application of bone meal

Question

Which season(s) is best for application of bone meal to a large mixed perennial flower garden? Is it okay to just scatter bone meal around each plant group? How many applications each year?

My plants seem to love it but I don’t want to overdo it.

Answer 1

Your garden is gorgeous! Concerning bonemeal: first, a word of caution. Regular additions of bonemeal without soil testing runs the risk of phosphorus levels that are too high and harmful. Unlike nitrogen, phosphorus moves through the soil very slowly. This is why it is sometimes recommended to add bonemeal to the bottom of the hole when planting bulbs. It will take a long time for surface-applied bonemeal to reach a bulb’s roots. Factors like pH, soil biome and type of phosphorus used all affect the ability of plants to utilize it. If you know your soil is low in phosphorus, bone meal works too slowly to correct deficiencies. Compost has more bio-available phosphorus than bonemeal and has less of a problem with run off which pollutes waterways. This is probably a more weedy answer than you were hoping for. But, there is a push underway to rethink the routine use of phosphorus in gardens. Intensive crop growing, as in agriculture, depletes phosphorus and additions are needed in that setting. Adding bonemeal in spring or fall is fine as long as it is worked into the top few inches so it doesn’t run off in heavy rain. Here is more reading:
https://www.gardenmyths.com/bone-meal-organic-fertilizer/
https://forums.botanicalgarden.ubc.ca/threads/bone-meal-nightmare.50292/
https://s3.wp.wsu.edu/uploads/sites/403/2015/03/bonemeal.pdf