Starter fertilizers are applied to fields and gardens to support plants through the process of transplantation and help them recover from transplant shock faster.
Starter fertilizer is worth it to ensure survival and early maturity in seedlings as they’re able to root faster and grow quicker into adult plants. When applied correctly, starter fertilizer can improve both the quality and quantity of yields from plants like fruits, vegetables, and crops.
In this article, I’ll explain what starter fertilizers are, what they’re made of, and how you can use them correctly to improve your garden, so read on!

All About Starter Fertilizer
Starter fertilizer refers to fertilizer applied to the soil to support young seedlings or repotted plants to help meet their nutrient requirements as they grow new roots. These fertilizers are applied close to the base of the plant, unlike other fertilizers, to ensure that the nutrients are easy to absorb.
Starter fertilizers are useful in home gardens and farms and are particularly important economically for improving crop yields. The fertilizers encourage the plants to grow up healthier, stronger, and faster by supplying necessary nutrients when the plants are young.
The Purpose of Using Starter Fertilizer
The main aim of starter fertilizers is to supply the seedlings with valuable plant nutrients early in the season to ensure that they grow stronger and fast with early maturation. The nutrients supplied by starter fertilizers are the macro plant nutrients, which are nitrogen, phosphorus, and potassium.
Receiving necessary nutrients when they are younger ensures a hardier plant that is able to produce large yields with better quality. These yields are also accessible faster than in plants that don’t receive starter fertilizer.
Starter fertilizers are typically high-quality fertilizers with nutrients most required by the seedlings. The macronutrients that need to be supplied depend on the seedling, but most plants do well with phosphorus-heavy or nitrogen-heavy fertilizers.
Starter Fertilizers Help with the Root Development of Young Plants
These nutrients are responsible for plant growth, as nitrogen helps plants produce the amino acids needed for life, while phosphorus contributes towards root growth.
The application of starter fertilizers offers these necessary nutrients to the limited root system of seedlings or recently pruned plants, which would otherwise struggle to draw nutrients from the soil around them.
Phosphate or phosphorus is particularly difficult for plants to absorb. The roots need to be in close contact with phosphorus-rich soil in order to take in as much of the nutrient as necessary, which is difficult for plants without established root systems.
Starter fertilizers supply these nutrients to the limited root systems of seedling or repotted plants without resulting in any fertilizer burn.

Composition of Starter Fertilizer
Starter fertilizer is typically made up of the three macronutrients that plants need, which are:
- Nitrogen
- Phosphorus
- Potassium
Unlike other fertilizers, starter fertilizers tend to have a higher ratio of phosphorus or nitrogen, as these are particularly important nutrients to promote root and leaf growth. Receiving these essential nutrients allows the plants to grow faster and stronger.
The composition of the plant macronutrients in fertilizers is written out as NPK, with the N standing for nitrogen, P for phosphorus, and K for potassium. Starter fertilizers typically have an NPK ratio of 1-2-1, 1-3-1, or 1-5-0 to ensure that the plants receive the nitrogen and phosphorus they need.
High phosphorus fertilizers are preferred for plants such as tomatoes. Tomatoes need extensive root growth to ensure that you can fertilize them constantly through their growing season without burning them.
Annual flowering plants, cabbage, cucumbers, and similar plants need a medium amount of phosphorus in their starter fertilizers. Meanwhile, flowering and ornamental plants do well with a higher concentration of nitrogen in their starter fertilizer, with ratios like 24-20-15.
Starter Fertilizer Must Be Water-Soluble
An important feature of these starter fertilizers is that they should all be soluble in water. As the starter fertilizers are placed close to the base of the plants, they need to be easily soluble in water to ensure that they do not burn the plants.
The water starts breaking the fertilizer down, mixing it with the soil, and allowing the plants to draw the nutrients and water up. The water holds off the desiccation caused by fertilizers, preventing fertilizer burn.
Starter Fertilizer Can Be Customized or Reformulated
You can make your own starter fertilizer blend by mixing single nutrient fertilizers till you get the ratio that you need for your plants.
While earlier starter fertilizers comprised only the macronutrients, modern starter fertilizers are being used to supply micronutrients like calcium and magnesium to the soil as well. The micronutrients in question are determined based on the needs of the plants, as well as soil analysis to determine what plant micronutrients are missing from the soi.
Starter fertilizers can be solid or liquid, just like other fertilizers. Liquid fertilizers are more expensive but easier to use as you can distribute the nutrients more evenly and prevent fertilizer burn caused by indiscriminate use.
Is Starter Fertilizer Stronger Than Regular Fertilizer?
Starter fertilizers tend to be rich in the nutrients needed by plants to help them grow faster and stronger.
Starter fertilizers are stronger than regular fertilizers, with higher concentrations of phosphorus and nitrogen. The concentration is higher to accommodate the fact that starter fertilizer must be diluted before application to prevent fertilizer burn and encourage nutrient absorption.
Before application, starter fertilizers must be dissolved in water to the ratio of one to two level teaspoons (4.2 – 8.4 grams) of fertilizer to one gallon (4.55 L) of water.
You can even use regular fertilizers to make starting solutions for your plants, as long as they are highly water-soluble. Single nutrient or blended commercial fertilizers should be dissolved into a stock solution by mixing fertilizer with water in a 1:1 ratio.
Then this mixture will need to sit for a bit to allow the sediments to settle down. The clear mixture can be mixed with water in a 1:9 ratio and then used as a starter solution for your plants.

Using Starter Fertilizer Correctly
Using starter fertilizer is not unlike using regular fertilizers. However, starter fertilizers should be applied with care, heavily diluted, and in the exact quantity required by the seedlings.
Here are the steps to using a starter fertilizer correctly to help your seedlings or recently repotted plants thrive.
- Get a soil analysis done. To analyze your soil, you’ll need to take a soil sample and send it to be analyzed to see what nutrients your soil has. Ideally, you should get your soil analyzed every two years.
- Confirm the needs of your plants. Check what kind of plants you have and what nutrients would benefit them the most at the early stages of your growth before you purchase your fertilizer.
- Make or purchase the fertilizer with the right nutrient mix. Based on the nutrient deficiencies in your soil and the requirements of your plants, mix up the right NPK mix in your starter solution with water-soluble fertilizers.
- Ensure that your fertilizer is sufficiently diluted. Dilute your fertilizers to ensure that they supply nutrients to your plants without shocking them.
- Calculate the amount of fertilizer needed for your plants. Ensure that you don’t use more fertilizer than necessary by checking your plant’s needs. Smaller plants and vegetables will be happy with about 8 ounces (236.6 ml) of diluted fertilizer, while the bigger ones can take up to 16 ounces (473.2 ml). Trees can take about a gallon of fertilizer.
- Apply the fertilizer at the time of transplant. Starter fertilizer, as the name suggests, is intended for use at the beginning when your plant is still a seedling or newly transplanted. Pre-water the plant before repotting to ensure that it can absorb the starter fertilizer.
- Ensure that the fertilizer is applied close to the base of the plant. Seedling and repotted plants do not have extensive root systems. Applying the starter fertilizer near the base of the plant ensures that the roots are able to absorb the nutrients. The fertilizer must be diluted, or the roots will burn.
How Often Should I Use Starter Fertilizer?
Starter fertilizer is a fertilizer with specific nutrients that are diluted for use on seedlings or repotted plants.
Starter fertilizers only need to be used one time, when the seedlings are planted or when the plants are repotted. After applying the fertilizers, the plants should be allowed time to adjust to their new environment, recover from transplant shock, and grow new roots.
If gardeners don’t apply starter fertilizers, plants draw nutrients from the soil directly. This is not immediately possible for seedlings or plants who have had their roots pruned, which leads to a period where the plant exhibits signs of transplant shock.
Starter fertilizer is intended as a nutrient boost that prevents transplant shock or supports the plant to recover faster, and hence only needs to be used at the time of transplantation. You can use regular fertilizer on your plants about 4-6 weeks after repotting them.
Final Thoughts
Starter fertilizers are not necessary but worth it to help transplanted plants and young seedlings. These fertilizers support plants through the recovery process by helping them overcome transplant shocks and grow roots and leaves faster.
By supplying plants with necessary nutrients like phosphorus and nitrogen at the early stages, you can ensure larger yields from your vegetables, fruits, ornamental plants, and even crops.