The soil is more than just a place to plant seeds. It is also where the plants will get all the essential nutrients they need to thrive. The three major soil nutrients are nitrogen, phosphorus, and potassium. There are also many soil micronutrients as well. Nitrogen is very important for photosynthesis and is part of what makes the plants green. So a plant that does not have enough nitrogen will tend to be yellow. In contrast, a plant that is receiving too much nitrogen and not enough of the other nutrients will tend to produce a lot of green growth and not very much fruit. Tomatoes are a good example of that. You may have seen that a tomato plant that is big and green and lush with very few tomatoes on it. Phosphorus is very important for root development and fruit development. A phosphorus deficiency will often show up as purple colors on the leaves and the veins. And that's why we fertilize our lawns with phosphorus in the fall because it helps promote healthy root development. Potassium is a really important one for cellular function and it helps with disease resistance and it also really helps with cold hardiness and plants. So that's some of the reasons why it's important to have enough of what we call our macronutrients, nitrogen, phosphorus, and potassium. If you've noticed signs of nutrient deficiency in your garden, you can add compost or manure and you can also add fertilizer. If you're going to fertilize your garden, be sure and take a soil test first and you can work with your extension educator to help interpret the results. For the University of Wyoming Extension, I'm Caitlin Youngquist and you're watching From the Ground Up.