At our Estate Grown Hawaii farm we only use the lateral Hiwa roots, the roots of the Hiwa plant with the highest concentration of the active ingredient. We do not use any kind of fillers, stems or leaves in our Hiwa products. Certified Authentic: The plant took 8.5 years to grow to maturity and three weeks to air dry authentically. EstateHiwa. To appreciate tradition why not engage in one or two.