Bone meal and blood meal are very different organic fertilizers. Bone meal mainly supplies phosphorus and calcium. Blood meal mainly supplies nitrogen. Neither should be added automatically. The right choice depends on your soil test and what nutrient is actually low.
In many home gardens, phosphorus is already high, so bone meal is often unnecessary. Blood meal can help nitrogen-hungry plants, but it can burn plants or create excessive leafy growth if overused.
For report basics, read How to Read a Soil Test Report.
Last updated: June 6, 2026.
Quick Answer
Use bone meal only if your soil test shows phosphorus is needed or you are planting crops where a phosphorus supplement is justified. Use blood meal when plants need nitrogen and your fertilizer plan calls for it. Do not use either as a routine cure-all.
Bone Meal vs Blood Meal
| Product | Main nutrient | Best use | Main risk |
|---|---|---|---|
| bone meal | phosphorus, some calcium | low-phosphorus soils, bulbs, planting amendments | over-applying phosphorus |
| blood meal | nitrogen | leafy growth, nitrogen side-dressing | burn, too much foliage |
What Bone Meal Does
Bone meal is a slow-release organic phosphorus source. It is often marketed for roots, bulbs, flowers, and fruiting crops.
Use caution because:
- phosphorus does not leach as easily as nitrogen
- many gardens already have enough phosphorus
- excess phosphorus can affect water quality
- high pH soils may limit phosphorus availability
- pets may dig where bone meal is applied
Do not add bone meal just because tomatoes are blooming. Check the soil first.
What Blood Meal Does
Blood meal is a high-nitrogen organic fertilizer. It can green up nitrogen-hungry crops quickly compared with many slow organic amendments.
Good uses:
- leafy greens that need nitrogen
- nitrogen side-dressing based on crop needs
- compost pile nitrogen boost in small amounts
- soils low in nitrogen where phosphorus is already high
Avoid heavy applications around young seedlings.
Which Is Better for Tomatoes?
Tomatoes need balanced fertility, not just one amendment. Too much nitrogen can produce lush vines with fewer fruits and can contribute to blossom end rot risk through fast vegetative growth and water demand.
For tomatoes, start with:
- soil test
- compost in moderation
- fertilizer matched to the report
- steady watering
- mulch
For tomato-specific fertilizer, read Best Fertilizer for Tomatoes.
When to Avoid Bone Meal
Avoid bone meal if:
- phosphorus is high
- soil test does not recommend phosphorus
- pets dig in the garden
- growing in containers with unknown pH and salts
- using manure or manure compost regularly
- applying complete fertilizer already containing phosphorus
When to Avoid Blood Meal
Avoid or reduce blood meal if:
- plants are already dark green and leafy
- tomatoes are growing vines but few flowers
- seedlings are small
- soil is dry and plants are stressed
- you cannot measure the rate accurately
- pets or wildlife are attracted to animal-based amendments
FAQ
Can I use bone meal and blood meal together?
Yes, but only if your soil needs both phosphorus and nitrogen. Many gardens need nitrogen more often than phosphorus.
Is bone meal good for blossom end rot?
Usually no. Blossom end rot is often about calcium movement and water stress, not simply lack of calcium in soil.
Is blood meal fast acting?
It is faster than many organic fertilizers, but still depends on moisture, soil biology, and temperature.
Related Reading
- Best Fertilizer for Tomatoes
- Why Tomato Plants Need Calcium
- Epsom Salt for Plants: Useful or Myth?
- Compost vs Manure: Which Is Better?