Skip to main content

Micronutrients: What are they and why your plants need them

Plants, like all living things, need nutrients to live. There are macronutrients, nitrogen, potassium, and phosphorus for plants, but there are also micronutrients. There are supplements, fertilizers, and home recipes touting the best ways to feed your plants and make sure they’re getting all the nutrients they need, but how can you be sure they work? What even is a micronutrient, why are they important, and, perhaps most importantly, how can your plants get them? Stick around for the rest of the article, because we’re about to explain everything you need to know about micronutrients.

What are micronutrients?

Micronutrients are minerals or elements that plants need for vital functions but only in very small amounts. Different plants need nutrients in different amounts, but which nutrients are necessary is fairly standard. Micronutrients are just as important for plants as macronutrients! They serve important roles in plant development and function, they just aren’t absorbed in as large a quantity as macronutrients.

It’s important to maintain a balance when it comes to nutrients. Deficiencies are no joke, but neither is having too much of a nutrient. Both can cause serious problems for your plants, so caution is important.

A hand gently dropping small blue fertilizer beads onto the soil around a young plants
Image used with permission by copyright holder

What micronutrients do your plants need and why?

The micronutrients that plants need are boron, chlorine, copper, iron, manganese, molybdenum, and zinc. The role nutrients play in plants can be complicated, and some of the nutrients may serve functions we aren’t completely aware of. However, here is a brief summary of what we know so far about the roles of each of these nutrients.

Boron is used in the development and growth of cell walls. It keeps the cells sturdy and helps them develop properly. Without boron, the plant’s cells are weaker, making them more vulnerable, and they often grow deformed or distorted. Boron deficiencies primarily impact the growing points of the plant, leading to dead, deformed, or sickly growth.

Chlorine plays a role in energy reactions. As many of these energy reactions take place in the leaves, that is mainly where you can see signs of chlorine deficiencies. Leaves with a chlorine deficiency will develop yellow spots or splotches and sometimes die if it isn’t corrected.

Copper is important for many reactions involving the growth of plants. It acts as a catalyst, helping reactions along. Some of the reactions it is involved in include the production of proteins and vitamin A. Copper is immobile, meaning that once it is absorbed into the plant it doesn’t move throughout the plant. As such, copper deficiencies appear in young leaves. They curl in on themselves and sometimes turn yellow.

Iron plays several roles in plants. It’s a part of energy transfers, it helps with the fixation of nitrogen, and it plays a part in the formation of lignins, which form cell walls and other support tissues. Iron deficiency is also recognizable when leaves begin turning yellow, however there is a slight difference. Rather than turning yellow all over, or curling and then turning yellow, leaves with iron deficiency turn yellow only in between the veins, which are left dark green.

Manganese is very important for energy intake, especially with photosynthesis. It also helps with the development of plants, particularly in germination. Manganese deficiency also leads to yellowing leaves and stunted development.

Molybdenum plays a role in plant growth, as well as helping to produce enzymes and fix nitrogen. When a plant is deficient in molybdenum, its growth is stunted and its leaves turn pale.

Zinc is crucial for the production of chlorophyll. Without it, plants will suffer stunted growth and discolored leaves.

person-fertilizing-plant
Singkham/Shutterstock

What’s the best way to make sure your plants are getting them?

The best way to be certain beyond a shadow of a doubt that your plants are getting all the micronutrients they need is to test your soil. There are home kits, as well as services where you send a soil sample to a lab, but sometimes local gardening or landscaping businesses will offer this service, too. Talking to your local gardeners or landscapers can help, as they may be able to recommend products or methods to help you specifically based on their familiarity with the area.

There are supplements and fertilizers that contain these micronutrients. However, deficiencies in micronutrients are fairly uncommon in regular garden soil. You most likely won’t need to worry about it, as long as your plants seem to be doing all right.

Now you know everything you need to make sure your plants are properly nourished! Micronutrients are needed in smaller amounts, but they’re just as important as macronutrients. Deficiencies in micronutrients can be serious, but they’re also uncommon.

Testing your soil when your plants begin having issues is a great way to pinpoint the problem and ensure that you aren’t overloading the soil with a particular nutrient when adding supplements. You’re all set to go, so get out there and grow!

Cayla Leonard
Cayla Leonard is a writer from North Carolina who is passionate about plants.  She enjoys reading and writing fiction and…
How to care for desert rose, a gorgeous succulent
Your desert rose care guide
Light pink desert rose flowers

Does your houseplant collection need a stunning new addition? Why not try growing a desert rose? Adenium obesum is a beautiful drought-tolerant flower from the dogbane family. Native to parts of Africa and Asia, this plant’s vibrant flowers and relatively small size when grown in containers make it a wonderful and uncommon houseplant. Curious about growing your own? This guide will walk you through everything you need to know about keeping your desert rose happy and healthy.
Planting desert rose

Desert roses can grow in traditional gardens or in containers, but they are better suited to containers in most parts of the U.S. They prefer warm weather and are sensitive to the cold. Growing your desert rose in a container allows you to bring it indoors during winter to keep it safe and warm.

Read more
Zoysia grass is tough and versatile – here’s how to care for it
Planting and caring for a zoysia grass lawn
Green grass lawn

The basics of lawn care may not change much from one lawn to the next, but many of the finer details do change based on the type of grass you’re growing. If you want the lushest, greenest lawn possible, you’ll need to tailor your care routine to your lawn. Zoysia grass is a popular grass species for lawns, with thick, vibrant blades that require shockingly little care. How do you know if zoysia is right for your lawn, and how do you keep your zoysia lawn looking its best? This guide will answer all your questions.
Planting zoysia grass

Zoysia grass can grow from seeds, sod, or plugs, and all options have different benefits and drawbacks. Seeds are excellent if you have a large area to cover, and they’re generally more affordable. However, zoysia grass grows slowly. Sod and plugs, which are already partially grown, are much faster to establish and begin spreading than seeds. However, they’re more expensive and more time consuming to plant. Some people choose to use a combination of seeds and plugs to get the best of both options.

Read more
This is how to deadhead petunias and encourage new growth
Deadhead your petunias the right way
A basket of colorful petunias

Petunias are beautiful, colorful, and easy to care for. They make excellent additions to most gardens, whether they are traditional gardens, container gardens, or even hanging baskets. If you want to get the most out of your petunia plants, you might be wondering how to deadhead petunias. Deadheading, or the process of removing dead or wilted flowers, can seem intimidating if you’re new to gardening, but the process is actually quite simple. Here’s how to get started deadheading your petunias.
How to deadhead petunias

Begin by finding flowers that are wilted, dead, or dying. When petunias wilt, they begin to close back up, so looking for partially or fully closed petunia blooms is a good way to start. Be careful not to target fresh petunia flowers that haven’t bloomed yet, though! Next, you’ll want to remove the petunia flower using your fingers, a knife, scissors, or garden shears. Make sure your hands or tools are clean to avoid spreading any diseases to your petunia plant.

Read more