plantenvoeding groene kamerplanten 500ml enFertilizers provide plants with the nutrients they need to promote healthy, vigorous growth. They can stimulate the production of new leaves, stems, and roots, as well as encourage the formation of flowers and fruit. It is recommended that you add fertilizer to your plants in the spring and summer. In the winter, plants generally do not need fertilizer, as most plants enter their "dormant" period.