Bone Meal

Bone meal is almost exactly what it sounds like: ground up bones. I say almost, because bone meal also contains cleaned slaughterhouse waste products, much the way blood meal is processed.

Femur of extinct elephant (Welcome Images) CC BY-SA 4.0

Bone meal is an organic fertilizer, high in phosphorus (as much as 15%). Bone meal also contains 3% nitrogen. Those minerals are released into the soil at a rate that is dependent on how finely everything was ground up, and on soil acidity. Coarse grindings take longer to break down.

Bone meal labeling can be a bit confusing. And phosphorus from bone meal is only available to plants if the soil pH is below 7.0. It is often suggested that bulbs be given additional phosphorus, but this is not necessarily true in all regions. That being said, lavender plants devour phosphorus and may need supplementing.

French lavender

Before feeding plants or amending soil with bone meal, it is very important to have your soil tested by a reputable local lab. Unfortunately, over-the-counter soil tests are too unreliable to be worthwhile. Also, amending your soil with bone meal may attract raccoons or dogs, who will dig up your plants in search of a hidden treat that they will never find.

Invest in a good soil test to see if your garden can benefit from bone meal.