What is the best fertilizer for a vegetable garden? It is a complicated question because the answer depends on the range of parameters, including what vegetables you grow, what soil is in your garden, how big your yard is, and much more. Let’s dig deeper to understand what vegetable garden fertilizer to use.
Vegetable Fertilizer: Top 5 Products
| Parameter | Miracle-Gro | Old Farmer’s Almanac | Miracle-Gro Liquid | Dr. Earth | Osmocote |
| N-P2O5-K2O | 24-8-16 | 8-4-8 | 12-4-8 | 4-6-3 | 14-14-14 |
| Available sizes | 3 oz., 5.5 lbs. & 10 lbs. | 2.25 lbs. | 1 lbs., 4.5 lbs. & 8 lbs. | 4 lbs. | 1 lbs., 2 lbs. & 8 lbs |
| Naturality | Synthetic | Organic | Synthetic | Organic | Synthetic |
| Coverage (per lbs.) | 400 sq.ft. | 111 sq.ft. | 32 sq.ft. | 12 sq.ft. | 40 sq.ft. |
| Frequency of use | Every 1-2 weeks | Every 6-8 weeks | Every 3 months | Every 1-2 months | Every 4 months |
Miracle-Gro – Best Fertilizer for Vegetables
This all-purpose organic fertilizer is used for a variety of plants, including flowers, vegetables, shrubs, and trees. It is safe for plants, even if it is used directly. Being a synthetic fertilizer, it has an indefinite shelf life.
Miracle-Gro offers the broadest range of packaging, from 3 oz. to 10 lbs. However, the unique packaging is a plastic bag with 24 sticks. This new format is exceptionally convenient for use as all the fertilizer dosages are already pre-packed.
For more convenient use of Miracle-Gro fertilizer, use its branded feeder. It is refillable and makes mixing for you.
Miracle-Gro is super-rich on nitrogen. Every 100 pounds of fertilizer contain 24 pounds of nitrogen. As nitrogen is the most crucial element of fertilizer contributing the plant growth, Miracle-Pro is highly effective on the growing stage. However, as this fertilizer contains much nitrogen, it requires some soil analysis before using it. If your soil contains too much salt, the intensive use of nitrogen can increase the level of salt even more. Besides, nitrogen overdose can lead to growing leaves and roots at the expense of flowers and fruit. The first sign of extra nitrogen usage is the yellowing of leaves and the absence of fruit.
The significant nitrogen consumers are roses, corn, lettuce, tomatoes, squash, cucumbers, and cabbage.
Apart from being highly nitrogen-containing, Miracle-Gro has the most content of potassium that is needed for plant growth and reproduction. The sign of potassium deficiency is when the lower leaves start yellowing. Usually, it reflects the leaf edge, although even the entire leave can be hurt. The reason behind this is that potassium negatively affects nitrogen. So, by adding high levels of both nitrogen and potassium, Miracle-Pro compensates the disadvantages of both.
When it comes to disadvantages, it’s necessary to say that Miracle-Gro can’t be used for feeding plants marked as ‘organic’.
One pound of the fertilizer is enough for 400 sq.ft, which is highly cost-efficient.
Pros
- The most nitrogen-containing fertilizer
- Has the most comprehensive packaging range
- Organic
- Cost-efficient
Cons
- Synthetic
- Requires soil-analysis to keep from overdosing with both nitrogen and potassium
Old Farmer’s Almanac – Best Organic Fertilizer for Vegetable Garden
This is an entirely organic OMRI-listed fertilizer. This fertilizer perfectly fits to grow any vegetables in any geographic area. Feel free to use it for vegetables and fruit, herbs and trees, and even shrubs. The fertilizer is odor-free.
This is an entirely organic OMRI-listed fertilizer. This fertilizer perfectly fits to grow any vegetables in any geographic area. Feel free to use it for vegetables and fruit, herbs and trees, and even shrubs. The fertilizer is odor-free.
It is highly cost-effective because it can be used only in or around your plants.
The fertilizer contains 8% nitrogen, so it is an excellent choice for those supporting their plants, not for those requiring significant improvement in nitrogen content.
Pros
- Purely organic
- Ideal on the supporting stage
- Fits for both indoor and outdoor gardening
Cons
- The content of nitrogen cannot be enough for soils with low nitrogen.
Miracle-Gro Liquid – Best Liquid Fertilizer for Vegetable Garden
Miracle-Gro Liquid is similar to Miracle-Gro, but it is in liquid form and contains twice less volume of useful nutrients as compared to Miracle-Gro.
When it comes to fertilizer consumption, the maximum square that can be fed by liquid Miracle-Gro is much lower than that of a solid format (one pound can feed only 32 sq.m of the garden). On the other hand, liquid fertilizer requires feeding every three months instead of every 1-2 weeks needed for the solid format, which makes it cost-efficient.
Pros
- Rich for nitrogen, potassium, and phosphorus
- Ideal for those who don’t need much time for plant feeding
- The format is convenient to use
Cons
- Has lower coverage than its solid analog
- Earth – Best Fertilizer for Tomatoes
Dr. Earth – Best Fertilizer for Tomatoes
It is 100% natural and organic OMRI certified non-GMO verified fertilizer that can be considered a fish fertilizer for vegetables. Being the best fertilizer for tomato plants, it remains the best natural fertilizer for vegetable gardens, winter and summer crops, and container plantings.
What is inside? The basis is feed grade and human ingredients, including fish, kelp, feather, and alfalfa meal. Besides, proteins, multi-minerals, carbohydrates, and trace elements are added. When it comes to humic acids, their content is as much as 6%.
1 lb of this fertilizer is enough for 12 sq.ft., which is not too much. However, as it’s enough to feed plants with Dr. Earth as rarely as every 1-2 months, it remains relatively cost-efficient.
Dr. Earth’s plastic pouch has a convenient zip-press closure that is exceptionally convenient in use.
As one of the bag’s ingredients is a fish meal, this fertilizer has a bit of fishy smell mixed with an earthy smell.
Pros
- OMRI certified
- Non-GMO verified
- Convenient in use packaging
Cons
- A low number of available sizes
- A low coverage square
- Smells
Osmocote – Best Fertilizer for Gardens
Osmocote has the highest content of phosphorus among all the fertilizers listed, 14%. This element is needed to convert the sun’s energy into plant compounds. Phosphorus makes plants disease resistant, stimulates root development, flower formation, and seed production.
Since it is by far challenging to diagnose the lack of phosphorus, often, it becomes too late to correct its content. The first symptom when phosphorus is required is discoloration of leaves. When it comes to the potential overdose with phosphorus, it’s impossible, which makes Osmocote the ideal fertilizer to prevent the phosphorus deficiency.
Since it is slow-release resin-coated, the fertilizer feeds plants up to four months, which is the longest time among the listed fertilizers.
First of all, Osmocote fits seasonal vegetables and perennials. It gives plants an early-season start.
The major disadvantage of this fertilizer is that this is synthetic and can’t be used for plants marked organic. Moreover, recently formula for the product changed, and instead of balls of fertilizer coated with a shell, there are white fertilizer-covered balls. When fertilizer soars, it takes time for these white balls to release.
This solid fertilizer is available in three sizes.
Pros
- One feed lasts four months
- Has the highest content of phosphorus
Cons
- Doesn’t fit organic plants
Buyer’s Guide
What Does 10 10 10 Mean (N-P-K)?
The first number states for the percentage of nitrogen contained in the fertilizer. The second number indicates how much phosphorus is inside. And the last figure shows the amount of potassium in a pack.
It means that 100 lbs of 10-5-7 fertilizer contain 10 lbs of nitrogen, 5 lbs of phosphorus, and 7 lbs of potassium.
Let’s dig deeper to understand when a gardener needs these elements?
Nitrogen is needed to improve plant growth and crop yield. You can see the lack of this element by looking at the plant leaves. First of all, older leaves suffer first. If you see that leaves of your plant turn to yellow or purple and red spots appear, it is likely that your plant needs to be fed with nitrogen. The overuse of the element can cause the plant’s excessive growth at the expense of fruit and flowers—more information about the influence of nitrogen on the plant you can find in the research.
Phosphorus takes part in photosynthesis and cell division. The first symptom of the lack of phosphorus is when older plant leaves become blue-green, reddish, or purple. Sometimes, a plant can even lose its leaves. By itself, the overuse of phosphorus isn’t toxic for a plant. However, it can result in the decline of zinc and iron. It means that excessive consumption of phosphorus looks the same as zinc and iron deficiency. If you water your garden with greywater, ensure that your fertilizer doesn’t contain too much phosphorus or, even better, whether it’s phosphorus-free.
When it comes to potassium, it is required by plants in big doses for reproduction functionality and growth. You can detect that your plants feel like potassium level isn’t enough when spots on the leaves appear or leave color changes starting for the leave margins. Although it is quite rare to see the overdose with potassium, this element can impede the uptake of such elements as magnesium, iron, and zinc.
Test Your Soil to Choose the Best Fertilizer for Garden
Best garden fertilizer is a vague term because it differs significantly from the soil and a plant you feed.
To choose the best fertilizer for gardens, we recommend you start with the soil test. The annual pH test is required for soils where gardeners grow the same plants from year to year. For sandy soils, we recommend you to test the salt level every 4-5 years. For those starting a new garden or having any problems with the garden previously, we’d advise making a general test for all the elements, including nitrogen, potassium, phosphorus, and other items. In general, it’s good to make the soil test not less than once every two years. The cost of such a test can be less than $25, so it shouldn’t be neglected.
Here is a table of the desired test level according to the research made by the University of Illinois.
| Element | Desired Level of the Test |
| Phosphorus | 75 lbs / acre |
| Potassium | 400 lbs / acre |
| Calcium | 1,000 lbs / acre |
| Magnesium | 250 lbs / acre |
| pH | 6.0 to 6.8 |
Best Fertilizer for Plants Depending on the Growth Stage
Although there are fertilizers that can be used during the entire gardening season, it’s better to differentiate them depending on the vegetable growth stage.
In the first two weeks, transplanted plants require extra feeding that will stimulate their growth. For this, use a fertilizer that is rich in phosphorus. The only thing we’d like you to pay attention to is don’t overuse your fertilizer and stick to recommendations on the packaging.
When your plant appeared above the soil, you can feed it with a high nitrogen fertilizer for vegetables.
How to Choose a Nitrogen Fertilizer for Vegetables?
Many lawn fertilizers are rich in nitrogen. However, we don’t recommend you use it for your vegetable garden. This is because nitrogen stimulates leaves and stems growth at the expense of fruit and flowers. Besides, extra usage of nitrogen can lead to insect and disease problems.
That is why choosing a nitrogen fertilizer, pay attention to those products developed especially for vegetable gardens.
Seasonality of Fertilizing
As fertilizers enhance soil and led to abundant yield, it is essential to use an excellent compost for the vegetable garden. The feed season starts in winter when crops are removed, and the soil is still soft. At this stage, you can use the balanced fertilizer with a high amount of nitrogen, phosphorus, and potassium.
Then, in spring, you need to add fertilizer while planting. On this stage, it’s better to fertilize, not the entire garden, but use fertilizer only in or around the hole where you put your plant. After feeding, don’t forget to water your plants intensively.
When you use fertilizers in summer, grasp your attention on the following domains:
- Instructions how often to use your fertilizer, which is stated on the pack
- What kind of vegetable/fruit/grass you fertilize (e.g., tomatoes are heavy nitrogen feeders)
- Check up the current state of your plant to detect deficiency or overdose with any elements promptly.
In the fall, fertilizers are required only for plants with autumn fruit. You can use a slow-release fertilizer to boost your production; however, stop feeding plants after the first frost. This is because frost makes stress for a plant. On top of such conditions, the growth boost caused by even the best plant fertilizers uptakes the plant stress level, leading to plant death.
What Does OMRI Certification Mean?
Some fertilizers state that they are OMRI (Organic Materials Review Institute) certified. The Institute certifies only those crops that were planted without any synthetic feeders. So, if you’d like to get this type of certification for your product, pay attention to fertilizers you use for your vegetable garden.