send down deep roots that tap soil minerals, assist soil aeration and drainage and are attractive to bees. Some leguminous crops add anything up to 150 pounds of nitrogen per acre to garden soil, equivalent to approximately five tons of manure. Winter-hardy legumes are also often used in orchards to maintain soil fertility.

Non-legumes are good for short term production of bulk organic matter for the garden. They are usually sown in late summer or autumn and dug in the following spring, so as to clear the land for the growing season.

Mulching with green manures

Although all varieties of green manure can be dug straight into the soil, many can also be used as organic mulching material. Mulches such as rye grass offer nutrition for the soil, attract earthworms and keep the soil moist. And as the mulch decomposes, soil nutrients are released, so you get two effects for the price of one.

Soil improvement

Even poor soil can be improved with cover crops. Sandy soils gain moisture from the use of green manures; clay soils are helped by crops with long roots which soften the ground, such as alfalfa; and weedy soils can be cleaned up with fast-growing grasses to choke out unwanted weeds at the same time as adding nutrients. Green manures, treated carefully, will enable the soil to hold its nutrients until they can be used by the crops which follow. Cover crops are also beneficial to soils suffering from erosion or water build-up by providing erosion barriers to hold on to topsoil and absorb excess moisture.

Improving aeration and drainage

Green manures dug into the ground will greatly improve both drainage and air exchange in soils of good structure. The best way to maintain good soil porosity is to add organic matter to the soil by digging in green and farm manures, or adding compost to your soil.

Green manure crops

There are many green manures to choose from. Here are some of the more common ones:

¹ May be hit by a hard frost. ² Attracts hoverflies. ³ Inoculate seed