You can use compost, which is rich in nitrogen, phosphorus, and other vital nutrients, to help all your plants grow, bloom, and bear fruit.
For Potted Plants: Fill the pot with three parts soil and one part compost, and mix before adding the plant.
For Outdoor Plants and Flowers: Spread compost as you would mulch, placing it between your flower beds, underneath shrubs, and around the bases of trees. It'll act as a blanket, helping to suppress weeds, keep in moisture, and prevent erosion.
For Vegetable Gardens: Distribute a layer of compost (up to one inch thick) over soil just before you till it for planting. It will enhance the soil's texture and its ability to hold water and air, as well as boost the nutrients in your veggies.