How To Add Nitrogen To Soil

By Jason Jackson •  6 min read

If you’ve ever thought your garden was looking worse for wear, or noticed that your plants have started looking yellow, your problem may lie within the soil you use.

Soil needs enough nitrogen to support plant growth. Plants that grow from nitrogen-deficient soil may grow poorly or start showing yellow leaves.

This is clearly an issue, but to fix it, how do you add nitrogen to soil?

We’ll cover how to do so in this article. Keep reading to find out how to keep your soil nitrogen abundant and healthy.

Why Plants Require Nitrogen

Plants need nitrogen to create proteins, amino acids, and DNA.

When soil doesn’t have enough nitrogen, plants can’t make cells, so they cease growing.

Nitrogen is all around us, making up 78% of our air. However, plants can only take in nitrogen that’s converted to nitrates within soil.

This can occur through composting plants or manure, but it can also happen through nitrogen fixation.

How To Test Nitrogen Levels In Soil

Unfortunately, you cannot simply test soil for nitrogen through DIY methods. You’ll have to purchase a testing kit or have your soil professionally tested.

Some areas have extension offices that can test your soil for a low price. If you go through this route, the office may also tell you if your soil is low in any other important minerals.

You can also test your soil with suitable kits. These are generally available at garden centers and hardware stores.

These kits are normally simple to use and can give you a rough idea of how much nitrogen is in your soil.

How To Fix Nitrogen Deficient Soil

You can add nitrogen to the soil by non-organic or organic means.

Non-organic methods involve using chemicals. Organic ways don’t use chemicals, but they take more time to amend the soil.

Organic Methods

Here are a few organic ways to add nitrogen to your soil.

Manure

Animal manure can be an effective way to give your soil more nitrogen. Simply collect manure in a bucket and top it up with water.

Make sure that you don’t use manure from pets, like cats or dogs.

After you’ve made the solution, you can add more water to make it less concentrated. Applying this mixture to your soil is a quick and easy way of replenishing your garden with nitrogen.

As a bonus, any vegetables within will take up some nitrogen too.

Use Compost

Manure is a fast method of supplying nitrogen, but you should attempt to make your soil more fertile over time. You can do this with compost.

As you apply compost on your plant beds, nutrients will start spreading from the compost to your other plants.

One of these nutrients is nitrogen. As long as you focus on the long-term goal, it should reduce the likelihood of you needing to fix your soil quickly.

Once you leave the compost to work on your garden, the number of nutrients will grow along with it. Wait for it to decompose fully, then your soil should be well-nourished and full of nitrogen.

If you want to make your own compost, consider doing so with wood chips. They will act as mulch, which can add further nutrients to your patch.

The mulch also has other benefits, such as keeping your soil moist, deterring pests, and hindering weed growth.

Chop-And-Drop

Compost will keep your soil full of nitrogen, but it takes a lot of time to make. You can mimic the effects of compost through a similar method called chop-and-drop.

This involves cutting up any dying greens, like vegetables, then letting them fall onto the soil.

You can also try cutting any plant material from other places and applying them to your soil. The material will release important nutrients as it decays, nourishing the surrounding soil in the process.

Keep in note that while chop-and-drop mulch is effective, it isn’t a quick method.

Before the disintegrating plant material adds nutrients to the soil, a significant amount of nitrogen released escapes into the air.

Making compost is slightly faster, but the process will need more effort on your part.

Grow Nitrogen-Fixing Plants

Growing nitrogen-fixing plants, like beans and peas, can help address nitrogen issues. This is a complex method, but it can have fruitful results.

Traditional vegetables can supply the soil with nitrogen, but they will take up the same soil to create seeds that you will gather later.

The soil will absorb some nitrogen, but you must remove these plants for chop-and-drop before they start flowering.

This isn’t the best choice if you live on your home-grown vegetables, but you can still use this method by planting cover crops.

Before they are fully grown, cover crops are killed before they start absorbing nitrogen. Some implement this by planting them before cold weather hits.

The frost does the work for you, as it kills them before they mature fully. Another way of doing this is simply removing any plants that have just begun flowering.

Some gardeners regularly till cover crops in their soil, but this may cause more trouble later. This involves turning over the top layers of soil before planting new crops.

Tilling soil, even when done intermittently, can make the soil lose its nutrients. It may also cause a hardpan layer to form underneath the affected soil.

Growing the cover crop may make you lose more nitrogen than you wanted to achieve.

Non-Organic Methods

AIf you’re thinking of using chemicals on your soil, you can easily find products that contain nitrogen.

If you only need to add nitrogen to your soil, look at the NPK ratio, then choose a product that has a higher first number.

The ratio should be expressed in three numbers, for example, 10-10-10. The starting number will tell you how much nitrogen is in the fertilizer.

Chemical fertilizers have an advantage as they fix nutrient deficiencies easily. However, they won’t keep the soil nourished, as the nutrient concentration will start leveling out soon after application.

In the case of nitrogen, chemical fertilizers will supply your soil with a large amount of the element, but these nitrogen levels will start to wear off along with the fertilizer.