Synthetic hydroxyapatites as high-performance fertilizers for lettuce plant growth

Although bone residues, constituted mainly by hydroxyapatite, have been used as fertilizers at a small scale for a long time, few studies have focused on their use as plant growth promoters. In this study, synthetic hydroxyapatites of varying compositions were produced and tested as fertilizers to promote lettuce growth in water. The results show that all synthetic hydroxyapatites, containing Ca, Ca and Mg, or Ca and K, increased lettuce height between 275 and 350% in 30 days compared to the control. The hydroxyapatite containing 30% of K was the most effective as it promoted best plants growth.