Sold at many plant nurseries, bonemeal is a common organic fertilizer consisting of coarsely ground bones, which are dried and steamed before grinding. It is a slow-release fertilizer, providing a steady supply of phosphorus to growing plants throughout the growing season. Gardeners frequently employ bonemeal to feed bulb-born flowers and edible crops such as tomatoes. However, it is beneficial to most plants regardless of the species. Making bonemeal at home is an easy project and is an excellent way to make use of leftover chicken, turkey and rib bones.
Things You'll Need
- Chicken, turkey or cow bones
- Steel wool
- Pillowcase or other cloth sack
- Pressure cooker or large cooking pot with steaming insert
- Baking sheet or wire rack
- Grain mill
Collect bones from your meals, including chicken, turkey and cow bones. Bones are also available through butcher shops.
Boil the bones for 20 minutes then remove them from the water and allow them to cool. Scrub the bones vigorously with steel wool until all remnants of fat, meat and cartilage are removed.
Dry the bones in a pillowcase or other cloth sack. Place the bones inside and lay them on a flat surface outdoors where they can receive direct sunlight for four or more hours per day.
Check the bones after one week to determine if they are thoroughly dried. To check for dryness, lightly bang the bones together and listen for a hollow sound. If they do not produce a hollow sound, return the bones to the sack and allow them to dry for an additional week.
Break the bones apart with a hammer. Leave them in the sack and perform the task on a concrete surface. The pieces should be no longer than an inch when finished.
Place the bone fragments in a pressure cooker or steaming pot. Steam the bones for three hours in the pressure cooker or for five in the steaming pot. To test for doneness, pierce the bones with the tip of a sharp knife. If they're ready, the knife should pierce the bones with minimal resistance.
Remove the bones from the pot and allow them to cool on a baking sheet or wire rack before grinding them.
Place the bones in a grain mill set to a medium grind. Slowly grind the bones to the desired consistency. Fine-ground bone releases its phosphorus quickly, whereas coarse-ground bone releases it over a prolonged period of time.
Tips & Warnings
- Always wear goggles when crushing or grinding bone, since the fragments might injure your eyes.