It appears you do not have Javascript enabled in your browser. Javascript must be enabled for our website to display and function properly.
Free Seeds On Online Orders Over $50

Using Cover Crops as Green Manure

Sep 21, 2009 -
  Using Cover Crops as Green Manure
This cover crop is half tilled in as green manure.

by Amber TIppett, PV Store Manager & Willow Hein, FreshmanFarmer &  PV employee

“Cover Crop” is a general term referring to a crop grown to cover and protect the soil.  The term “Green Manure” would more specifically apply to a Cover Crop grown with the intent to till back into the soil.

Below we’ve outlined a few Cover-Crop-as-Green-Manure suggestions for clay or compacted soils, and vegetable bed rotations. Looking for more solutions? Check out our Cover Crop Solution Finder.

bell beans

Cover Crops (or “Green Manure” crops) for Clay or Compacted Soil

Planting cover crops is an excellent way to help break up compacted and clay soils.  Plant something with a large taproot, or deep-reaching root system that can penetrate the hard soil or compacted soil pan.  Examples of these include Bell Beans (SCL700), Winter Rye (SCN395), Rape (SCN900), Daikon (SCN112) and Mustard (SCN755 or SCN750).

You’ll want to plant these cool weather crops in the fall, after the first rains, when the soil is softer and can be tilled and prepared for planting.  The cover crops will grow all winter, and can be turned in during the spring to add organic matter to the soil.  The cover cropped area could then be planted with vegetable or ornamental crops, or planted with a summer cover crop to continue breaking up the soil if it is still compacted.

crotolaria juncea hemp An example of a good summer cover crop for this purpose is Crotolaria Juncea (SCL815).

You will need to irrigate this crop through the summer if you live in an area where it doesn’t rain.

organic soil builder svm121

Cover Crops (or “Green Manure” crops) to Plant in a Vegetable Rotation

Planting a winter cover crop is a great way to replenish your soil after a season of vegetable or production cropping.  You want something that will fix nitrogen back into the soil, hold the soil in place during winter storms, and grow vigorously for maximum organic matter and weed suppression.  Peaceful Valley carries a great cool weather cover crop mix (Soil Builder SCM120, SCM121) which contains bell beans, winter peas, purple vetch, common vetch, and cayuse oats, a blend that addresses all the above-mentioned needs.

The bell beans, peas, and vetches are legumes that fix nitrogen from the air through a symbiotic relationship with a group of naturally occurring soil bacteria known as rhizobacteria.  The bacteria form nodules on the roots of the plants and convert gaseous nitrogen into plant-usable nitrogen.p>

Be sure to inoculate (ISE350, ISE505, ISE500) your seed with the rhizobacteria before you plant it to make sure this process happens in your cover crop.  The oats provide scaffolding for the vetch to climb up and have fibrous root systems that suppress weeds and help with erosion control.  Other great cover crops for the winter include clovers and alfalfa.

Green Manure Saves You Money

Check out our blog post that shows how much cheaper it is to plant cover crops than buy fertilizer.

Solutions: Adds significant organic matter, Attracts beneficial insects, California native, Cold hardy, down to 25°F, Easily established, Fixes nitrogen, Germinates in soils < 45°F, Good for forage or hay, Good weed competition, Helps Control Erosion, Loosens heavy soils, Low-growing, to 12", Mid-height, 13 to 36", Nematocidal effects reported, Provides quick growth, Requires summer water, Shade tolerant, Somewhat drought tolerant, Tall, over 36", Tolerates mowing/grazing, Tolerates poor drainage

Categories: Grass Seed, Perennial Grass Seed, Fescue Grass Seed, Cover Crop, Annual Cover Crops, Cereal Seeds, Erosion Control, Green Manure, Inoculants, Perennial Cover Crops, Pasture Seed, Dryland Pasture Mixes, Irrigated Pasture Mixes, Organic Gardening 101

jennie Says:
Sep 30th, 2009 at 12:37 pm

what is the shelf life of the inoculants?

Andrew @ Peaceful Valley Says:
Sep 30th, 2009 at 1:15 pm

“Hey Jennie-
Inoculant that is stored properly (should be stored in ““pantry-like”” conditions - dry mild temperatures) should be viable for 12 months.  Keep in mind that this is a living organism and for this reason it is important to make sure you store it with this in mind.

Hope this helps!!”

Tom Says:
Oct 27th, 2009 at 4:11 pm

“This has been moved here - for the sake of visability
(Andrew @ Peaceful Valley)

Hey I just bought some crop.  I heard raking it in was a good idea.  I did this but it was soooo time consuming.  I got out my tiller and set it to a very very shallow setting and quickly moved it through.  I have planted rye and clover the seeds are pretty small.  There’s only about a quarter inch of soil on the seeds some being closer to the top than others.  Is this a problem?”

Questions & Answers: Organic Cover Crop and Ti Says:
Oct 28th, 2009 at 7:24 am

[...] was posted as a comment on Cover Crop Solutions.

Cherri Nordin Says:
Oct 23rd, 2010 at 1:17 am

Long time viewer / 1st time poster. Really enjoy reading the blog keep up the excellent work. Will definitely start posting more often in the future.

Josh B Says:
Jun 9th, 2012 at 2:06 pm

I’ve started turning several areas of my yard into garden (3 so far) and the rest is mostly dead grass and weeds.  The soil is mostly compacted clay.  I’m wondering if I can plant a cover crop (a mixture, I’m assuming) over the entire yard instead of just the areas I’m already gardening, because I plan on turning more and more of the yard into fruit and vegetable gardens.  Is this advisable or should it be done in sections or something else?

Thank you for your great site and products!

Charlotte, Peaceful Valley Says:
Dec 29th, 2012 at 11:39 pm

Josh B, Yes, there is nothing wrong with building your soil by planting cover crop over large areas. If you will be turning it in as green manure you need to reserve time for all that work, though. Turn in green manure when about 1/2 of the stalk has bloomed.

Peter M Warren Says:
Dec 27th, 2014 at 9:28 am

I have your soil builder planted since late november in Los Angeles coastal area.
How long should i let it grow before turning under?

Suzanne at Peaceful Valley Says:
Dec 29th, 2014 at 12:58 pm

Are you already getting flowers? When the plants start to flower is a good time to till under.

Art Norman Says:
Mar 2nd, 2015 at 2:19 pm

You used to carry a product called voodoo brew.  It helped the green manure to break down much sooner before tilling it in.  Is there an alternative product that does this?

Suzanne at Peaceful Valley Says:
Mar 6th, 2015 at 11:18 am

Yes, we stopped carrying that product and don’t really have a direct substitute. You can try using the Dr. Earth Compost Starter or the other compost inoculants that we carry. They all contain strains of bacteria, fungi and/or enzymes that speed up the breakdown of the bio matter.

Randy Ketner Says:
Apr 5th, 2015 at 6:37 am

I am going to sow buckwheat and red clover on a section of my garden to see if it helps control johnson grass and other weeds Im planting both together I will mow the buckwheat down and put in my compost pile how many years can I leave the clover there before I can till it under

Suzanne at Peaceful Valley Says:
Apr 9th, 2015 at 11:27 am

I am not sure the combination of buckwheat and red clover is a good one. Buckwheat enjoys warm temps and red clover is a cool season clover. If you want to put in a more perennial clover consider the Dutch or New Zealand clover. Not sure where you live but the red clover can be planted in fall or early spring and can be tilled in once hot weather hits.

Reply to this post

Your Name (required) Email, won't be published (required)


Please enter the word you see in the image below:

Find Solutions Books Fertilizers Garden Tools Growing Supplies Homestead Irrigation Seasonal Items Seeds Weed and Pest Control Other