Minor Biofumigation at the Fertile Garden

One of the benefits of growing Mustard Greens as a cover crop is its ability to clean the soil when tilled into the ground. When tilled into the soil, the plant material decays. As it does so, it releases volatile gasses containing chemical compounds that fumigate the soil. The term for this kind of cleaning of the soil by growing brassicas, mustard greens or radishes is called “biofumigation”.

 

 

 

 

 

 

 

 

 

An essential component of biofumigation is to cover the plot as soon as possible after incorporating the chopped up plants into the soil. Instead of saturating the surrounding soil, the volatile gasses will dissipate if not properly covered. While using plastic is generally preferred, I decided to do what I could with a layer of paper and soil. 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

After chopping up the plants, I covered the debris with packaging paper and a layer of a high-quality soil blend. I made sure to water it all in well. In the end, between the off-gassing and the paper, the end result did dramatically decrease the incidence of weeds in the garden this last spring.

Raising more than just Mustard Greens

I love supporting local wildlife with flowering plants. I also love seeing some insects on my plants. It lets me know that I the plants are healthy enough for other animals to consume. However, there comes a time when enough is enough.

 

 

 

 

 

 

 

 

 

 

 

 

That time came for me this last winter when my Mustard plants became the breeding ground for several dozen uninhibited harlequin bugs (not pictured). By the time I was able to get to the plot, the bugs had begun multiplying. In order to deter the adults to set up camp, I came back as soon as I could – at night – and chopped down all of the plants. This left a lot of residue, but given the proliferation of bugs and the potential for the Mustard to spread seed, it was wise for me to remove the plants as quickly as possible.

2023 Backyard Mustard Greens

This last winter I pretty impressed with how tall and lush the mustard greens in my garden grew. Especially considering that my garden has been suffering from the nearby trees and local fungi extracting the nutrients from the soil. Given how much it has been struggling in the summer, it was great to see it do so well over the winter.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

One nice thing about growing in your own backyard is that you can see when the flowers are blooming and cut them down long before their seedheads mature. Just by looking out my back window I could see how the plants were coming along and take care of them while they were still manageable.

Cover Crops in the Grape Harvest Bins

Every year I change what I am growing in my winter gardens. The majority of the time it is a cover crop. This last winter, I chose to grow out Mustard Greens. Mustard Greens are usually very good at cleaning the soil, though they don’t provide a lot of organic matter. At both of the gardens where I planted them, they grew a bit wispy. However, at the old chicken plot, they were a little more vigorous. Once I had taken the time to cut the plants down, I covered them with a high quality soil mix.

 

 

 

 

 

For the second garden, which had received a lot of city compost with excessive pathogenic bacteria, the results were nowhere near as good. The plants dithered and only grew a little. We tried planting buckwheat, but to no avail. So in the end, I planted some fava beans in some high quality compost. Those seemed to do very well and helped better prepare my garden for the summer crop

 

 

 

Favas above and Favas Below

There are a number of reasons why fava beans are of my very favorite crops to grow. First is that the seeds are very easy to handle. With seeds so large, they are very easy to sow and work with. The second reason is that the plants germinate relatively quickly. Within a week or two I can see the results of my planting. Third, they are relatively hardy. In northern California, they can grow primarily off of winter rains and tend to deal with pest pressure more than other cover crops. And my very favorite thing about fava beans as a cover crop is how much they improve the soil. Whether I only have a month or five months, the residue of fava beans works as fertilizer, as mulch and as compost. The fact that the beans can be consumed is just a bonus.

 

 

Here are some pictures of my “Robin Hood” Fava beans that I took in four gardens in the winter of 2022 to 2024.

 

 

 

 

 

The first pictures are of a garden that I started in a one yard grape bin at a friend’s house. This macro grape bin replaced a macro cubic yard bag full of high-quality compost. The majority of the growing medium in the bag was from compost.

 

 

 

This second group of pictures is from an above-ground garden that I established in 2020 using cinderblocks made for holding wood boards for a planter bed. They are both above-ground beds that I established in the front yard of a friend’s home.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

The third group of pictures is my own little backyard plot.

 

 

 

 

 

 

 

 

 

 

And finally, the last group of fava beans was grown at the friend’s garden that I call the “Fertile Garden” because it is just that. I would really have difficulty growing what I do without access to this garden plot. The final crop of Robin Hood Fava beans that I grew was harvested in late May and was the source of much of my future seed.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Whether grown in the ground or in an above-ground planter, fava beans are a fantastic crop to grow in cool weather. If you have never grown them before, I would highly recommend it!