Nitrate for the garden: application of different types, tips for use
We tell you about the different types of saltpeter. We give helpful advice on using various kinds of saltpeter fertilizers in the garden.
You can find fertilizers with the word “nitrate” in their name on sale. Gardeners, especially beginners, believe that this is the same product. In fact, this is not the case. There are several types of nitrate fertilizers. They differ significantly in composition and application. Let’s take a closer look at all the nuances of fertilizing a garden with nitrate.
All about nitrate fertilizers
When working with nitrates, including preparing the solution and disposing of the leftovers, you should wear protective clothing and a mask. Avoid contact with your skin and mucous membranes. If this happens, wash the affected areas and see a doctor. Nitrates are flammable and explosive. Follow safety rules. Please review the manufacturer’s instructions and recommendations for handling them.
Nitrate and its varieties
Nitrates are a large group of substances that contain nitric acid salts. Nitrate fertilizers also include them. These fertilizers belong to the nitrate group and always contain nitrogen. In addition to nitrogen, the fertilizer also contains other elements. Their names and quantities depend on the type of nitrate. There are more than a dozen such minerals in total. Four of them are most commonly used in agriculture: ammonium, calcium, potassium, and sodium. They differ in composition, principle of action, and area of application. Let’s take a closer look at each type of fertilizer.
Ammonium nitrate: what it is and how it is used in the garden
This fertilizer can be called ammonium nitrate, ammonium nitrate, or ammonium nitrate. It contains nitrogen in various forms: ammonium and nitrate. The product is used for basic applications, including foliar and root feeding, as a nitrogen source. This is one of the most essential elements for plants. It is part of chlorophyll; therefore, it participates in photosynthesis, i.e., the nutrition of plant organisms. Nitrogen is involved in the synthesis of plant protein, thereby stimulating the development and growth of vegetative mass.
Ammonium nitrate contains about 34% nitrogen. This is its main active ingredient. When used correctly, ammonium nitrate has the following effects on the garden.
- Accelerates the development and growth of crops.
- Accelerates the accumulation of green mass.
- Increases yield.
- Accelerates the onset of fruiting.
- Improves fruit quality by influencing protein production in fruits and root crops.
Ammonium nitrate is chemically neutral but physiologically acidic. This means that on soil mixtures with a neutral pH, it has a slight acidifying effect. Acidic soils can acidify even more. Therefore, it is recommended to use it in combination with a neutralizing additive, such as chalk. On acidic soil mixtures, it is best to apply calcium ammonium nitrate or chalk, etc.
Chalk should be used as a neutralizer. The application of lime displaces ammonium as ammonia, causing an odor and a risk of poisoning.
Ammonium nitrate | Pixabay
This is a broad-spectrum fertilizer. Let’s list what can be fed with ammonium nitrate in the vegetable garden, on the plot, and in the garden.
- Fruit trees, stone fruits, and pome fruits.
- Berry bushes.
- Cereals and grasses.
- All vegetables.
Ammonium nitrate is best applied in spring, when plants start to grow and need to gain vegetative mass. In summer, it can only be used in the first few months, after which its application is highly undesirable. This is due to the high nitrogen levels, which affect the growth of foliage and shoots. During the fruiting period, it is unpleasant to accumulate green mass. Then the plant will devote all its energy to leaf growth, reducing fruiting. Winter crops should be fully mature by autumn, and young twigs should fully lignify to prepare for winter. The growth of new shoots or active foliage development during this period is also undesirable. This interferes with winter preparation and jeopardizes survival during winter.
The main way to use ammonium nitrate in the garden in the spring is to apply it when digging. Dry granules are evenly scattered over the surface, and then the soil is dug up to embed the fertilizer. After digging and forming the beds, it is advisable to water the ground so that the granules begin to dissolve. It is possible to apply dry under bushes, trees, etc. The granules are spread in a moistened tree circle, the soil mixture is loosened, and the preparation is worked in. You can prepare a liquid fertilizer for watering or a stock solution for application in a drip irrigation system. In any case, the dosage is selected exactly according to the manufacturer’s instructions.
Ammonium nitrate | ShutterStock
Sodium
Synonyms: sodium nitrate, natron, or Chilean saltpetre. It contains 15-16% nitrogen and 26-28% sodium. The fertilizer is water-soluble and used for basic application, foliar feeding, and root feeding. Sodium supports the process of photosynthesis, is part of the sodium-potassium pump, and is responsible for the delivery of carbohydrates in plant cells. It is especially necessary for so-called “sodium-loving” plants, which include root crops and tubers.
Sodium nitrate is an alkaline fertilizer. It effectively neutralizes acidic soils such as peaty, soddy, or podzolic soils. It cannot be used on carbonate, saline, or saline-alkali soil mixtures. It cannot be used together with urea, potassium carbonate, superphosphate, or ammonium sulfate.
Let’s list the crops that benefit from sodium nitrate fertilization.
- Fruit trees, stone fruits, and pome fruits.
- Berry bushes.
- Green crops: spinach, lettuce, celery, rhubarb, etc.
- Root crops: sugar beets, table beets, carrots, etc.
- Solanaceous crops: eggplants, tomatoes, peppers, potatoes.
- Ornamental and flowering crops.
Sodium nitrate is applied in spring and summer; autumn application is not recommended. The main application is during spring digging. The granules are spread out and then mixed into the soil. It can be used as a dry or liquid fertilizer, applied to the roots or leaves.
Important: Excess fertilizer makes the fruits dangerous to humans. Therefore, use the product strictly according to the manufacturer’s instructions on the packaging.
Sodium | ShutterStock
Potassium
This fertilizer has several names: potassium nitrate, Indian, or potassium saltpetre. It is the potassium salt of nitric acid. It contains about 13-14% nitrogen and up to 45-46% potassium. The latter is necessary for plants to normalize metabolic processes. It participates in photosynthesis and carbon fixation, which are essential for the accumulation of starch, sugar, and pectin in fruits. This improves their taste. In addition, potassium regulates plant development, strengthens its immunity, and increases frost resistance.
Let’s list the effects of potassium nitrate when used correctly.
- Strengthens the roots of vegetable seedlings and adult plants.
- Increases yield.
- Accelerates fruiting.
- Improves the taste of fruits.
The fertilizer can be used for vegetables, all fruit and berry crops, and ornamental and flowering crops.
Important. It is not recommended to apply the product to potatoes, greens, cabbage, or radishes. It is best to apply the fertilizer after ovary formation, i.e., in the summer. It is used for foliar and root feeding. Mixing with organic matter is prohibited. The product is neutral and can be used on all types of soil mixtures. It is perfect for peaty soil mixtures and loams.
Potassium | ShutterStock
Calcium
Synonymous names: calcium nitrate, nitric acid calcium. Nitrate fertilizer contains up to 15% nitrogen and up to 27% calcium. The preparation includes nitrate nitrogen, which plants can readily absorb. Calcium is in a completely soluble form, which is very rare. It helps crops absorb nitrogen, so these elements are almost entirely absorbed. Proper use of calcium nitrate gives the following results.
- Enriches the soil with calcium in a form that is accessible to plants, allowing them to absorb nitrogen fully and quickly gain vegetative mass.
- Stimulation of seed and tuber germination, activation of the growth of sprouted seedlings, and strengthening of their root system.
- Prevention of putrefactive and fungal diseases, such as top rot.
- Increased crop immunity, increased frost resistance of wintering perennials.
- Improvement in the quantity, quality, and taste of fruits.
The product is a physiologically alkaline fertilizer and does not acidify the soil. Calcium nitrate fertilizer is particularly effective for acidic soil mixtures in vegetable gardens. The alkaline complex not only fertilizes them, but also deacidifies them. It is permitted for use on all types of soil. Calcium nitrate is helpful for most vegetable, fruit, and ornamental crops. All nightshades are particularly in need of it. The product is applied in the spring before planting. It is rarely used during the growing season. The exception is the prevention and treatment of top rot and other types of rot.
How to use ammonium, calcium, and other nitrates correctly in the garden
The rules for using all types of nitrates are similar.
- Fertilizer dosage — strictly according to the instructions provided by the manufacturer on the product packaging.
- Follow the manufacturer’s recommendations for applying the product precisely. Root feeding should be done only in moist soil. When watering, do not allow the water to run onto the leaves or stems, as this can cause burns.
- After opening the package, transfer the granules to a tightly sealed container. Do not allow moisture or direct sunlight to come into contact with the product.
- Nitrates are explosive. They must not be heated or stored near heating appliances or flammable materials, such as straw, kerosene, sawdust, or alcohol.
- When preparing the working solution, do not smoke or stand near open flames, etc.
- It is prohibited to use kitchen utensils to dilute the preparation.
- Nitrates must not be used together with other preparations, for example, in a tank mixture. This is especially true for organic substances. Such “cocktails” can seriously harm plants.
❓ Questions and answers
When should I apply nitrate fertilizers?
Apply nitrate fertilizers when plants are actively growing and need nitrogen for leaf and stem development. Spring is usually ideal — especially before heavy leafy growth — and avoid excessive nitrogen later in the season when plants are setting fruit to prevent unwanted leafy growth.
How do I use these fertilizers safely?
Always follow the product instructions. Nitrates are powerful and can be harmful if misused. Wear protective clothing when handling, avoid contact with skin, and store them properly — keep them away from heat or combustible materials.
Can nitrate fertilizers harm the environment?
Yes. Over-application or applying near water sources can lead to nitrate leaching, which may contaminate groundwater or surface water. Use split applications, keep fertilizer out of runoff paths, and incorporate it into the soil to minimize environmental impact.
How can I tell if my plants need nitrate fertilizer?
Look for signs of nitrogen deficiency, such as pale or yellowing older leaves and slow growth. If plants show these symptoms, a balanced nitrate fertilizer can help — but adjust rates based on soil fertility and plant needs to avoid overfertilizing.
Hi, I’m Ben Carter!
I’m a certified organic vegetable specialist with over 12 years of experience. I grew up on a farm in Iowa and have helped hundreds of gardeners grow bountiful harvests without unnecessary chemicals. On this site, I share my proven methods. If you have any questions, leave them in the comments!
