Meditation can help. So can going out and experiencing the world around you. Go to the park, find a quiet spot with out other people around. Sit on the ground, or stand with shoes and socks off, let your mind quiet (don't follow your thoughts, just let them come and go on their own) listen to the rustle of leaves, the animal sounds, the chirping of birds. Let yourself feel the connections between all living things. This takes time and you may not get it the first time you try, keep doing it and it will come to you. Once you can feel the energy of the world around you, you can easily pick up the energies of plants or stones.