Does your tomato fertiliser provide the nutrients your plant needs to grow the very best, juicy tomatoes?
If you’re not sure, we’ll walk you through soil nutrition and fertiliser step by step. You won’t believe what a difference it will make to the health and yield of your tomato plant.
The nutrition of your soil is essential for the production of juicy, tasty tomatoes. In fact, preparing the soil properly is the first thing to do before planting tomatoes.
To find out what nutrients and pH levels are in your soil, you can take a sample and send it to a nearby cooperative extension office. Take a look at our blog post Tomato Plant Nutrition: What Nutrients Do Tomato Plants Need to learn more about sampling soil.
There are a number of ways that you can improve your soil through fertilisation. These include adding one or more of the following:
Horse manure has long been used by gardeners as a natural soil amendment and fertilizer But is it beneficial for tomatoes specifically? There are some pros and cons to consider when using horse manure on tomato plants
An Overview of Horse Manure for Gardens
Horse manure provides these general benefits
- Adds organic matter to improve soil structure and drainage
- Supplies a variety of macro and micronutrients plants need
- Releases nitrogen, phosphorus, and potassium slowly over time
- Increases moisture retention in the soil
- Promotes healthy microbial activity in the soil
However there are also some potential downsides of using horse manure
- Can contain weed seeds that will sprout in garden beds
- May spread diseases if not properly composted before use
- Adds significant salts to the soil, which can accumulate over time
- Has an extremely high carbon to nitrogen ratio, which can limit available nitrogen
With proper composting and application techniques, the benefits typically outweigh the risks. But for more sensitive crops like tomatoes, further precautions may be needed.
Why Horse Manure May Not Be Ideal for Tomatoes
While horse manure can benefit many plants, there are a few reasons why it may not be the best choice for tomatoes specifically:
Salt sensitivity – Tomatoes are moderately sensitive to salt accumulation in soil. The salts from repeated horse manure applications can potentially reach levels that negatively impact tomato growth and fruiting.
Nitrogen needs – Tomatoes need consistent nitrogen during most of their growing season. But horse manure provides very little readily plant-available nitrogen and may deprive tomatoes of enough nitrogen when it is needed most.
Soil pH – Horse manure often raises soil pH, while tomatoes prefer slightly acidic conditions. The use of lime as a bedding material in horse stalls contributes to increased pH.
Food safety – For edible crops like tomatoes, there is some risk of contamination from pathogens in improperly composted manure. This is especially concerning for fruits that are eaten raw.
Best Practices for Using Horse Manure on Tomatoes
While horse manure carries some risks for tomatoes, it can still be used judiciously in a tomato garden. Here are some tips:
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Allow fresh manure to compost thoroughly for 6-12 months before application. This reduces pathogens, weed seeds, and salts.
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Mix composted manure into garden beds before planting tomatoes. Avoid side-dressing plants with fresh manure during the growing season.
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Test soil pH annually and amend with sulfur to maintain optimal acidity for tomatoes when using manure.
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Use manure sparingly for tomatoes and rotate applications with other organic fertilizers like blood meal, fish emulsion, etc.
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Ensure proper crop rotation to prevent salt and pathogen buildup from repeated manure applications.
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Water deeply after applying composted manure to help rinse salts below tomato root zones.
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Check tomato plants regularly and watch for signs of nitrogen deficiency, disease, or nutrient toxicity.
Alternative Organic Amendments for Tomatoes
For tomato growers wishing to avoid using manure altogether, here are some suitable alternatives:
- High-quality compost made from plant materials only
- Cover crops tilled under before planting
- Garden char blended into soil
- Worm castings worked into beds
- Rotted hay or straw as mulch
- Wood ash added sparingly
- Bone meal, kelp meal, and other organic fertilizers
- Organic nitrogen amendments like blood meal or feather meal
The key is providing balanced organic matter and essential nutrients through materials that align well with tomato needs.
Horse manure can certainly benefit the home garden but may not be the best choice for tomatoes specifically. Due to tomato preferences for consistent nitrogen, slightly acidic soil, and low salt levels, horse manure has some drawbacks. With care taken to properly compost, occasionally rotate applications, and monitor soil conditions, the advantages of horse manure can outweigh the risks. For tomato growers wishing to avoid manure, alternative organic amendments can be used. Paying close attention to each crop’s needs allows gardeners to make informed fertilizer choices.
Tomato Fertiliser: Chemical Fertiliser
Usually, the amount of Nitrogen (N), Phosphorous (P), and Potassium (K) in a compound chemical fertilizer is written on the label. In some places, this is given as a percentage, like 5-10-10, 5-20-20, or 8-16-16. All of these are great for making the soil more fertile before you plant tomatoes.
Sometimes, the quantities are described as a ratio. For instance, what you might call 5:12:5 turns into 2:3:2 (22), where the number in brackets shows the total percentage of nutrient units in the fertilizer. This format, 2:3:2, which is also often added to the soil where tomatoes will be grown, contains 6. 28% nitrogen and potassium and 9. 44% phosphorous.
Chemical fertilizers that are nitrogenous, phosphatic, or potassic are also easy to find and can be used as “side dressing” once the plants are established. Around tomato plants once they start to flower, you should sprinkle a little nitrogenous fertilizer (about 8 g per m²) and a little more potassic fertilizer (about 20 g per m²). Organic potassium or nitrogen products may be used instead.
Tomato Fertiliser: Manure and Compost
Manure has been used as fertilizer for hundreds of years, even though some people say it’s not really a fertilizer.
People in Britain in the 1800s, who were great gardeners, used chemical fertilizers because they thought “science” could solve all problems. In the early 1900s, studies showed that chemicals were not a good replacement for “dung manuring.” However, chemical fertilization continued to grow. This was made worse by the fact that horses were replaced by cars that ran on gasoline and made a different kind of muck!
Adding a lot of organic matter, like compost and manure, to the soil is without a doubt the best way to make it “fertile” for your tomato plants. Not only does organic matter keep nutrients from washing away from the soil, but as it breaks down, it releases its own vitamins and minerals into the soil.
Various types of composts are available from nurseries and garden stores, including rich mushroom compost. If you want to make your own mushroom compost, all you have to do is recycle your kitchen and garden waste. Learn the ways of DIY composting in our blog post, How to Make Compost.
Is Horse Manure Good for the Garden?
FAQ
What is the best manure for tomatoes?
When should you not use horse manure?
What vegetables don’t like horse manure?
Can you put too much horse manure in your garden?
What can I do with horse manure?
Mulching: Complement the benefits of composted horse manure by adding a layer of organic mulch on top of it. This conserves moisture, suppresses weeds, and further enriches the soil over time. Companion Planting:
Is horse manure good for plants?
Nitrogen is vital for leaf development, phosphorus for roots and flowers, and potassium for overall plant vigor and fruit quality. An excess, particularly of nitrogen, can lead to lush foliage but poor fruiting, which I avoid by using horse manure—it releases nutrients slowly, reducing the risk of over-fertilization.
Is horse manure good for Tomatoes?
Let’s talk about why horse manure can be a top pick for your tomatoes, alongside other options like cow and chicken manure. Horse Manure: It introduces organic matter and valuable nutrients into the soil, supporting vigorous plant growth. Prioritize aged or composted horse manure to prevent the risk of ‘burning’ your plants with excess ammonia.
Can you plant tomato seedlings in horse manure?
When preparing to plant tomato seedlings, ensure that the horse manure compost is well mixed into the soil. Never plant tomatoes directly into manure, as manure alone does not provide the necessary minerals for your plants and may result in fertilizer burn.
Can you use composted horse manure to fertilize tomato plants?
Composted horse manure offers several advantages when it comes to fertilizing tomato plants in an organic garden. First and foremost, it is a natural and sustainable option that aligns with the principles of organic gardening. By using composted horse manure, you avoid the harmful effects of synthetic fertilizers.
Can you grow tomatoes in horse poop?
When growing tomatoes, horse poop is the manure of choice. There is absolutely no doubt that the best way to make the soil for your tomato plants “fertile” is to add large amounts of organic matter in the form of compost and manure.