Skip to main content

The nutrients plants need and the best ways to feed them

Every living thing needs specific nutrients, and they need to get those nutrients from somewhere. Plants aren’t structured like us, and they don’t eat like us either. So what do they need, and how can you get it to them? Here are the most important things to know, condensed into one spot just for you!

What major nutrients do plants need?

There are six major nutrients, three of which are arguably the most important things for plants. The most important three are nitrogen, phosphorus, and potassium, with the other three being calcium, magnesium, and sulfur.

Recommended Videos

Nitrogen is important for every part of the plant. It’s used in plant cells, proteins, hormones, and even chlorophyll. It is a major component of plants, which is why it’s so important that your plants get plenty of it.

Phosphorus is used in the intake of energy from sunlight. It also promotes root health and growth, general plant growth, and flowers, if the plant has them. Flowers with the correct amount of phosphorus tend to have larger, brighter blooms.

Gloved hands holding soil with different colored balls of fertilizer in it
Singkham / Shutterstock

Potassium is important for general health. It improves a plant’s resistance to disease and also helps with the formation and transportation of starches, sugars, and oil. You could imagine potassium as being the blood of the plant. In plants that produce fruit, potassium is used for fruit production.

Calcium is used primarily in the development of roots and leaves. It also promotes general root health.

Magnesium is mainly used in chlorophyll. Chlorophyll is what gives leaves their green color and ability to process energy from sunlight, turning it into usable energy.

Sulfur is used in proteins and in energy production. However, it has another, interesting, use. Sulfur is the source for the distinctive taste and smell most commonly recognized in onions and cabbage.

What trace nutrients do plants need?

There are six important trace nutrients plants need or benefit from. These nutrients are not necessarily less important than the major nutrients, but they are needed in smaller amounts.

Boron is used in the development of cell walls and helps with the intake of calcium. Copper is used in the production of enzymes. Iron is used for regulating growth. Manganese helps plants with photosynthesis. Molybdenum is used by bacteria in the soil to take nitrogen from the air and convert it to nitrogen in the soil that plants can use. Zinc helps with stem and leaf growth.

What are the best ways to get these nutrients?

Ideally, your soil already has everything it needs. However, if you have tested your soil for nutrients and found out it is deficient in one or another, there are some easy ways to add them.

All of these elements are available as garden supplements or are added to fertilizers. Since these nutrients are important for plant health, there is no shortage of products available, making it very easy to add them to your garden. Just be sure to read any instructions carefully!

Wheelbarrow of mulch next to garden
Image used with permission by copyright holder

Compost is another easy way to add some of these nutrients to your soil. Not all nutrients can be reliably added this way, but nitrogen, phosphorus, potassium, calcium, magnesium, and iron can all be obtained through compost.

Nitrogen and magnesium will be present in any compost you make, as they are abundant in the types of organic material compost is made of. Phosphorus and potassium can easily be obtained by adding manure to your compost, which is also rich in nitrogen.

Calcium is mainly added to compost through eggshells, which can also be added directly to your garden without composting first. You can add iron to your compost by adding blood meal or chelated iron.

How can you tell if your plants are getting enough or too much?

The only surefire way to tell is to test your soil. Testing your soil before adding any type of additive is a very good idea in general, since, for as bad as deficiencies in these nutrients can be, having too much of them is also bad. Often, having too much of one nutrient will restrict a plant’s ability to absorb a different nutrient.

Keep an eye out for sudden changes in plant health with no clear cause. If your plants start to wither, and it doesn’t seem to be caused by water, light, or weather, you should test your soil to see if there’s an imbalance in nutrients.

That’s the basic, most important information about what your plants need and how to get it to them! Plants are a lot more complicated than we give them credit for, and these nutrients all play key roles and interact with each other in a delicate balance. When in doubt, test your soil!

Cayla Leonard
Cayla Leonard is a writer from North Carolina who is passionate about plants.  She enjoys reading and writing fiction and…
What exactly is loam soil? Here’s what to know
How to identify and create loam soil
Hands scooping soil out of a flower pot

Most plants need soil to grow in, but not all soil is the same. There are heavy, dense clay soils and loose sandy soils, as well as many soil types in between. Clay and sand are easy to identify, but a soil type that’s less straightforward is loam. Loam soil is something that many plants prefer, but unlike sand and clay soils, which are named after their main ingredient, loam is a bit more obscure.

So, what is loam soil made of, why do so many plants love it, and how can you make it at home? This guide to loam soil will explain everything you need to know.
What is loam soil?

Read more
Here are the best flowers to plant this coming fall season
End the growing season right with these flowers
Scarecrow among fall flowers

What do you do when the summer flowers in your yard get tired and begin to die back? Hit the landscape refresh button with festive autumn color. Depending on your growing zone, late summer or early fall is the time to switch out summer annuals for fall flowers. There are many autumn flowers to choose from, and even some foliage plants that can serve as excellent accents. Whether you're looking for a few small plants to hold your garden over until spring or want to dedicate your entire garden to the season, these fall flowers are a great place to start.
Annual fall flowers

These cool-season annuals will add brilliant color to any garden. Whether you're looking for a few flowers to grow in pots on your front porch or a wide variety to fill your garden with fall beauty, we've got you covered.
Chrysanthemums
Mums display mounds of color in autumn shades of white, peach, yellow, orange, bronze, and red. Even the flower types offer variety, such as button, daisy, spider, quill, pompon, reflex, and incurved flower styles, just to name a few. Around this time of year, you’ll find them everywhere, from the garden center to the grocery store in pots ranging from 2 inches to 2 feet. Mums work virtually everywhere, from tabletop decor to instant container garden color to massed landscape plantings.
Pansies
Pansies deliver long-lasting, cool-season color in nearly every shade imaginable. Heavy, consistent flowering and outstanding versatility make pansies the most useful flower for fall. Use them for annual color beds, mixed container plantings, and even hanging baskets. Traditional varieties grow in mounded forms, while some newer types trail. In mild climates, pansies bloom straight through winter. In colder areas, they'll return to rebloom in spring.
Violas
These small-flowered relatives of pansies offer greater resilience to adverse growing conditions with perhaps even heavier flowers than their cousins. Violas come in seemingly endless color options, including many multicolor blooms. They offer outstanding cold tolerance and perform well in soggy, wet weather. The small flowers work best in locations where they'll be seen from a close distance, such as annual beds in high-traffic areas or in container gardens.
Dianthus
Dianthus offers masses of brilliant color and delightful aroma. This low-growing annual comes in a range of colors in white, pink, red, and purple tones to complement any garden. Use them in containers or mass plantings,; however, be sure to grow them where you can thoroughly take in the fragrance.
Snapdragons
Snapdragons are perfect for the shoulder seasons, preferring the cool days of fall and spring to the sweltering summers. With both dwarf and standard varieties to choose from, snaps are useful for borders, adding height to mixed garden and container plantings, and they hold up quite well as fresh-cut flowers. In mild regions, snapdragons return to flower again in spring.
Ornamental peppers
These veggies are meant to be seen, not eaten, and they're just right for autumn. The small, colorful peppers ripen to shades of yellow, orange, red, and purple. With several varieties available, the fruits come in different shapes and sizes, from the globe-shaped "Black Pearl" to the "Chilly Chili," which looks like tongues of fire.
Fall accent foliage

Read more
Should you plant a clover lawn? Read this first
How to know if a clover lawn is right for you
White clover flowers

The classic grass lawn has a certain appeal to it, but it isn’t for everyone. If you’re looking for something more sustainable, eco-friendly, or just more interesting than an all-grass lawn, you might be considering a clover lawn. We’ll help you decide if s clover lawn id right for you, or if your lawn is better suited to grass or a mix of grass and clover. No matter your reason for being interested in clover lawns, we’ll answer as many of your questions as we can in this handy guide to clover lawn care.
What are the benefits of clover lawns?

Clover lawns have benefits for you, your local ecosystem, and your soil. Clovers are nitrogen-fixing plants, meaning they add nitrogen back to the soil overtime, which is good news if you ever decide to plant something else in your lawn. Clover is also easier to plant and maintain than grass. It needs less mowing, fertilizing, and watering than most types of grass.

Read more