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Tomato Gardening: Fish Fertilizer for Tomatoes

It has long been believed that fish help to build up soil and improve plant growth. Native Americans in North America were known to plant their corn and fertilize it by burying a fish alongside it. Even with all the improvements to agriculture that have come during the last few centuries, fish fertilizers are still often talked about by gardeners for their tomatoes and other fruits and vegetables. So, how and why does fish work as a fertilizer?

What is fish fertilizer?

Fish fertilizer is an emulsion or liquid that is made by blending together byproducts of fish, including bones, heads, tails, etc. It is a natural product that uses pieces that would otherwise go to waste. It is high in macro and micro-nutrients needed by plants.

What kind of nutrients are found in fish emulsion?

Fish emulsion fertilizer is a great source of nitrogen, phosphorus, and potassium, the 3 key macronutrients needed by tomatoes and other plants. Along with the big 3, fish emulsion also contains approximately 60 trace elements including: magnesium, calcium, carbon, sulfur, chlorine, sodium, and more.

How is fish fertilizer applied to tomatoes?

Fish fertilizer is most often sold as a concentrated liquid that can be mixed with water and applied as a foliar spray. Fish emulsion can also be homemade using various different recipes. Watering the tomato plant and the soil around it with the fish emulsion can quickly and effectively provide nutrients. 

Are there any other benefits of fish emulsion?

Fish emulsion is a natural fertilizer that will not harm or burn your plants, unlike many synthetic ones. Fish also improves the soil by feeding the microbes that breakdown matter and aerate the soil. The activity of these microbes will continue to provide strong, steady nutrients to your tomatoes throughout the growing season.

Is fish fertilizer the best fertilizer for tomatoes?

While there are many benefits to using fish as a fertilizer for your tomatoes, there are some drawbacks as well. Fish is high in nitrogen and lower in the other two key macronutrients (an N-P-K fertilizer ratio of approximately 5:2:2). Higher levels of nitrogen can cause excellent growth of stems, leaves, and foliage, but be less effective at producing fruit. Tomatoes with lots of foliage and no fruit are far from ideal. Fish fertilizer may also not provide the best levels of other trace elements like a complete fertilizer can.

The biggest downside is that fish fertilizer is much more expensive than other similar fertilizers. As a source of nitrogen, there is very little difference between what fish supplies and other sources, yet fish fertilizer is much more costly. Overall, while there is no harm in using fish fertilizer, it probably isn’t worth it.

What is the best tomato fertilizer?

Five generations of tomato growers have passed down their best tips and advice, which has culminated in the creation of Tomato Secret, the best tomato fertilizer on the market. Tomato Secret is a natural fertilizer that give direct nutrition to the plants, feeds the microbes to create healthy soil, and produces beautiful, delicious tomatoes. Skip the limited benefits of fish fertilizer and get your hands on Tomato Secret, the only tomato fertilizer you will ever need. 


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