Garden Soil Inoculant: What It Is and Why You Need It
About 78% of our atmosphere is made up of nitrogen. It’s in the air we breathe and is necessary for plants (and humans) to survive. So how do you help your plants get all the nitrogen they need to thrive? The answer is garden soil inoculant. By inoculating your legume plants, you help to add nitrogen to your soil, which in turn lets the rest of your garden get the nitrogen it needs.
Nitrogen is a gas that occurs naturally in our atmosphere. It’s one of the big three nutrients that plants need to survive, the others being phosphorus and potassium. Plants need nitrogen to grow because it helps them perform photosynthesis, which is the process that gives the plant its food – and in turn, our food.
Plants can’t absorb nitrogen from the air; they need it to be in the soil to access it. That’s where inoculation comes in. Inoculation helps certain plants, namely legumes, to fix nitrogen in the ground where it can be accessed more readily.
I will admit to taking my peas and beans for granted. I put the seeds in the ground, and a short while later I’m enjoying delicious legume-based meals. After harvesting, I put the plants in the compost pile to start the process over again next year. I didn’t realize that I was missing an important step by leaving out a garden inoculant. If you aren’t using an inoculant, you’re not doing everything you can to make your plants happy.
This article will cover the basics of why and how you should inoculate your legume crops. You’ll also learn some fun, inexpensive ways to make your own inoculant.
What is an Inoculant?
There are many types of inoculants. A garden inoculant is anything that adds beneficial microbes to the soil.
Some inoculants are made of bacteria. You’ve probably heard of these beneficial bacteria in yogurt. In this article, we’ll focus on inoculating legume plants with , a bacteria which fixes nitrogen into the soil.
bacteria are microscopic beneficial organisms that live in the ground. They attach themselves to the roots of bean and pea plants. The plants then develop nodules which house the bacteria. These nodules help feed the plant and other surrounding plants.
Basically, these bacteria form a symbiotic relationship with legume plants that helps the beans and peas get additional nutrients. The bacteria don’t only benefit legumes, because anything you plant near or after your inoculated plants will benefit, too.
What Does It Mean To “Fix” Nitrogen?
When it comes to getting nitrogen from the air to the soil, some plants have special superman powers. These nitrogen-fixing plants use the bacteria to take nitrogen gas from the air and put it in their roots.
In particular, plants like legumes such as peas and beans are particularly adept at fixing nitrogen into the soil. That means they leave nitrogen in their roots behind in the ground. Most plants only uptake nutrients, but legumes kindly leave something behind.
This has an immediate benefit to the plants that are growing, but best of all, it helps nourish the next crop planted in the same location.
Using Garden Soil Inoculant
Ready to get going? Here’s how to make the most of garden soil inoculant.
You can purchase soil inoculates from garden centers or your favorite online store. Johnny’s Seeds offers several varieties. Commercial inoculants are made of bacteria, which multiplies once it is added to the soil.
A little inoculate goes a long way. According to Johnny’s Seeds, five ounces will cover one hundred pounds of seed.
Watch the expiration date on the package. Old bacteria will not grow well. Store extra inoculant in a cool, dry location.
Prepping the Seeds
Moisten seeds in non-chlorinated water before planting. If you’re using treated tap water, let it sit out for 24 hours prior to use. This will allow the chlorine to evaporate.
Plant your seeds as you would normally, but add some inoculant to each hole as you are planting. You cannot over inoculate your seeds. In this case, too much is better than too little. Not enough inoculant can result in poor bacteria growth.
One way to add inoculant is to place your seeds in a bowl and add a heaping teaspoon of the inoculant. Stir these two together. Next, add enough water to cover your seeds. Let the mixture soak together for an hour.
Then, plant your seeds. If you have some unabsorbed water with bacteria in it, pour that mixture into the planting hole with your seeds.
Planting Your Legumes and Bacteria
You don’t have to plant your peas and beans in any particular way to inoculate them. The bacteria like the same growing conditions as your plants. The soil should be between 55-80°F. Peas like the cool end and beans the warmer end of the spectrum.
Inoculant bacterium thrives in healthy, organic soil. Chemicals in the soil disrupt its growth. You want to work with nature, not against it, so don’t use pesticides or chemical fertilizers when inoculating your plants.
Inoculant prefers soil with a neutral pH, so add a little wood ash to raise your soil’s pH if necessary.
Making your Own Inoculant
You don’t have to buy inoculant. Your garden or nearby wilderness area has many types of bacteria that you can utilize. Growing bacteria is a bit more difficult and takes some laboratory equipment. However, you can always make your own starter with different bacteria using things you can find in your area.
Go out into a livestock field or meadow and pull up a legume plant such as clover. If the clover has nodes on the roots you can transport that to your garden to add beneficial bacteria. Make sure you are pulling from a sustainable field that hasn’t been treated with pesticides.
The following is a video for making another type of garden bacteria.