Learn how to tell the difference between plants and weeds in your garden! Are you a friend or an enemy?

You’re outside in your garden, maybe appreciating what you’ve done or thinking about what you’re going to plant next. Suddenly, a tiny small sprout pushes its way through the soil. You feel a wave of doubt rush over you. Is it a rare flower you forgot about, a volunteer vegetable seedling from last year’s harvest, or an unwanted weed that is ready to take over? Every gardener plays this fun garden guessing game!

You’re at the correct place since knowing how to tell weeds from plants is a basic skill for gardeners, and you can surely learn it. There isn’t one magic trick that works every time, but you can typically find the answer by paying close attention and learning a few important rules. It’s like learning a new language, the language of plants! This book will give you the investigative abilities you need to easily tell the difference between the plants you love and the ones that are just trying to take advantage of them. We’ll talk about important things to look for, common things that might try to trick you, and ways to help you make the proper choice so you can take care of what you love and deal with what you don’t. Let’s get going on your path to being an expert at identifying plants and weeds!

What Is a Weed, Anyway? Defining the “Enemy”

Before we talk about how to identify a weed, let’s make sure we know what we mean by “weed.” You might be surprised to hear that the word isn’t always clear-cut.

A weed is a plant that is growing where it shouldn’t be, or a plant that is out of place. This is the most common and frequently recognized definition. In this case, a gorgeous rose bush blooming in the center of a carefully designed vegetable patch could be called a weed, even if it is a prized plant in another setting.

This makes a very important point: the word “weed” is often up for interpretation. A dandelion, for example, can be a “pesky weed” to one gardener but a therapeutic plant, a food source for bees, or even a nice splash of color to another gardener. A lot of the plants we grow now as crops or decorations started out as wild plants that some people may have thought were weeds.

But for most home gardeners and for this article, a “weed” is usually a plant that you didn’t mean to plant and that has certain traits that can hurt your desired plants or the overall look and health of your garden. These are some of the things that are typically included:

• Aggressive Growth and Spread: Weeds grow swiftly and can spread quickly by seeds, runners, or roots that stay in the ground.
• High Seed Production: Many weeds make a lot of seeds, which helps them live and spread for many generations. Imagine one dandelion head releasing hundreds of seeds that look like parachutes!
• Tenacity and Resilience: They are generally very hard to get rid of completely, and some can grow again from even a small piece of root left behind.
• Strong Competitors: Weeds are known for taking light, water, and soil nutrients away from your cultivated plants.
• Presence by accident: For most of us, this is probably the easiest way to tell the difference. If you didn’t plant it and it doesn’t look like something you want to grow, it’s a good candidate for a weed.

A wildflower that pops out could be a nice surprise for one person, but if it threatens to choke out your prize-winning petunias, it’s acting like a weed in your yard. Knowing this can help you identify a mystery plant with a clear goal: to find out if it’s a friend you want to take care of or an enemy you need to deal with.

A Gardener’s Guide to Telling Weeds from Plants You Want in Your Garden

Okay, let’s get to the point: how to become a plant detective by increasing your observation abilities. It might be hard to tell the difference between a tiny weed seedling and a beloved perennial that is just starting to grow. However, there are a few signs you can look for. You can usually figure out what something is by looking at a few of these indications together.

Locationis Important

You may learn a lot from where a plant is growing.

• Pattern of Growth: Did you plant seeds in neat rows or in distinct clumps? If so, the seedlings that grow in that pattern are probably the plants you want. Weeds, on the other hand, tend to grow all over the place without any rhyme or reason, and they don’t care about how well you planned.
• Proximity to Known Self-Seeders: Are you sure that the mystery seedling is growing immediately next to or under a mature plant that you know self-seeds? Many annuals and perennials that people like, such as columbines, poppies, and cosmos, will shed seeds and grow “volunteer” plants nearby. These are often welcome!
• Garden History: What did you plant in that spot last year or the year before? Could the fresh sprout be a perennial that you believed was gone, or an annual that you planted yourself last year that you really liked? We need to jog our garden memory sometimes!

Looking at the Seedling Stage (the hardest test, but very important):

It’s hard to tell what kind of plants they are when they’re still small seedlings because they all appear so much alike.

• Cotyledons (Seed Leaves): Cotyledons, or seed leaves, are the first leaf-like structures to grow from a seed. They don’t always look like the plant’s “real” leaves. The cotyledons of beans are big and meaty, while the cotyledons of grass are long and thin. Knowing what the cotyledons of your planted seeds look like can be quite helpful, even if they don’t always tell you what kind of weed they are.

• True Leaves: The first set of leaves that come following the cotyledons is very important. These are the “true leaves,” and as they grow, they will seem more and more like the leaves of the mature plant. Look at these and compare them to photographs of the seedlings of the plant you want to grow (from seed packs or the internet).
• Reference Images: If you planted seeds, you should have a photo on the seed packet or be able to see pictures of those same seedlings online. This direct comparison is quite helpful. Once you get your eye in, you can easily tell the seedlings of many common weeds.

Leaf Features—A Big Clue:

The leaves of the plant become more and more useful for identification as it grows.

• Shape and Placement:
  • Are the leaves simple (with just one blade) or compound (with several leaflets, like a fern or rose leaf)?
  • What is their general shape? For example, are they oval, round, lance-shaped, heart-shaped, or deeply lobed like a dandelion?
  • Are the edges of the leaves smooth, serrated (toothed), wavy, or lobed?
  • What is the order of the leaves on the stem? Do they alternate (staggered), face each other (in pairs directly across from each other), or whorl (many leaves coming out of the same point)? Many types of plants have leaves that are arranged in a certain way.
• Color and Texture:
  • Touch the leaves, but only if you’re sure it’s not something that will bother you, like stinging nettle. Are they soft, fuzzy, hairy, waxy, shiny, leathery, or smooth and fragile?
  • Look at the color. Is it all green, or does it have a blue, red, or mixed color that might complement a cultivated type you planted? Weeds are frequently a simple, strong green.

Stem Clues:

Don’t forget to look at the stems!

• Growth Habit: Is the stem straight and strong, weak and spreading out, creeping along the ground, or twining and climbing up other plants, like bindweed?
• Shape and Structure: Is the stem flat, round, square (a typical characteristic in the mint family), or ridged? Is it empty or full?
• Surface: Are the stems smooth, hairy, sticky, or do they contain thorns or prickles?

Root System (If You Want to Look at It Gently):

A gentle pull or a careful digging (if you’re willing to risk losing the plant or can accomplish it without too much trouble) can sometimes show you important root traits.

• Taproots vs. Fibrous Roots: Many weeds that keep coming back, including dandelions, dock, and thistles, have a long, deep taproot that makes it hard to pull them out completely. It will frequently grow back if it breaks. Some plants have roots that are more fibrous and branch out.
• Spreading Mechanisms: Does the plant have rhizomes, which are underground stems that spread and grow new shoots, or stolons, which are above-ground runners that root where they touch the ground, like strawberries and some weedy grasses? These signs show that the plant is likely to spread a lot.

Flowers and seeds (if the plant matures—the most important clues):

It’s far easier to figure out what a mystery plant is if you let it grow and bloom and make seeds. However, by that time, a weed may have already created difficulties or laid seeds for future generations.

• Flower Characteristics: The color, shape, size, number of petals, and arrangement of floral parts are all very variable for different types of plants.
• Seed Heads and Seeds: The way the seed heads and seeds look is also a big part of how to tell plants apart.

The “Smell Test” (Which Can Be Helpful):

Gently press a leaf between your fingertips. Does it smell different from other things?

• Some plants, including mint, basil, and oregano, have smells that are unique to them.
• Some weeds can smell strong, such “pineapple weed,” which smells like pineapple, or “wild garlic” or “onion grass,” which smells like onions.

“When in doubt, let it grow out (a little!)” is the Golden Rule of Uncertainty. If you’re really not sure and the plant doesn’t look like an aggressive weed right away (for example, it’s not already 6 inches tall while your targeted seedlings are still small), you can allow one or two of them grow a little bigger. Put a plant tag on each so you don’t forget which ones you’re watching. It will be simpler to tell them apart when they get more true leaves or other traits. But if a plant starts to look like it’s going to take over the garden rapidly, you should intervene quickly!

How to Tell the Difference Between Common Garden Weeds and Plants That Look Like Them

There are some weeds that show up in practically every garden, even if each area has its unique set of common weeds. It might save you a lot of effort to learn how to spot these, especially when they are seedlings. When they are extremely young, these weeds can even look like the plants you want them to look like.

Here are some typical garden weeds and the plants that people might think they are:

• Dandelion (Taraxacum officinale) vs. Young Lettuce or Other Leafy Greens:
  • Dandelion seedlings have a base of deeply lobed or toothed leaves. The lobes frequently point back toward the root. They will eventually grow a hollow stem with a single yellow blossom that is really unique.
  • Lettuce seedlings can also have lobed leaves, however the shape and growth pattern of the plant may be different. Look at the pictures on your seed packet!
  • A big difference is that dandelions release a milky white sap when a stem or leaf is broken.
• Crabgrass (Digitaria spp.) vs. Young Ornamental Grasses or Lawn Grass Seedlings:
  • Crabgrass seedlings usually have wider, lighter green leaves than the grass you want to grow. They grow outward from a central point as they get older, and they often root at the nodes.
  • Good grass seedlings: They will usually match the type of grass you planted or the grass that is already there.
  • The main difference is that crabgrass is usually coarser and spreads out more. Its seed heads, which look like fingers, are also unique.

• Purslane (Portulaca oleracea) vs. Small Sedum or Other Succulents:
  • Purslane has fleshy, crimson stems and small, paddle-shaped leaves that are soft and juicy. It spreads out very little. Some people think purslane is a weed, while others think it’s a delicacy. It’s interesting that it’s edible and very good for you.
  • Sedum seedlings: Different species will have different habits, although they usually grow more erect or in clumps, and their leaves can be different forms.
  • The main difference is that purslane has crimson stems and a very flat, spreading habit.
• Plantain (Plantago major—Broadleaf or Plantago lanceolata—Buckhorn) vs. (Usually very different):
  • Broadleaf Plantain: Has a base rosette of wide, oval leaves with noticeable parallel veins. Makes a thick flower spike that looks like a rat tail.
  • Buckhorn Plantain has leaves that are narrower and formed like a lance, and its flower spike is smaller and more oval.
  • The parallel veins in the leaves are a significant sign of the difference.
• Chickweed (Stellaria media) vs. Some Fragile Groundcovers or Young Dianthus:
  • Chickweed is a low-growing weed that spreads out and has little, oval, pointed leaves that grow on weak stems. It features little white flowers that look like stars. A line of tiny hairs frequently runs along one side of the stem.
  • The groundcovers you want will have their own unique leaf forms and ways of growing.
  • Chickweed has weak, often twisted stems and a single line of hairs, which are good signs that it is not a weed.
• Lamb’s Quarters (Chenopodium album) vs. Young Spinach or Amaranth Seedlings:
  • The immature, diamond-shaped or triangular leaves of Lamb’s Quarters seedlings often have a mealy white or violet coating on their undersides.
  • Spinach and amaranth seedlings will have their own unique leaf shapes. For example, spinach leaves are often more rounded or fashioned like arrows.
  • The mealy coating on lamb’s quarters is a very good way to tell them apart.

Your best bet is to learn about the weeds that grow in your area and garden. Take pictures of the weeds you pull, especially while they are young, so you can make your own reference guide. Many local university extension websites provide great tools for identifying weeds that are specific to your area.

Are you still stuck? Tools and methods for identifying plants and weeds correctly

There will be occasions when a mystery plant has you absolutely perplexed, no matter how good your eyesight is. Don’t worry; you’re not the only one, and there are many places you may go for help solving the issue.

• Take Good Quality Pictures: When you need help identifying something, a clear picture is worth a thousand words.
  • Get close-up pictures of the leaves (both sides), the stem, any blooms or seed heads that are there, and where the leaves meet the stem.
  • You should also snap a picture of the whole plant and how it grows in its environment.
  • Put something in some of the pictures to show how big they are, such a penny or your hand.
• Apps and tools for identifying plants online: technology can be a big help!
  • There are a lot of plant identification apps for cellphones, like PictureThis, PlantNet, Seek by iNaturalist, and LeafSnap. The software uses image recognition to provide possible identifications after you shoot a picture.
  • Pros: It’s quick and easy, and it typically gives surprisingly accurate results for common plants.
  • Cons: It can be erroneous sometimes, especially with very young seedlings or species that aren’t very common. You might need to pay for a subscription to get all the features.
• University Extension Offices and Master Gardener Programs: These are great, trustworthy places to get information.
  • Your local university cooperative extension office probably has a lot of information about local plants, including common weeds, and may even help you identify them.
  • Extension programs train Master Gardener volunteers, who are often ready to help you identify plants at farmers’ markets, garden centers, or by email or phone.
• Reference Books: Don’t forget how useful a good old-fashioned book can be when it comes to gardening!
  • Buy an excellent regional weed identification guide or a general field reference to the wildflowers and plants in your area. These usually feature thorough descriptions and pictures or drawings.
• Online gardening forums and social media groups: The gardening community is big and usually quite helpful.
  • Put your clear pictures on trusted gardening forums or Facebook groups that are focused on identifying plants or gardening in your area. Most of the time, experienced gardeners can quickly and accurately identify plants.
• The “Wait and See” Method (Use with Care and Watch):
  • If you’re still not sure about a seedling and it doesn’t seem to be spreading quickly or outcompeting everything around it, you can carefully mark it and let one or two of them grow a little bigger. It will be easier to tell what kind of plant it is when it has more mature traits, such as the shape of its real leaves, flowers, or general structure.
  • But if the plant starts to act like a weed, such growing swiftly and spreading out or quickly covering up its neighbors, it’s best to get rid of it right once, even if you don’t know what it is for sure. It’s better to be cautious than sorry!

You may greatly improve your chances of gaining a positive identification and making an informed choice regarding your mystery plant by using these resources.

You Made the Call! What now?

After you’ve observed and identified the person and made a choice—friend or enemy—it’s time to act (or not act, as the case may be!).

If It’s a Real Weed:

The main goal is to get rid of it in a way that works and, if possible, before it has a chance to set seed and cause additional issues in the future.

• Hand-Pulling: Hand-pulling works well on a lot of immature weeds or weeds with shallow roots.
  • Tip: Pulling weeds is usually easier when the ground is wet, like after it rains or you water it. This is because the roots will come out more readily and fully.
  • Hold the weed firmly at its base and pull it up slowly, trying to get the whole root system.

• Hoeing: A sharp hoe is great for cutting out immature weeds that are at or just below the surface of the soil. This works well on weeds that grow every year. If you merely take off the top, perennial weeds with deep roots may grow back.
• Digging Out Deep Roots: If you have weeds with big taproots, like dandelions or dock, you’ll probably need a dandelion weeder, a narrow trowel, or even a small shovel to go down and get as much of the root out as you can.
• Mulching to Suppress: A thick layer of organic mulch (2–4 inches) can stop many weed seeds from sprouting by hiding sunlight. It won’t destroy perennial weeds that are already there, but it can stop new ones from growing.
• The most important rule is to get rid of weeds before they go to seed! If one plant goes to seed, that may mean hundreds or thousands of new weeds next year. This is very important for keeping weeds under control over time.
• Disposal: Get rid of removed weeds the right way, especially if they have started to grow seed heads. Putting them in a heated compost pile can kill a lot of seeds, but for really bad weeds, it might be advisable to put them in a bag and throw them away.

If you want to keep a plant that you like (or a “happy accident” volunteer):

Good job! You found a friend.

• Leave It Alone (If It’s in the Right Place): If the volunteer plant is in a good spot where it won’t crowd out other plants and fits in with your garden design, you can just let it grow and enjoy your unexpected addition!
• Move it to a Better area: If the volunteer is nice but in the incorrect area (such a tall sunflower seedling in your low border or a beloved perennial seedling too close to its parent), you can carefully move it to a better spot. Do this when the seedling is still young and give it a lot of water.
• Take care of it: offer it the same proper care—water, light, and nutrients—as you offer your other plants that you planted on purpose.

If you make the correct choice and do the right thing, your garden will be healthier and more attractive, and it will look the way you want it to, not the way weeds want it to.

Conclusion: How to Be a Confident Plant-Weed Detective in Your Garden

It’s not so much about memorizing every plant species as it is about getting better at observing and learning how to read the small (and not so small) signs that plants give off. Every gardener, from beginner to expert, runs into mysterious sprouts from time to time on their trip.

You can feel much more sure about your choices if you learn about the main features of leaves, stems, and roots, the environment where a plant is flourishing, and when and how to use the identification tools that are accessible. For those specimens that are really hard to figure out, remember the rule “when in doubt, let it grow out (carefully!)” But when anything looks really out of place, trust your gut.

Put on your gardening gloves and your detective hat, and go outside to properly look at the plants in your garden. You will be able to tell the difference between your garden friends and your enemies with a little experience, patience, and the advice in this guide. Not only will this save you time and work, but it will also help you make a healthier, more beautiful, and more thoughtfully constructed place for the plants you really love to grow. Happy gardening and happy finding!

Weed or plant? Here are the answers to your Quick ID questions! (Section for Frequently Asked Questions)

Here are some simple answers to some typical problems people have when trying to tell plants from weeds:

How can I identify the difference between a weed seedling and a food or flower seedling I planted?

One of the best hints is where and when. If you planted seeds in orderly rows, blocks, or containers, and seedlings came up exactly where you wanted them to, they are probably the plants you wanted. Weed seedlings, on the other hand, tend to show up in odd locations, often where you didn’t plant anything. Also, carefully compare the first real leaves of the mystery seedling to pictures on your seed packages or pictures of the seedlings you wanted to grow that you can trust online.

Does a plant with a gorgeous flower mean it’s not a weed?

Not always! A lot of weeds that are thought to be aggressive or invasive have flowers that are really pretty. Dandelions have bright yellow blossoms, bindweed has trumpet-shaped flowers that are pretty but quite invasive, and purple loosestrife has purple spikes. A weed is not just a plant with pretty blooms; it’s also a plant that doesn’t belong there, acts aggressively, and tends to outcompete other plants you want.

I allowed a plant I didn’t know what it was grow, and now it’s big and taking over my garden! What should I do?

First, use the tools listed in Chapter 4 (pictures, applications, and local experts) to try to figure out what it is as accurately as you can. Knowing what it is will help you figure out how it grows (for example, does it spread via roots, runners, or only seeds?) and the best technique to get rid of it. Once you know that a weed is an undesired aggressive weed, your major goal is to get rid of it as completely as possible, including as much of the root system as you can to stop it from growing back. This could mean digging for a long time. If it has already set seed, be ready for more seedlings to show up next year. You might want to use a heavy layer of mulch to keep them from growing. For species that are particularly invasive, you may need to check with local sources for specialized ways to control them.

Do all “volunteer” plants, or plants that I didn’t mean to plant, count as weeds?

Not at all! A “volunteer” is just a plant that grew on its own, generally from a seed that fell from a parent plant in the previous season or was carried in by wind or animals. A volunteer can be a very welcome “happy accident.” It could be a seedling of a favorite flower, like a columbine, poppy, or cosmos, a herb that is useful, like dill or parsley, or even a tomato plant that came from a fallen fruit. Finding the volunteer is the most important thing. If you enjoy the plant and it’s in a good position (or can be easily moved), it’s a gift from your garden! If it’s something you don’t want or it’s in a horrible spot, you should treat it like a weed.