How to Sow Green Manure: A Complete Guide for November Garden Prep

As the growing season comes to a close, November is an ideal time to sow green manure in your garden. Green manure is a cover crop that helps protect your soil over winter, improves soil structure, and adds valuable nutrients when it is turned back into the ground. By sowing green manure in November, you can prepare your garden for a more productive and fertile growing season in the spring. This guide will show you how to sow green manure, which crops to choose, and why it’s an essential part of winter garden maintenance.

Why Is Sowing Green Manure Important?

Sowing green manure helps maintain soil health during the winter months when your beds may otherwise be bare. Green manure plants provide several key benefits:

Prevents soil erosion: Green manure protects the soil from erosion caused by winter rain, wind, and frost.
Adds organic matter: As green manure crops decompose, they improve soil structure, increase fertility, and add organic matter to the soil.
Fixes nitrogen: Some types of green manure, such as legumes, fix nitrogen in the soil, which benefits future crops.
Suppresses weeds: By covering the soil, green manure suppresses weed growth, reducing the need for weeding in the spring.
Improves water retention: Green manure helps the soil retain moisture, preventing it from drying out during winter.

By sowing green manure in November, you’re actively working to enrich your garden’s soil and prepare it for the next growing season.

Best Green Manure Crops to Sow in November

Different types of green manure provide various benefits depending on your garden’s needs. Here are some of the most common green manure crops to sow in November:

1. Winter Rye

Winter rye is one of the most popular green manures for winter sowing. It’s fast-growing, cold-tolerant, and provides excellent weed suppression. Winter rye also has deep roots that help break up compacted soil and improve drainage.

Benefits: Soil erosion prevention, weed suppression, improves soil structure.
When to sow: Early to mid-November, before the ground freezes.

2. Field Beans

Field beans are legumes that fix nitrogen in the soil, making them a valuable crop for replenishing depleted nutrients. They’re cold-hardy and can survive winter temperatures, growing slowly until spring.

Benefits: Nitrogen fixation, soil improvement, adds organic matter.
When to sow: Mid-November, in areas that are not likely to experience harsh freezes.

3. Crimson Clover

Crimson clover is a nitrogen-fixing legume that grows quickly in cool temperatures. It works well as a winter cover crop and helps suppress weeds while enriching the soil with nitrogen.

Benefits: Nitrogen fixation, weed suppression, adds organic matter.
When to sow: Early November, as it needs time to establish before frost.

4. Winter Vetch

Winter vetch is another legume that fixes nitrogen and grows well in cool conditions. It’s often combined with other green manure crops like rye for a more balanced nutrient profile.

Benefits: Nitrogen fixation, improves soil fertility, prevents erosion.
When to sow: Early to mid-November.

5. Mustard

Mustard is a fast-growing green manure crop that helps suppress weeds and breaks down quickly in the soil, adding organic matter. It’s especially useful in controlling certain soil-borne pests and diseases.

Benefits: Weed suppression, soil conditioning, pest control.
When to sow: Early November, as mustard needs time to establish before frost.

How to Sow Green Manure in November

1. Prepare the Soil

Before sowing green manure, clear away any remaining plant debris from your beds. Remove weeds and lightly rake the surface of the soil to create a fine, even seedbed. You don’t need to dig the soil deeply—simply loosen the top layer enough to sow seeds evenly.

2. Choose Your Green Manure Crop

Select the best green manure crop based on your garden’s needs. Consider whether you want to fix nitrogen (legumes like clover or beans), improve soil structure (rye or vetch), or suppress weeds (mustard or rye).

3. Sow the Seeds

Broadcast the green manure seeds evenly over the prepared soil. For larger seeds like beans, you may need to rake them lightly into the soil to ensure good soil contact. For smaller seeds like clover or mustard, simply scatter them on the surface and water them in.

Seed depth: Most green manure seeds should be sown about 1/4 to 1/2 inch deep, depending on the type. For larger seeds like rye or beans, sow a bit deeper to ensure they are well-covered.
Seed spacing: Green manure crops should be sown densely to ensure full ground coverage and weed suppression. Follow the specific recommendations for each crop type.

4. Water the Seeds

After sowing, water the area thoroughly to help the seeds germinate. Ensure the soil remains moist, especially in dry conditions. While November can be rainy in many regions, you’ll want to monitor the moisture levels and water when necessary.

5. Monitor the Growth

Green manure crops will grow slowly during the winter months, but they’ll provide important soil protection throughout the season. In milder climates, some crops will continue to grow, while others may go dormant until early spring. Keep an eye on their progress and ensure they’re covering the soil adequately to prevent weeds and erosion.

6. Incorporate the Green Manure in Spring

Come spring, the green manure will be ready to be incorporated into the soil. About 2-4 weeks before planting your spring crops, cut down the green manure with a sharp spade or mower, and dig the plant material into the top layer of soil. This process adds organic matter and nutrients, enriching the soil for your next round of crops.

Allow the green manure to decompose before planting new vegetables, giving the soil time to absorb the nutrients.

Most Common Questions and Answers About Sowing Green Manure

Q1: When should I sow green manure?
A: Green manure should be sown in November, ideally before the first frost. This gives the plants time to establish roots before cold temperatures set in. Winter rye, clover, and field beans are great choices for winter sowing.

Q2: Can I sow green manure in raised beds?
A: Yes, green manure can be sown in raised beds just like in-ground gardens. It’s especially beneficial in raised beds, where soil can dry out or erode more quickly during the winter months. Choose a crop like rye or mustard for raised beds to protect the soil.

Q3: What are the benefits of sowing green manure?
A: Green manure prevents soil erosion, suppresses weeds, improves soil structure, adds organic matter, and fixes nitrogen in the soil. It also helps retain moisture in the soil and promotes healthier crops in the following growing season.

Q4: How do I incorporate green manure into the soil in spring?
A: In spring, about 2-4 weeks before planting your next crops, cut down the green manure plants and dig them into the soil. This process adds organic matter and nutrients to the soil as the plant material decomposes, improving soil fertility.

Q5: Can green manure crops survive frost?
A: Yes, many green manure crops are frost-hardy and can survive winter temperatures. Crops like winter rye, field beans, and vetch are specifically chosen for their ability to grow in cold conditions and protect the soil throughout winter.

Q6: How does green manure improve soil health?
A: Green manure improves soil health by adding organic matter, enhancing soil structure, and increasing nutrient availability. Leguminous green manures like clover and field beans also fix nitrogen in the soil, enriching it for future crops.

Q7: What happens if I don’t incorporate the green manure into the soil in spring?
A: If green manure is left to grow without being incorporated into the soil, it may become too woody and harder to break down. It’s important to cut it down and dig it in before it flowers or goes to seed, ensuring it decomposes properly and releases nutrients into the soil.

Q8: Can I sow green manure in small gardens?
A: Yes, green manure is suitable for gardens of all sizes. Even in small garden beds, sowing green manure helps maintain soil fertility and prevents weeds. Choose fast-growing crops like mustard or clover that fit well in smaller spaces.

Q9: Do I need to water green manure in winter?
A: Green manure typically doesn’t need much watering in winter, especially in rainy or snowy regions. However, if you’re in a dry area, it’s important to water the seeds after sowing to ensure germination. Keep an eye on soil moisture levels, particularly in raised beds or dry climates.

Q10: Can I plant vegetables immediately after turning in green manure?
A: It’s best to wait about 2-4 weeks after turning in green manure before planting new crops. This allows the organic matter to decompose and prevents nutrient competition between the green manure and your new plants.

By sowing green manure in November and following these tips, you can protect your soil throughout the winter, improve its fertility, and set the stage for a successful spring garden. Whether you’re looking to fix nitrogen, suppress weeds, or add organic matter, green manure is an essential part of winter garden maintenance.