Along with sun and water, fertilizer is needed to make your plants grow. The best time to apply fertilizer to your lawn or other outdoor plants is in the spring.
The numbers on a fertilizer bag give the proportion and relative amount of each of the three main plant nutrients, which are (from left to right):
- Potassium: Prepares plants for stress or cold weather.
Choose a balanced fertilizer (such as 8-8-8) for trees and shrubs in your yard. To limit environmental problems caused by fertilizer running off into rivers and other waterways, choose a fertilizer, like GreenView, that doesn’t contain phosphorus.
Watch this video to find out more.
- Fertilizer 101 (article)
- Debate over Organic vs. Chemical Fertilizers (article)
- Phosphorus Fertilizer in Your Lawn or Garden (article)
- Fertilizer Selection (video)
Danny Lipford: Now one subject we get a lot of questions on – both on our website and on our radio show, Homefront – is all about fertilizers. So, Julie, take us through a little fertilizer clinic here. First of all, when is the best time to fertilize your lawn?
Julie Day: Most people like to fertilize in the spring, right when things start growing and everything turns green. It’s a good time to feed most lawns and most garden plants.
Danny: Ok, and how do you know which one to use?
Julie: There are three numbers on the front of the bag. The first number represents nitrogen; that’s the nutrient that makes things green, it makes the grass blades come up thick and strong. That’s typically the one that’s going to be higher in the spring.
Danny: I see.
Julie: Phosphorus is the middle number. That generally helps plants to grow roots, and blooms, and fruits. So you’ll see that number higher on fertilizers for vegetable gardens a lot of times.
Julie: And the final number, potassium, is kind of an all over plant strengthening nutrient. You’ll see that number higher, a lot of times in the fall, getting ready for winter. Most of the time, a balanced fertilizer with the three numbers the same, like these – these and these both have the same ratio of all three nutrients, that’s called a balanced fertilizer. And that’s usually good for your shrubs and trees, your flowers. If you’re concerned about the phosphorus run off and about pollution in the ground water, you can choose one like this one that doesn’t have any phosphorus in it. It just has nitrogen and potassium, so it’s a little safer for the environment.