Vegetable gardens, especially summer vegetables, should be fertilized regularly for a healthy yield throughout the growing season. To determine what type or quantity of fertilizer is best for your veggies, you can perform a soil test.
It provides you with a better idea of what additional nutrients should be supplemented to your garden soil and will provide you with the exact levels of nutrients in the soil.
Continue reading to learn why fertilizers are necessary for your vegetables and what the best fertilizers for vegetables are.
NatureHills Nursery offers a wide range of vegetable fertilizers.
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Nutrients for Vegetables
The fertilizer needs of your vegetables vary based on the growth stage of the vegetables. For example, if a certain fertilizer is beneficial in the initial seedling growth stage, it might not be enough in the fruiting or flowering stage.
Certain vegetables like tomatoes benefit from an all-purpose fertilizer in the initial stage, but it needs a phosphorus-based fertilizer once they start flowering. Read more about the best fertilizers for tomatoes.
With potatoes on the other hand you need to differentiate between early growing potatoes and main crop potatoes when thinking about fertilizing, Rad more about the best fertilizers for potatoes.
Plants absorb the three basic elements carbon, hydrogen, and oxygen from water and air. But they also require additional macro and micronutrients for healthy growth.
Micronutrients should be present in traced amounts, whereas macronutrients should be in larger quantities (at least 0.1%).
As the soil ages, these elements can deplete and impact the growth of your vegetables. Therefore, you have to rely on fertilizers to ensure a steady supply of micro and macronutrients.
Read here about the best potting mix for vegetables.
Generally, leafy vegetables require a nitrogen-based fertilizer, whereas root or fruit vegetables need a phosphorus-based fertilizer.
The following are some of the common nutrients necessary for healthy vegetables:
Zinc – controls the growth hormones and helps in combining proteins.
Iron – is responsible for several reductions and oxidation reactions. It is also required for chlorophyll production.
Copper – supports respiration and photosynthesis and also helps in activating enzymes.
Manganese – it is necessary for respiration, photosynthesis, and nitrogen metabolism.
Phosphorus – it is necessary for nucleic acids and conversion of ADP to ATP. It also controls cell division, flower growth, and protein formation.
Nitrogen – is an essential element for all plants because it is found in proteins, amino acids, chlorophyll, and nucleic acids. It gives the plants the green color and is needed by all parts, including the roots, stems, and leaves.
Sulfur – it is important for the protein structure, biotin, and vitamins thiamine. It is also essential for the functioning of vitamin A which is needed for fatty acids metabolism and respiration.
Potassium – is a positive ion that develops the reproductive structure and balances the negative ions.
Magnesium – also balances the negative ions and is the main element in chlorophyll.
Calcium – is an essential part of the plant’s cell walls that impact its permeability. It provides structural support to the cell wall. It will also help activate certain enzymes.
Types of Fertilizers for Vegetables
Organic fertilizers are preferred by many gardeners, especially those who practice organic gardening for obvious reasons.
All the components of organic fertilizer are obtained from animals or plants. They are eco-friendly and cause no harm to the environment but ensure a steady supply of nutrients for your vegetables.
The most common type of organic fertilizer is manure. It is added to the soil or potting mixture before planting the veggies. The main disadvantage of manure is that your vegetables will require additional fertilizer during the growing season.
Compost is another alternative to manure, and it should also be added to the soil prior to planting.
Fish emulsion is also an organic fertilizer that is composed of parts of a fish or whole fish. It’s a great alternative to toxic chemical fertilizers.
It is mostly applied as a foliar feed because it’s rich in nitrogen and provides an NPK of 4-1-1. Remember that fish emulsion has low phosphorus content.
Fish emulsion is always applied after diluting it in water. Mix 1 teaspoon of fish emulsion with 1 gallon of water.
Spray this mixture directly on the foliage or pour it onto the base of the plant. Do not forget to water your vegetable plants thoroughly after fertilizing, to help them absorb the emulsion.
Repeat the application every 2-3 weeks or as required. You can buy a commercial fish emulsion or make a DIY version.
For a DIY fish fertilizer, mix 1 part of fresh fish, 1 bottle of unsulphured molasses, with 3 parts of sawdust to make your own homemade fish emulsion.
I do not prefer using commercial fish emulsion because it is not made of whole fish. Instead, they use trash fish parts.
So, the commercial varieties have less bone, proteins, and oils in them. They contain have lower quantities of microorganisms compared to homemade fish emulsion.
The next option for organic fertilization is manure tea. All the nutrients in manure can easily dissolve in water, and this mixture can be used in spray bottles or watering cans.
To make your own manure tea, mix 1 part of manure in 5 parts of water. I would recommend using cured manure because fresh manure is too strong for vegetables.
Always dilute the manure tea to avoid burning the vegetable roots or foliage.
For larger quantities, let the manure-filled tea bags sit in water for about one or two weeks. Strain the tea prior to use to separate the solids.
Most vegetables require the macronutrients readily available. Therefore, organic fertilizers are used in combination with other fertilizers.
Inorganic or Synthetic Fertilizers
Inorganic fertilizers are designed in two ways. They are either slow-release, meaning the nutrients are absorbed in a time period of several weeks or months.
The second option is where the nutrients can be absorbed by the plant instantly.
The number on the packaging of an inorganic fertilizer represents the nitrogen, phosphorus, and potassium quantity.
The first number is the percentage of nitrogen, and the next one is the percentage of phosphorus, followed by the percentage of potassium.
Most vegetables require a balanced fertilizer such as +61404532026 or +61404532026. But some of them will also need an additional supply of potassium. Leafy green vegetables need plenty of nitrogen.
These fertilizers usually have a higher nutrient content compared to organic fertilizer. They are available in liquid, granular, pellet, or powder form.
They are inexpensive compared to organic fertilizers but do not benefit the soil in the long term.
Best Fertilizers for Vegetables
I have compiled a detailed list of the best fertilizers based on my experience with vegetable gardening.
Fox Farm FX14049 Liquid Nutrient Trio Soil Formula
This trio by Fox Farm is designed to cover the fertilizer needs of your vegetables throughout the growth cycle. The Big Bloom liquid fertilizer contains earthworm castings and is perfect for the initial growth stage.
The Grow Big fertilizer promotes more growth to have more fruits and vegetables. It simply helps your plant get bigger and stronger.
Tiger Bloom is great for both soil and hydroponic gardening. You should start applying it once the plant starts flowering to have vigorous growth.
Burpee Organic Tomato and Vegetable Granular Plant Food
This fertilizer provides quick feeding to almost all types of herbs and vegetables. It contains all the necessary nutrients and beneficial microbes.
It also contains calcium and other minor micronutrients. The Organic Material Review Institute has listed it as safe for organic use.
These granules can ensure a steady supply of nutrients for your vegetables for up to 3 months. It can be used for both container gardening or established vegetable gardens.
Jobe’s Organics 09524 All Purpose Granular Fertilizer
This organic fertilizer is certified by OMRI and is suitable for vegetable gardening. It also contains Biozome, which is a healthy blend of proprietary microorganism archaea, fungi, and bacteria that can break down materials for rapid results.
The beneficial microorganisms in this fertilizer increase the root mass and improve the long-term soil quality.
It can help your vegetables resist drought, insects, and diseases. At the same time, it improves overall soil conditions.
This fertilizer should be applied at the time of planting or every 4-8 weeks. It is available in packaging of 1.5, 4 ad 16 pounds.
Worm Castings Organic Fertilizer
This fertilizer contains pure earthworm castings, making it suitable for several types of plants. You can use it for your vegetables or potted houseplants.
Earthworm castings provide instant nutrients and enrich your soil for a longer period of time. It is non-toxic and has no odor, so it is perfect for indoor vegetable containers.
In addition to nutrients, this fertilizer will also improve soil aeration and drainage.
Dr. Earth Premium Gold All Purpose Fertilizer
All-Purpose Vegetable fertilizers are designed to help the plant grow deeper roots, grow bigger in size, and produce more flowers/fruits.
This fertilizer has no synthetic chemicals making it an ideal choice for vegetables. It is enriched with proteins, multi-minerals, carbohydrates, humic acids, and other nutrients.
It is a great product for any stage of growth.
It is produced from Ascophyllum Nodosum and is one of the finest seaweed products available in the market. It improves root and seed development as well as increases the size of the flowers or fruits.
It helps your plant handle extreme weather conditions, diseases, and pest attacks. This natural product will not damage any of your plants or vegetables, so it can be used alone or paired with fish emulsion for better results.
Miracle-Gro Water Soluble Tomato Plant Food
Miracle-Gro is one of the well-known brands in the world of gardening. This particular plant food is suitable for all kinds of vegetables.
The NPK ratio for this one is +61404532026, making it perfect for container plants or seedlings.
You can apply it every 1 or 2 weeks using a watering can or the Miracle-Gro Garden Feeder. This product works instantly, but it is crucial to follow the instruction by the manufacturer to protect your vegetables from burning.
Osmocote Smart-Release Plant Food Flower & Vegetable
This is a perfect solution for vigorous growth and a robust root system. It has an NPK ratio of +61404532026, making it a complete fertilizer for your vegetable garden.
I would highly recommend it for seasonal vegetables. You should sprinkle and thoroughly mix the granules in the soil and water the soil to dissolve the granule coating.
This fertilizer should be reapplied after 4 months.
Espoma Organic All-Purpose Plant Tone Fertilizer
This all-purpose product is suitable for all your vegetables, flowers, and trees. It should be applied once a month in the growing season.
It can be used in the garden beds or for new or established potted plants. It contains nitrogen, potassium, phosphate, calcium, magnesium, sulfur, and other plant food ingredients.
Neptune’s Harvest Organic Hydrolyzed Fish & Seaweed Fertilizer
It has an NPK ratio of 2-3-1 and can be applied directly to the soil or foliage. It’s simple to mix and can be applied using a spray bottle, watering can, or at the drip line.
You should repeat the application every 2-3 weeks. It is made from a variety of fresh fish to ensure optimum nutrients for vegetables.
You should mix 1 ounce of fertilizer in 1 gallon of water to create a magical mixture for your vegetables.
Miracle-Gro Shake’ N Feed Tomato, Fruit and Vegetable Plant Food
This fertilizer enhances the long-term health of the plant by increasing water efficiency and developing strong roots. It has natural ingredients that are used by soil microbes for healthy growth.
A single application can last for 3 months. The calcium and micronutrient will increase the yield.
It can be applied to both container and in-ground vegetables by mixing it in the top 2-3 inches of the soil.
How to Fertilize Vegetables?
Knowing different methods of adding fertilizers is important because it impacts how your vegetables grow. But for this, you should also know the fertilizer needs of your individual vegetables.
Preplant broadcasting involves adding the fertilizers uniformly to the soil surface before planting. This method is great for adding micronutrients.
Side dressing is the most common method for crops or gardens that require frequent fertilization. In this method, you simply apply the fertilizer (mostly nitrogen-based) to both sides of the stems (about 4 inches away from the stems).
When the garden or crop is watered, the roots can easily absorb this fertilizer.
Side dressing is very useful in cases where continuous rainfall leaches the soil. In top dressing, you apply the fertilizer over the plant surface and soil.
For foliar application, the fertilizer is applied to the parts of the plant that are above the soil. The fertilizer will enter the plant cell through the stomata and cracks.
This gives a faster supply compared to soil application. Foliar application is useful for only a few plants because many plants have difficulty absorbing fertilizers via the leaves.
Fertilizing Vegetables Based on Soil
- If your vegetables are growing in clayey soil, they require less fertilization. Usually, applying once every 4-6 weeks is enough.
- For sandy soils, the vegetables need one or two applications every 3-4 weeks.
- Vegetables growing in organic soils need the lowest number of fertilizers. You should focus on the overall plant health and the color of the foliage to decide whether your vegetable needs any fertilizer or not.
- Vegetables growing in well-drained, porous soils require frequent fertilization. Use a balanced fertilizer every 3-4 weeks in the growing season.
Tips for Fertilizing Vegetables
- To apply micronutrients with an NPK fertilizer to seeds, apply them 4-6 inches away from the seeds to avoid damaging the seedling.
- Avoid high salt concentration in the soil as it impacts the water absorption capability of the plant.
- The rate of application varies depending on the brand or type of fertilizer. Therefore, I would highly recommend following the instructions on the label.
- Avoid direct contact of the roots system with the fertilizer because this can burn the roots. Watering your vegetable after fertilization will protect the roots from burning.
- Overfertilizing is more damaging than under fertilizing. Always apply according to the instructions by the manufacturer or less.
- Avoid fertilizing before a rainy day or when the weather is too hot.
- For granular fertilizers, always water the plant after application because these fertilizers only work after melting or dissolving.
- Store your fertilizers away from humidity and direct sunlight. You should keep them in a cool and dry location away from children or pets.
- Pay attention to the pH of the vegetable soil. They perform best with a pH between 6 and 7.
- Slow-release vegetable fertilizers are perfect to avoid burning your vegetables.
Frequently Asked Questions About the Best Fertilizers for Vegetables
How often should I test the soil to determine the nutrient content of my vegetable garden?
Get the soil tested every 2 years to ensure a steady supply of nutrients for your vegetables.
What is the best time for adding fertilizers to vegetables?
Most vegetables benefit from a fertilizer application once they are few inches tall or while transplanting. Depending on the vegetable you are cultivating, you might have to add supplement fertilizer later on for better growth and yield.
How should I fertilize the vegetables growing in containers?
Vegetables growing in containers, baskets, or hanging planters demand careful fertilization because they do not get natural soil nutrients. At the time of planting, add half a tablespoon of fertilizer to one gallon of potting soil. When the fruits or flowers start producing vegetables in the midseason, reapply a soluble fertilizer every 1 or 2 weeks.
I’m regularly feeding my vegetables with a nitrogen-based fertilizer, but the production has reduced; what is wrong?
You are most probably overfertilizing your vegetables. Be wary that excess nitrogen can reduce production and even impact the quality of the vegetables. The extra nitrogen can also increase pest and disease issues.
Why is it important to supply phosphorus to my vegetables only when necessary?
Because fertilizing with high phosphorus fertilizer at the wrong time can reduce the ability of the vegetables to absorb iron and other micronutrients.
Why are organic fertilizers great for vegetable gardening?
Organic fertilizers improve the soil structure, add organic matter and fight fungal or bacterial diseases; therefore, they are perfect for vegetable gardening.
Can I use lawn fertilizer for my vegetables?
Avoid using lawn fertilizers for your vegetables because these fertilizers have high nitrogen. They also contain weed control chemicals that can damage or kill your vegetables.
My vegetable plant has started yellowing, what is the issue?
One of the common reasons behind wilting or yellowing of vegetable plants is nitrogen deficiency. Apply a nitrogen-based fertilizer, and your plant will soon be healthy.
Do all vegetables need nitrogen-based fertilizers?
The nitrogen requirement can vary from one vegetable to another. For example, green vegetables like broccoli need plenty of nitrogen for healthy growth, but excess nitrogen can stunt the growth of a tomato plant. It is best to know the nutritional needs of your vegetables before fertilizing to avoid over or under-fertilizing.
Which season is the best for applying fertilizer to vegetables?
Spring is the ideal season for fertilizing any kind of vegetables, especially if the soil needs amendments or extra nutrients. But you might have to repeat application later in the growing season, depending on the plant.
All vegetables should be fertilized carefully for healthy produce. You should pay attention to what type of fertilizer is being used because the vegetables will be eventually consumed.
You can use any of the fertilizers recommended in this guide to growing delicious vegetables. Both organic and synthetic fertilizers are suitable for vegetable gardening.
I hope this guide shed some clarity on the different options available and will guide you in fertilizing your vegetables for the best results.
Marcel runs the place around here. He has a deep passion for houseplants & gardening and is constantly on the lookout for yet another special plant to add to his arsenal of houseplants, succulents & cacti.
Marcel is also the founder of Iseli International Commerce, a sole proprietorship company that publishes a variety of websites and online magazines.