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Understanding the Basics of Fertilizing Tomato Plants

It’s no secret that tomatoes are a delicious addition to any meal. If you’re looking for the best way to grow and harvest the tastiest tomatoes possible, there are some important rules to follow. One key to success is to understand the importance of fertilizing. From using a sea salt fertilizer to adding compost and composted manure, there are numerous ways to ensure your tomatoes will be bursting with flavor. Read on to find out the best way to fertilize your tomato crop!

Finding the Best Fertilizer for Tomatoes

When it comes to figuring out the best fertilizer for tomatoes, there are a few things to keep in mind. A higher number in the middle of the ratio indicates that some growers prefer a high-phosphorus fertilizer. To make things simple, you can use a tomato-based fertilizer with a ratio of 3-4/6 or 4-7-10. It is important to note, however, that overfertilizing should be avoided at all costs.

When it comes to timing, it is best to wait until flowers start to develop before fertilizing. Once fruits form on the plant, adding a light fertilizer every two weeks until the end of the season is recommended. Following these steps will ensure that your tomato plants receive proper nutrition and yield a high-quality harvest.

For those looking to promote fruiting, water-soluble fertilizers such as 24-8-16 and 18-18-21 provide an adequate amount of phosphorus. For larger tomatoes, some gardeners may prefer to apply 0–45–0 triple superphosphate at a rate of 1/2 cup per 100 feet of row.

When the first tomatoes are small, you should fertilize your tomato plants around two weeks before bloom begins.

The best time to use most fertilizers is in the evening when the sun is waning and the rain has subsided. This will prevent chemical fertilizers from washing through without leaving much benefit in the soil, and they can also prevent them from “baking” in the sun and either losing potency or burning plants.

Choosing the Right Fertilizer for Tomatoes

When it comes to choosing the right fertilizer for tomatoes, there are three main components to consider: nitrogen, phosphorus, and potassium. Nitrogen helps provide the plant with energy to produce fruits, while phosphorus helps with root growth and increases flower production. Potassium is essential for overall plant health and fruit quality. In addition, some trace elements are necessary for tomato plants as well. Fertilizers usually contain a combination of these three components in varying ratios depending on their purpose – such as promoting fruiting or increasing root growth. The packaging will indicate what percentage of each component is present in the fertilizer so you can easily choose one that meets your needs.

Organic fertilizers are a popular choice for tomato plants. Two of the most popular organic tomato fertilizers among the EG team are Espoma Tomato Tone and Espoma Liquid Tomato Food. These fertilizers gradually break down in the soil, providing continuous nutrition to your plants while also helping to build up the soil with good organic material.

For tomatoes, peppers, and eggplants that have flowered and set fruit, liquid balanced fertilizers such as compost tea or comfrey tea are a great choice. The ideal ratio for these fruiting plants is 5-10 with trace amounts of magnesium and calcium added.

Blood and bone meal can be used to increase soil nitrogen and phosphorus levels by adding nitrogen and potassium to manure. Adding Ash, oyster shell flour, seaweed, phosphate rock and compost can help promote healthy and fast-growing tomato plants. These organic fertilizers are easy to find at most garden centers or online.

Making Your Own Homemade Tomato Fertilizer

For those looking to make their own homemade tomato fertilizer, it is possible to do so with a few simple ingredients. To start, fill an empty gallon milk container with water and add one tablespoon of Epsom salt. This mixture can then be applied directly to your tomato plants or put into a clean empty spray bottle for spraying the plants. During the growing season, this homemade fertilizer should be applied every two weeks for optimal results. It is important to note that overfertilizing should be avoided as it can burn the plant’s roots and damage the fruits. In addition, when using any type of fertilizer on your tomatoes make sure you apply it in the evening when the sun is waning and rain has subsided in order for it not wash away before having a chance to benefit your plants.

For those looking for an organic fertilizer, coffee grounds and tea can be a good low-level source of nitrogen. To make a “manure tea” soil drench, combine five to six cups of coffee grounds with five gallons of water. Around the tomato plant, pour one to two cups of this coffee-water mixture for optimal results.

In addition, adding compost and composted manure to the soil is a great way to grow tomatoes and other plants. Compost improves soil structure and adds basic nutrition. All season long, composted manure provides nutrition. Over the growing season, composted manure provides a slow release of nutrients.

Finally, a Sea Salt Fertilizer can be used to improve the taste of tomatoes. Simply put salt on the plants themselves and this will help give your tomatoes that extra flavor boost.

When it comes to reusing soil from tomato plants, it is generally recommended to not use the same soil for tomatoes after two years. However, the soil can be used for growing other vegetables such as flowers, bush beans, peppers and salad greens.


Tomatoes need nitrogen, phosphorus, and potassium, as well as some trace elements, to promote fast and healthy growth. Fertilizers are usually made up of a combination of these three components, and the packaging will indicate what percentage of each component is present. It is important to know when and how to fertilize your tomato plants in order to get the best results. Tomatoes should not be grown in the same soil for more than two years, but the soil can be used for growing flowers, bush beans, peppers, and salad greens. Adding compost and composted manure to the soil can also help improve soil structure and add basic nutrition. With the right fertilizer and care, your tomato plants can thrive and yield a delicious harvest.