Bone Meal: Here’s What You Need to Know

As a gardener, you want your plants to grow up big and strong. To achieve that though, you’ll probably have to boost their health with some sort of fertilizer. In this article, we’ll discuss an effective, yet offbeat, fertilizer: bone meal.

Not only is bone meal organic, but it’s chock full of nutrients. It primarily supplies phosphorus, one of the three primary plant nutrients, but also calcium and nitrogen. A typical NPK rating for bone meal is 3-15-0, which is great for bulbs and flowering plants.

In my opinion, the best thing about bone meal is that it’s environmentally friendly and organic. Using it in your garden is simple and very safe. Read on to learn everything about this fantastic fertilizer!

Good Bone Meal Choices:

What is Bone Meal?

Bone meal
Bone meal aids in root development, flowering and fruiting.

Bone meal is exactly that – bones. It’s usually taken from cows as a slaughterhouse byproduct. The bones are steamed to sterilize them and then ground up. It’s sold as the resulting powder or made into pellets or liquid. It may sound gross, but when you consider how organic material naturally decomposes to feed plants in nature, it makes perfect sense. By using this useful amendment, you’re simply giving your plants the type of amendments they used before modern fertilizers were developed.

Not surprisingly, bone meal is often confused or associated with blood meal. There are two main differences. First, blood meal is made from dehydrated blood. Secondly, it mostly supplies nitrogen instead of phosphorous. Even though the two are similar in that they’re both animal products, they’re not interchangeable.

What Nutrients Are In Bone Meal?

As mentioned, bone meal fertilizer mainly supplies phosphorus (the P in NPK). This is an essential nutrient for plants because it helps them grow.

Phosphorous is the nutrient that, in humans and animals, builds up strong bones. When those bones eventually decompose, they release the phosphorous into the soil where plants can use it. Then, instead of bones, the phosphorous helps the plants build healthy stems, leaves, flowers, and seeds. In some cases, the plants then get eaten by animals or humans, putting the phosphorous back to work at strengthening bones (among other things).

Plants rely on phosphorus to enable photosynthesis, growth, and reproduction (flowers and fruit). It also plays other roles in cellular respiration, DNA, RNA, and energy transfer. In short, without phosphorus, your plants won’t survive. To learn more about why this nutrient and others are so important, head over to our article on plant nutrients.

This garden fertilizer also supplies a good amount of calcium and some nitrogen. However, it’s often used mostly for phosphorus, and calcium or nitrogen is an added benefit for the garden soil.

Benefits of Bone Meal

Applying bone meal to soil
Apply bone meal before planting to give plants a phosphorus boost. Source: Garden Soul

As we mentioned, bone meal is great for helping plants grow. The fun doesn’t stop there though! Adding bone meal to your garden will bring many more benefits, such as:

  • Higher fruit and seed yield
  • Stronger root structure for newly-developing plants
  • Promotes healthy, lush growth
  • Helps to provide pest and diseases resistance
  • Encourages big, beautiful blooms

Bone meal is an exceptional organic fertilizer to add for flowering plants like roses and amaryllis. It also boosts the growth of alliums such as garlic, leeks, and onions. Organic bone meal is often used for establishing lawns since it helps young plants mature quickly. It helps develop a denser root structure and provides calcium for tomatoes to fruit. Overall, it’s one of the products that most people should keep on hand for garden use!

Drawbacks of Bone Meal

There aren’t too many drawbacks to bone meal. However, like any fertilizer, you should be aware of any negative possibilities. Here are some downsides to bone meal fertilizer:

  • It’s slow-release, so it won’t give your plants an immediate boost
  • This isn’t a balanced fertilizer. If your plants need additional nutrients, you’ll have to apply a different fertilizer along with the bone meal.
  • If it isn’t mixed into the soil properly, the smell may attract scavengers. Keep the bag safely stored away where animals can’t get to it.
  • Bone meal is only effective in soils with a pH below 7. Alkaline soil conditions reduce nutrient uptake.

Overfertilization with phosphorus can push out other important nutrients for plants, such as iron and zinc. Plants with too much phosphorous will turn yellow, as well as show symptoms of other nutrient deficiencies. Too much phosphorus can hurt the plant’s chlorophyll production which leads to yellowing leaves (called chlorosis).

Most soil is pretty good at regulating the phosphorus released, so there’s little chance of overfertilization. However, if your soil isn’t phosphorous deficient, you shouldn’t be adding bone meal.

How to Use Bone Meal

Before you add bone meal, test your soil to make sure it needs phosphorous. Otherwise, you risk overfertilizing, which can damage and/or kill your plants. Soil testing services are usually available at local agricultural universities and government offices. You can also purchase a soil testing kit and do it yourself.

Along with phosphorus deficiency, the soil must have a pH of 7 or below for this organic fertilizer to work properly. If your soil is more alkaline, doctor the pH before adding bone meal.

A good rule of thumb is to apply one tablespoon per two square feet of soil (3 cups per 100 square feet). Amounts may vary by the brand you use, so always check the instructions on the package first. When planting, mix the fertilizer in with the backfill soil. If your plant’s already in the ground, sprinkle the bone meal on top and then rake over the soil to mix it in.

For bulbs and other spring-blooming plants, add bone meal as well. Apply 1/2 teaspoon when planting in the fall, scratching it into the soil under the plant. You can then supplement again in spring when you start to add to your spring and summer garden.

After applying, lightly water the soil so the bone meal can start breaking down. It will release nutrients over about four months.

Here’s a quick tip: Check the weather forecast before fertilizing. It’s easiest to apply this when conditions are dry and you can work it into the upper layer of soil.

Where to Buy Bone Meal

You can usually find bone meal online, at garden stores, and even Walmart. Here are some of our top recommendations.

Jobe’s Organics Bone Meal Fertilizer

Jobe's Organics Bone Meal Fertilizer, 4 lb
  • Organic granular fertilizer vegetables, tubers,...
  • OMRI listed for organic gardening by USDA;...
  • 2% Nitrogen, 14% phosphate, and 15% calcium;...

This is a granular bone meal. It is less dusty during application than other types, but has a larger particle size that takes a while to break down.

Miracle-Gro Nature’s Care Organic Bone Meal

Miracle-Gro Nature's Care Organic Bone Meal, 3 lb.
  • Builds a strong frame starting from the roots
  • Just a little shot of phosphorus works wonders in...
  • Gives your bulbs, flowers and roses the extra...

Miracle-Gro has an organic and highly-rated bone meal. It’s in powdered form for easy application and mixing.

Nectar for the Gods Herculean Harvest Liquid Bone Meal

As a liquid form, this bone meal is great for use in hydroponics. It comes with a conversion chart and a pipette.

Frequently Asked Questions

Q: How do I tell if my plants need more phosphorous?

A: Phosphorus deficiency symptoms include stunted growth, delayed maturity, and small fruit set. Also, old leaves may turn purple before dying. It’s difficult to fix the results of deficiency, so the best thing you can do is catch these symptoms early on and apply fertilizer immediately.

Q: Does bone meal carry mad cow disease?

A: No, this is a very safe fertilizer. The animals used to make bone meal are also meat producers, so they’re kept healthy and free of mad cow disease.

Q: Will bone meal pollute water sources?

A: Excess phosphorus can be washed away into natural water sources and cause algal growth. This usually only happens with fertilizers that are water-soluble. Bone meal is generally safe from leaching too much phosphorus into the environment.

Q: Is bone meal fertilizer toxic?

A: Bone meal isn’t necessarily poisonous, but it can cause gastrointestinal distress if eaten by humans or animals. If you have pets or children around, mix it into the soil really well and store the bag where they can’t get to it.

Q: Can bone meal be used in hydroponics?

A: Yes! Bone meal is a great solution if you’re trying to do organic hydroponics. Before using it though, you have to calculate the nutrients needed and how much bone meal you’ll need. For some help with this, we have articles on hydroponic nutrient solutions and general hydroponic nutrients.


Are you ready to try out this natural fertilizer? If done correctly, adding bone meal may be the best thing you’ve ever done for your plants!


The Green Thumbs Behind This Article:

Rachel Garcia
Succulent Fanatic

Lorin Nielsen
Lifetime Gardener

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Last update on 2020-10-28 / Affiliate links / Images from Amazon Product Advertising API