Gardening is a wonderful way to practice mindfulness. We care for plants as best we can, giving them the chance to grow. We can practice mindfulness, giving our thoughts room to grow.
Take a deep breath in, and then a deep breath out. Now do it one nostril at a time. Otherwise known as Nadi Shodhana Pranayama, nose breathing is just about one of the easiest, most healthy calming and meditation techniques on hand. As long as you're not congested.