Plants absorb nitrogen from soil mainly in the form of

Plants absorb nitrogen from the soil in the form of nitrate (${{\mathrm{NO}}_3}^{–}$) and ammonium ( ${\mathrm{NH}}_4^{+}$ ) ions, both of which are water soluble. Nitrate ions are absorbed quickly by plant roots but leach easily. Ammonium ions are attracted to soil particles and move slowly through the soil to plant roots.