This is the second part of a two part post series. In part 2: we’ll be covering the basics of cover crops and discussing when to plant, how to plant and mulch them, and where to buy.
Originally posted February 28, 2022
Modified March 5, 2024
Integrating cover crops into your raised bed gardening strategy can yield a multitude of benefits. These crops, which are grown not for harvest but rather to enhance the soil’s health, are an excellent way to improve fertility, manage weeds, and support beneficial soil biodiversity. Raised beds are particularly susceptible to nutrient depletion and soil compaction, which can be mitigated by the careful selection and management of the appropriate cover crops.
Choosing the right cover crops for your raised beds involves understanding the specific needs of your soil and the subsequent crops you plan to grow. Options include legumes like clover and vetch, which fix nitrogen in the soil, and grasses like rye or barley, known for their robust root systems that break up compacted soil. When managed correctly, these cover crops can be cut down and left on the beds to decompose, adding organic matter and nutrients back into the soil, preparing it for your next planting season.
Key Takeaways
- Cover crops enrich soil health and manage common raised bed issues.
- Selection of the correct cover crop depends on your soil’s specific needs.
- Proper management of cover crops contributes to improved soil fertility for future plantings.
This post is all about cover crops for raised beds.
Table of Contents
What Are Cover Crops?
Cover crops provide a way to reduce or completely eliminate the need to use synthetic fertilizers by adding organic material and minerals like nitrogen and phosphorus. They create a biodiverse environment for bacteria and fungi that attract beneficial insects, like earthworms. They’re a deterrence for weeds, pests, and diseases. You don’t need to have a big piece of land to benefit from cover crops either. You can use them in a small garden or even used them in raised beds.
In the past couple of years, I have experimented with cover crops in both our in ground garden and one of our raised beds. I was pleasantly surprised by how well they worked in spite of the research I’ve done on them. What I think would be a great experiment would be to keep records of each year through soil testing for comparison.
If you haven’t read the first part of this series, check it out here! In the first part, Learning the Basics About Cover Crops: What the Benefits are and How to Use them in the Garden, I discussed what I was experimenting with during the spring and fall of 2022, what cover crops are and how they can benefit your garden, what benefits they serve, and examples of what to use.
The second part of the series discusses when to plant cover crops, how to plant and mulch them, where to buy cover crops, and which ones you can also plant in the fall and winter.
[RELATED POST: Learning the Basics About Cover Crops: What the Benefits are and How to Use them in the Garden]
Benefits of Cover Crops in Raised Beds
Incorporating cover crops in your raised beds can lead to substantial improvements in soil health and garden vitality. Here’s how they can specifically benefit your gardening efforts.
Soil Fertility Enhancement
Cover crops are crucial for enriching soil fertility in raised beds. They add organic matter and increase nutrient availability when decomposed into the soil. For instance, leguminous cover crops like winter pea fix nitrogen, effectively improving soil nutrient content without the need for chemical fertilizers.
Pest and Disease Management
The strategic use of cover crops can help in disrupting the lifecycle of pests and diseases. Certain species provide habitat for beneficial insects that act as natural pest control. For example, flowering cover crops such as buckwheat attract pollinators and predatory insects, which may help manage pest populations.
Water Conservation
Cover crops play a vital role in conserving water. Their root systems create pathways that help water infiltrate the soil, reducing runoff. Additionally, their foliage helps to minimize evaporation from the soil surface, preserving moisture for your primary crops.
Weed Suppression
By establishing a cover crop, you can suppress weeds effectively. A dense planting of cover crops, like cereal rye, competes with weeds for space and resources, reducing your need to use herbicides or engage in labor-intensive weeding practices. This natural barrier against weeds means less work for you and more nutrients for your desired plants.
When to Plant Cover Crops
When to plant cover crops depends on the variety you’re looking to plant. Before buying seeds, check to see what crops are best suited for your plant hardiness zones, determine your frost dates, and figure out what your goals are for your soil. Plant in either late summer or early fall after you’ve planted.
How to Plant and Mulch Cover Crops
How to plant a cover crop and how and when to mulch it will also depend on the type you choose. According to Sustainable Agriculture Research and Education, there are three different ways cover crops are planted:
- Plant an entire cover crop for an entire growing season.
- Plant the cover crop after you’ve harvested your garden. This would be ideal so that you can replenish the soil and start prepping the soil for next year’s growing season. After all, it does take some time for the nutrients and minerals to work into the soil.
- Growing your vegetables and fruits with your cover crops, or interseeding.
Mulching cover crops should be done before they begin to flower. There are certain areas of our property though that I would like to keep the cover crops growing. This will allow an increase of pollinators as they bloom and grow alongside our herbs and flowers we have growing around the property.
There are a couple of ways to mulch cover crops. How you mulch depends on your preferences.
- Mow the cover crop. A quick and easy way to mulch the cover crop is by mowing it. Mowing will help speed up the process of breaking down/ compost the plant.
- Cut the plants by hand with scissors. Obviously this would not be recommended if you have a large garden. This is do-able in a small garden or raised beds.
- Tilling the cover crop into the soil.
What to Do Next After Cutting the Cover Crop
After cutting the cover crop, there are one of two things you can do next. The cover crop can be left to lay on the surface of soil like a mulch. By leaving the cover crop on top of the soil, it will protect it from washing away. A second option is to lightly mix/till the crop into the soil,
Where to Buy Cover Crops
There are a number of places where you can buy cover crops online. To my knowledge, at least from what I’ve seen in my area, big box stores don’t carry cover crops. I haven’t seen them sold at our local garden nursery either. That may differ in your area though. There are three different seed sellers that I normally buy from, but only two sell cover crops:
- Botanical Interests is a small company that sells 5 different varieties of cover crops – hairy vetch, common buckwheat, crimson clover, a combination of peas and oats, and fava beans.
- Johnny’s Seeds sells three different types of cover crops from small quantities (1 pound) up to larger quantities (50 pounds), depending on your needs and how much ground you need to cover. They sell a combination of peas and oats, a spring green manure mix (a mixture of field peas, oats, and hairy vetch), and a fall green manure mix (a mixture of winter rye, field peas, ryegrass, crimson clover, and hairy vetch).
A third seed company I would eventually like to try is Territorial Seed Company. There are 28 different varieties that they sell from alfalfa to mixes like Organic SummerMax mix which combines 40% Buckwheat, 40% Soybeans, and 20% Viking 220 Sorghum Sudangrass.
Winter Cover Crops
Cover crops can be planted in the fall and left to overwinter to improve soil conditions. These plants don’t only improve the soil conditions and fertility, but they also help with:
1. suppress cool season weeds
2. prevent soil erosion
3. helps prevent soil compaction – these plants help reduce soil compacting, especially for clay soils, and improve root, air, and water penetration.
4. overall help prepare for the spring and growing season.
There are a considerable amount of winter cover crops to choose from:
- crimson clover
- buckwheat
- radishes
- black eyed peas
- hairy vetch
- peas
- oats
- soybeans
What cover crops are you interested in trying in your garden this year?
This post was all about cover crops for raised beds.