13 Weeds With Blue Flowers: Identification and Control Methods

Last Updated on July 8, 2022 by Kimberly Crawford

If you’re like most people, you probably think of weeds as pesky plants that need to be eliminated as quickly as possible. However, did you know that some weeds can actually be quite beautiful?

In this blog post, we will discuss one type of weed with blue flowers- the butterfly weed. We will talk about its identification and control methods. So if you’re looking to learn more about these lovely plants, keep reading!

In this article

1. Asiatic Dayflower (Commelina communis)

Commelina communis

What is Asiatic dayflower?

Asiatic dayflower is a species of flowering plant in the dayflower family. It is native to Asia, but has been introduced to many other parts of the world.

This weed can be found in lawns, gardens, and waste areas. It is a problem in crops such as rice, soybeans, and peanuts. The Asiatic dayflower is an annual plant, meaning it completes its life cycle in one growing season.

What does it look like?

Asiatic dayflower is an annual herb that can grow up to 50 cm tall. The leaves are lanceolate to ovate, with a pointed tip and smooth edges. They are arranged in pairs along the stem. The flowers are blue or violet, and they have three petals of unequal size.

The central petal is the largest and the two side petals are much smaller. The flowers are borne in the leaf axils, and they bloom from summer to fall.

How to get rid of it?

The Asiatic Dayflower spreads rapidly by seed and can form dense mats that crowd out native plants. Hand-pulling is the most effective method of control for small infestations. For large infestations, herbicides may be necessary.

If you have this weed in your garden, the best way to get rid of it is to pull it up by hand. You can also use a hoe or other tool to loosen the soil around the plant and then pull it up. If you have a large infestation, you may need to use an herbicide. Be sure to follow the instructions on the label carefully.

You can prevent this weed from spreading by keeping your garden free of debris and weeds. You should also avoid disturbing the soil around established plants. If you must disturb the soil, be sure to rake up any weed seeds that may have been dislodged.

2. Blue Oxalis (Parochetus communis)

Parochetus communis

What is blue oxalis?

Blue oxalis (Parochetus communis) is a species of flowering plant in the family Oxalidaceae, native to tropical Africa. The plant has blue flowers and is used as an ornamental plant in gardens.

The blue oxalis is a perennial herbaceous plant that grows up to 30 cm tall. The leaves are alternately arranged and are compound with three leaflets. The flowers are blue or violet in color and have five petals. The fruit is a capsule that contains seeds.

How to identify blue oxalis.

The leaves are trifoliate, with each leaflet being ovate to lanceolate in shape and arranged in a rosette at the end of the stem. The flowers are borne in clusters of up to 30 and are pink, purple or white in colour. The fruit is a small capsule containing four seeds.

How to get rid of blue oxalis.

If you don’t want blue oxalis in your garden, there are a few things you can do. You can try to pull it up, but be careful not to disturb the roots of nearby plants.

You can also try to smother it with mulch or newspaper. Finally, you can use a herbicide that contains glyphosate. Just be sure to follow the instructions on the label.

3. Bush Vetch (Vicia sepium)

What is bush vetch?

Bush vetch (Vicia sepium) is a climbing plant in the legume family. It is native to Europe and Asia but can also be found in North America. This climbing plant can grow up to six feet tall and has small, blue-violet flowers.

The flowers bloom from June to August and are followed by seed pods that contain two to four seeds. Bush vetch is a nitrogen-fixing plant, meaning it helps improve soil quality by adding nitrogen to the soil. This makes it a good plant to grow in areas that have poor soil quality.

How can bush vetch be used?

Bush vetch can be used in a variety of ways. The leaves and shoots can be eaten raw or cooked, and the peas can be used like any other legume.

The plant can also be used as a cover crop or green manure. When plowed under, bush vetch adds nitrogen to the soil. It is also a good bee plant, providing nectar and pollen for bees early in the season.

How to identify bush vetch.

Bush vetch is a member of the pea family, and like all members of that family, has pinnate leaves. The leaflets are oval with smooth edges, and the stipules are large and conspicuous. The flowers are borne in racemes.

Bush vetch can be found in hedgerows, woodlands and on roadside verges. It flowers from May to August.

How to get rid of bush vetch.

There are a few ways to get rid of bush vetch, but the most effective method is to physically remove the plant. This can be done by pulling up the plant by its roots or by using a hoe or other gardening tool to dig up the plant.

If you have a large area infested with bush vetch, you may need to use a herbicide. Glyphosate is a common herbicide that can be used to kill bush vetch. Be sure to follow the directions on the glyphosate label carefully to avoid harming other plants or animals.

Another way to prevent bush vetch from spreading is to mow it down before it flowers and sets seed. This will not kill the plant, but it will prevent it from spreading. Mowing should be done on a regular basis (weekly or bi-weekly) to keep the bush vetch under control.

4. Carpetweed (Ajuga pyramidalis)

ajuga pyramidalis

What is carpetweed?

Carpetweed is a common weed in lawns, gardens and landscapes. It is a member of the mint family and has square stems with opposite leaves.

The flowers are small, blue or white and borne in terminal spikes. Carpetweed can be found throughout the United States.

What does it look like?

It is a low-growing plant, with small, blue flowers that appear in early summer. The leaves are oval shaped and have a scalloped edge. Carpetweed can be found growing in lawns, gardens, and on roadside verges.

How to get rid of carpetweed.

To get rid of carpetweed, you’ll need to pull it up by the roots. You can do this by hand or with a garden tool. Be sure to dispose of the weed properly so that it doesn’t spread.

You may also want to treat the area with an herbicide to prevent regrowth. Carpetweed is a difficult weed to control, but with persistence, you can eventually get rid of it.

5. Columbine Aquilegia (Aquilegia vulgaris)

ajuga pyramidalis 1

What is columbine aquilegia?

Columbine aquilegia is a species of flowering plant in the buttercup family Ranunculaceae, native to Europe. It is also known by the common names garden columbine and European columbine.

The Latin name Aquilegia is derived from the word “aquila”, meaning “eagle”, because of the shape of the flower petals, which are said to resemble an eagle’s claw.

This plant is a herbaceous perennial that typically grows to 30-60 cm (12-24 in) tall, with a basal rosette of leaves and stem leaves on long petioles. The flowers are borne in racemes or panicles of 15-25 blooms, each flower with five petals that are usually red and yellow.

The plant is found in woods, meadows and rocky slopes in Europe. It has been introduced to North America, where it is now naturalized in some states and provinces.

How to identify columbine aquilegia.

Columbine aquilegia is a herbaceous perennial plant that can grow to be about 30 cm tall. The leaves are alternate, simple, and deeply lobed with each lobe having serrated edges.

The flowers are bisexual and actinomorphic with five petals. They are usually red, purple, or blue in color and have yellow stamens.

The flowers grow in clusters at the end of each stem. The fruits are follicles that contain many seeds.

How to get rid of columbine aquilegia.

If you have columbine aquilegia in your garden and you want to get rid of it, the best way to do so is to dig up the plant and dispose of it.

You can also try cutting back the plant, but this may not be effective in killing it. If you have a large infestation of columbine aquilegia, you may need to use herbicide to kill the plant. Be sure to follow the directions on the herbicide label carefully.

6. Common Blue Violet (Viola sororia)

viola sororia

What is common blue violet?

The common blue violet (Viola sororia) is a species of violet that is native to North America. It is the state flower of Illinois, Rhode Island, and New Jersey. The common blue violet can be found in woods, meadows, and gardens. It blooms from April to June.

The common blue violet gets its name from its blue flowers. The common blue violet is a perennial plant. It grows to be about six inches tall.

The common blue violet has heart-shaped leaves that are dark green in color. The flowers of the common blue violet have five petals and are about one inch wide.

How to identify common blue violet.

The common blue violet (Viola sororia) is a small, delicate flower that can be found in woods and fields across North America. It has heart-shaped leaves and purple flowers with yellow centers.

If you look closely, you’ll see that the petals of the flower are actually two different colors – a deep purple on the outside and a lighter purple on the inside. The common blue violet is the state flower of Illinois, Rhode Island, and New Jersey.

How to get rid of common blue violet:

The best way to get rid of common blue violet is to pull it up by the root. You can also use a hoe or other gardening tool to dig it up.

If you have a large area infested with the plant, you may want to consider using herbicide. Glyphosate is effective against common blue violet, but be sure to follow the label directions carefully.

7. Creeping Bellflower (Campanula rapunculoides)

What is creeping bellflower?

Creeping bellflower is a perennial weed that is native to Europe. It was introduced to North America in the early 1800s and has since become naturalized throughout much of the continent. This invasive plant can be found in all 48 contiguous states, as well as parts of Canada.

Creeping bellflower gets its name from its bell-shaped flowers that range in color from white to blue. The flowers bloom from June to August and are followed by small, round fruits.

This weed is a member of the Campanula family, which also includes the garden bellflower (Campanula poscharskyana).

Creeping bellflower is a problematic weed because it can spread rapidly and outcompete native plants. This invader is particularly troublesome in forested areas where it can form dense mats that prevent the growth of other plants.

Additionally, creeping bellflower produces a large amount of seeds (up to 80,000 per plant!) Which are easily dispersed by wind and animals.

What does creeping bellflower look like?

This perennial plant is native to Europe, but can now be found in North America as well. It has a long, slender stem that can grow up to four feet tall.

The leaves are dark green and have a jagged shape. The flowers are bell-shaped and blue or purple in color. They bloom from June to August.

How to get rid of creeping bellflower:

If you have Creeping Bellflower (Campanula rapunculoides) on your property, the best way to get rid of it is to dig it up. You can also try pulling it up, but be careful not to let the roots break off, as they will just grow back.

If you want to try a chemical method, you can use an herbicide with the active ingredient glyphosate. Be sure to follow the directions on the label carefully.

8. Forget-me-not (Myosotis scorpioides)

Myosotis scorpioides

What is Forget-me-not?

Forget-me-not is a small, delicate flower that blooms in the spring. The name forget-me-not comes from the Greek myth of Orpheus and Eurydice.

According to the story, Orpheus was so distraught after his wife Eurydice died that he went to the underworld to try and bring her back.

As he was leaving, he turned to look at her and she disappeared forever. The forget-me-not flower is a symbol of love and remembrance.

Forget-me-nots are found in temperate regions all over the world. They grow best in moist, shady areas with rich soil. The flowers are typically blue, but can also be white, pink, or purple.

What does Forget-me-not look like?

Forget-me-nots are small, delicate flowers with blue petals and yellow centers. They grow in clusters and have slender stems that can be up to 18 inches long. The leaves are lance-shaped and arranged in pairs along the stem.

Forget-me-nots are found in damp, forested areas in Europe and Asia. They are also common in North America, where they were introduced by European settlers.

How to get rid of Forget-me-not:

The best way to get rid of forget-me-not is to physically remove it from your garden. This can be done by digging up the plant, making sure to get all the roots.

You can also try smothering it with a thick layer of mulch. If you have a large infestation, you may need to resort to using an herbicide.

Glyphosate is effective, but make sure to carefully follow the directions on the package. You don’t want to damage your other plants!

9. Germander Speedwell (Veronica chamaedrys)

Veronica chamaedrys

What is Germander speedwell?

Germander speedwell is a small, flowering plant that is native to Europe. It has blue or violet flowers and grows in a variety of habitats, including woodlands, meadows, and roadside verges.

The plant gets its name from the Greek word for “ground-dweller” because it often grows close to the ground.

Germander speedwell is a member of the plant family Plantaginaceae, which also includes plants such as foxgloves and mulleins.

The plant was introduced to North America in the early 1800s and has since become naturalized in some parts of the continent. Germander speedwell is considered an invasive species in some areas, such as the Great Lakes region of the United States.

The plant reproduces by seed and can also spread vegetatively through its rooting stems. Germander speedwell can form dense mats that crowd out other plants and change the structure of ecosystems.

The plant is most often found in disturbed habitats, such as roadsides, forest edges, and vacant lots.

What does Germander speedwell look like?

Germander speedwell is a low-growing plant that typically reaches only about six inches in height. The leaves are opposite each other on the stem, and they’re oblong-shaped with slightly toothed edges.

The tops of the leaves are green, while the undersides are often a paler shade. Tiny blue flowers bloom in clusters along the stem from early spring to late summer.

How to get rid of Germander speedwell:

Germander speedwell is a low-growing, spreading plant that can quickly become a nuisance in your garden. If you want to get rid of it, here are a few tips:

  • Hand-pulling is the best method for small infestations. Be sure to pull up the entire root system so the plant doesn’t regrow.
  • For larger infestations, you can use a hoe or tiller to loosen the soil and then hand-pull the plants.
  • You can also smother germander speedwell with a thick layer of mulch. Be sure to reapply the mulch every few weeks to keep the plant from growing back.
  • Herbicides can be effective, but they should be used as a last resort. Be sure to follow the label directions carefully.

10. Henbit (Lamium amplexicaule)

What is henbit?

Henbit is an annual herb in the mint family that is native to Europe and Asia. It has been introduced to North America, where it is now a common weed.

The plant grows to 20-40 cm tall and has square stems with opposite, ovate leaves. The leaves are green with purple spots and have hairy surfaces. The flowers are borne in whorls of three to six and are typically pink or purple.

Henbit is considered a weed because it can spread rapidly and crowd out other plants. It is commonly found in gardens, lawns, and agricultural fields.

How to get rid of henbit:

The best way to get rid of henbit is to pull it up by the roots. If you have a large area infested with henbit, you may want to consider using a herbicide.

Glyphosate-based herbicides are effective at killing henbit. Be sure to follow the manufacturer’s instructions when using any herbicide.

11. Siberian Squill (Scilla siberica)

Scilla siberica

What is Siberian squill?

Siberian squill is a plant. The flowers are blue, and the plant blooms in early spring.

Siberian squill is native to Russia and Siberia. It was introduced to North America in the 1800s as an ornamental plant. Siberian squill grows in woods, fields, and gardens.

What does Siberian squill look like?

Siberian squill is a perennial plant that typically grows to about six inches tall. The leaves are linear and taper to a point at the tip. The flowers are blue or violet and bloom in early spring.

How to get rid of Siberian squill:

Siberian squill is a common weed in gardens and lawns. It’s easy to control if you know how. Here are a few tips:

-Pull up the plant by its roots. This is the best way to get rid of it.

-Cut the plant off at ground level. This will stop it from growing back.

-Apply a weed killer to the plant. This will kill it and prevent it from growing back.

12. Slender Speedwell (Veronica filiformis)

Veronica filiformis

What is slender speedwell?

Slender speedwell is a small, delicate-looking plant that is actually quite tough and resilient. It is a member of the plant family Plantaginaceae, which also includes such common plants as plantain and mullein.

Slender speedwell gets its name from its long, slender leaves, which are arranged in pairs along the stem. The leaves are a deep green color and have a smooth, shiny texture. The small, blue flowers of slender speedwell appear in early summer and are borne on short stems that arise from the leaf axils.

Slender speedwell is native to Europe and Asia, but it has been introduced to North America, where it is now found in many states and provinces. It prefers to grow in open, sunny areas, but it will also tolerate some shade.

Slender speedwell is a low-growing plant that usually only reaches a height of about eight inches (20 cm). However, in ideal conditions, it can reach up to two feet (60 cm).

How to get rid of slender speedwell:

Slender speedwell is a pesky weed that can quickly take over your garden. The best way to get rid of it is to pull it up by the roots. However, this can be tricky as the roots are very slender and easily break.

Another method is to use a weed killer, such as glyphosate. This will kill the weed, but it will also kill any other plants that it comes into contact with. So, use this method with caution.

13. Tiny Bluets (Houstonia pusilla)

Houstonia pusilla

What is tiny bluets?

Tiny bluets (Houstonia pusilla) is a small, delicate flower that is native to North America. The flowers are white or pale blue in color and have five petals. They grow in clusters on slender stems and can be found in woods, meadows, and fields from May to July.

The plant gets its common name from its small size and blue flowers. The genus name, Houstonia, is in honor of William Houston, a Scottish-born botanist who lived in the United States during the late 1700s and early 1800s.

Tiny bluets are often used as ornamental plants in gardens and landscaping. They are also known to attract butterflies.

How to get rid of tiny bluets:

The best way to get rid of tiny bluets is to pull them up by hand. If you have a large area to cover, you can use a lawn mower set on its highest setting. Be sure to bag the clippings and dispose of them properly. You can also use an herbicide, but be sure to follow the directions on the label.

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Conclusion

In conclusion, weeds with blue flowers can be a nuisance in the garden. But with proper identification and control methods, they can be managed. With a little time and effort, you can have a beautiful, weed-free garden. Thanks for reading!