10 Weeds With Blue Flowers (Identify by Photo)

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Weed with blue flowers is probably the prettiest weed found in the yards. They look breathtakingly beautiful but their effect is very dangerous. It is a good idea if you get an idea of how to identify them and how to eradicate them from your garden.

Only when you know that blue flower weeds are growing in your garden can you take appropriate measures to control their spread. And eliminate them if they are hurting your other plants.

Here we will tell you about common blue flower weeds that easily encroach on any garden. We will also be adding pictures of these weed flowers so that you can quickly identify them if you see them in your garden area.

10 Common Weed Plants With Blue Flower

Let’s learn about the weeds with blue flowers.

1. Asiatic Dayflower

Asiatic Dayflower 
Image Source: illinoiswildflowers
Types: Commelina Communis

As the name suggests, the Asiatic dayflower is found in East Asia and the northern area of South East Asia. This weed planted first discovered in North America as an ornamental plant. However, it is now considered a brutal weed in many areas.

The Asiatic dayflower is an annual weed that grows all year long. It starts growing from July through to September.

When it first emerges in the spring, it also has broad leaves that give it the appearance of a weed that resembles grass. With no petiole and smooth edges, the leaves are arranged alternately along the stem and usually grow to 2-4 inches.

Asiatic dayflower weed flowers’ features are 3 petals, 2 big blue petals, and 1 little white petal. The spreading dayflower is another kind of dayflower that has three blue petals (Commelina diffusa L.)

How to Control It?

Asiatic Dayflowers are all weed that has been all over the place in your lawn, but you will catch their presence very late. It happens because this plant is very resistant to commercial herbicides.

But whenever you notice it, you need to control its spreading. While other weed plants are invasive to other plants of your lawn, Daydream weeds grow without resistance. Therefore, preventing its growth is difficult.

The very first practical thing you can do is pull it out from the room by hand at first glance. Make sure when you do it, the soil is moist and workable. Because when the soil is dry, the stem will break off from the root and make chances for another plant to grow.

Try to eradicate it sooner than it starts spreading its seeds.

The second method is to use a specific herbicide. Two herbicide ingredients, cloransulam-methyl and sulfentrazone have worked quite well in controlling Asiatic dayflowers.

2. Green Alkanet

Green Alkanet
Image Source: eol
Types: Pentaglottis Sempervirens

Green Alkanet is a very commonly found perennial weed plant. Since it is bright in color and looks attractive, many gardeners let it grow in their lawns along with other weeds. It grows and spreads quickly in moist soil and with less sun exposure.

The green alkanet, a blue flower, belongs to the Boraginaceae family and is identical to the borage and forget-me-not plant. Producing long flower stems covered in clusters of blue blooms with a white center and five petals. Their growing period is between April to June.

How to Control It?

The most effective way to control its spreading is to remove the seedling using hands or hoe very before the growth of the taproot and seeds becomes imperative.

Deep digging is proven effective in removing older plants with taproots, but it’s essential to ensure the root is completely removed to prevent resprouting.

Also Read:- Garden Soil: How to Prepare Garden Soil for Planting?

3. Common Forget Me Not

Common Forget Me Not
Image Source: homestratosphere
Types: Myosotis Sylvatica

This weed is very easy to recognize because of its unique structure. Common forget me not flower is light yellow and has a bright yellow center. The flowers are funnel-shaped and have 5 petals and 5 stamens in them.

Because this flower looks attractive, many gardeners grow it in their gardens. Though this flower is cultivated deliberately, be careful while growing it. Because once you grow it in your garden, it starts multiplying. Common forget me not weed plant once get appropriate condition to grow, it starts self-seeding.

How to Control It?

Similar to the other two weeds, forget-me-not weed plants can also be eradicated easily by pulling them away from the root using your hands.

But this method is feasible only for a small amount of the weed plant. But to deal with large patches of weed, you must apply chemical control. Glyphosate-containing products work well to control forget-me-nots.

Also Read:- Lawn Weed Prevention: Causes, Types, and Solutions

4. Borage

Image Source: gardenerspath
Type: Borago Officinalis

Borage also belongs Boraginaceae family as same as the forget-me-not plants. This one is a summer weed plant that blooms in the summer. The flowers of the Borago weeds are star-shaped and bright blue.

The flowers contain black-purple stamens and a cone that protrudes from the center. The borage weed plants are tall plants that, when grown fully, touch the height of 3 feet.

Large oval or egg-shaped leaves can reach lengths of 30 cm and 20 cm. and have prickly fuzz covering them. The plant’s stems are a spiky greenish-grey color.

How to Control It?

Since borage’s a prolific self-seeing plant that proliferates and spreads throughout the garden, it becomes tough to control its spreading.

One of the best ways to deter weed garden is to cover your garden. You can cover your garden using cardboard, newspaper, or black landscaping fabric.

5. Blueweed

Image Source: education.mdc.mo
Type: Echium Vulgare

It is also known as Viper’s bugloss. The plant first originated in Europe and temperate Asia. The blooming period for the Blueweed plant is between May to September in North America.

Recognizing this weed plant can be a little complex as the flower growth is initially pink. But as the plant matures, the flower turns into a blue flower. The blooms have prominent protruding stamens and are funnel-shaped, growing on a spike with branches.

Blueweed grows up to a height of 3 feet tall. And it contains lanceolate leaves. Further, the plant has spines on the stem and leaves, much like a cactus.

How to Control It?

When dealing with small Viper’s bugloss plants, you must first plug it away from its root using your hands. But you must be careful here as this weed plant has cactus-like spines.

The hairy stems and foliage of the weed plant can cause rashes and skin irritation. To avoid so, we recommend you use gloves.

6. Carpet Bugleweed

Carpet Bugleweed
Image Source: thespruce
Type: Ajuga Reptans

It is a broadleaf perennial ground cover. With its growth, it develops an opaque mat of dark green leaves. Along with that, it forms breathtakingly beautiful dark blue flowers.

The blooming phase of this weed starts from May to mid-June. It spikes up to a length of 6 inches. In well-watered lawns, it can occasionally become invasive. But the weed is flexible and will thrive in only somewhat dry soil.

How to Control It?

You must maintain thick turf grass with appropriate fertilizer and nourishment to keep spiked speedwell at bay. You can also prevent them from developing by properly mulching your garden beds and regularly checking for weeds in the early stages of growth.

7. Spiked Speedwell

Spiked Speedwell
Image Source: etsy
Type: Veronica

Spiked Sleepwell is one of the most common weeds that you can find on your lawn. This weed is very prominent among the blue-colored weed because of its highly tiny flower.

However, there is a variety of speedwell blue-flowered weeds growing in the lawn that grows distinctive same blue flowers.

But as the name explains itself, spiked speedwell tiny, star-shaped flowers clustered around the end of the stem in a highly visible spike. However, as the name of the plant implies, spiked speedwell had a cluster of tiny, star-shaped flowers at the stem’s tip.

How to Control It?

Lawn maintenance can prevent Sleepwell from taking over, but we recommend you use herbicides to control its growth.

Two very prominent and effective herbicides are available easily in the market, and they are pre-emergent and post-emergent. The first is a preventative measure, and the second is an alternative if the speedwell is already beginning to grow.

8. Common Chicory

Common Chicory
Image Source: worldoffloweringplants
Type: Chicorium Intybus

This weed plant is easy to spot if growing in your backyard because of its distinctive, beautiful blue flower.

Its flower has many florists and blooms on the branched stem with a cluster of flowers numbered between 1-5. Common Chicory starts growing between June and the fall when the first frost arrives.

In the early phase of growth, it looks identical to a dandelion. Its maximum growth of it is up to 3-10 inches.

How to Control It?

To keep Chicory away, you must keep your turf grass thick with proper fertilization and nutrition. You can also resist it growing in your garden with proper mulching beds and a regular investigation for the weeds in the early phase of their growing up.

9. Common Blue Violet

Common Blue Violet
Image Source: plantsmap
Type: Viola Sororia

Common blue violet has comparatively small flowers, and its growth limits up to 4 inches long and 6 inches wide. The sprouting of leaves and flowers takes place from the stem.

The flowers with blue-violet color bloom slightly at the head of the leaves. If the atmosphere is cool, moist, and somewhat shaded, its color is dark green. But when the sunlight is available and the temperature is enough, its leaf turns yellowish green.

How to Control It?

In the spring, mowing the lawn prevents the common blue violet weed from growing on your lawn. If the infection has spread to your lawn, you can use herbicides.

Or, in the early stage of growth, when the flowers are very few, you can easily eradicate them using your hands.

10. Siberian Squill

Siberian Squill
Image Source: ifreebsd.ru
Type: Scilla Siberica

Looking identical to the blade of grass, the Siberian Squill grows its leaves looking more like a sword. The growth of the leave is from the base of the plant from where it points itself out.

This unique growth pattern of the leaves of this blue-flowered weed makes it easy to recognize. The growth is in the form of patches and grows by hiding low in the turf grasses.

How to Control it?

It’s tough to get rid of as they are self-seeding and spread vis bulbs. Therefore, if you catch it in its early growth phase, pull it away using your gloves.

If it has infected a sizable turf area, you must suffocate it using black plastic, layers of cardboard, or any other form of suppression.


Though blue flower weed gives an aesthetic look to the garden, many do not cause severe harm to the other plants in your garden in the short term. But in the future, the effect will be harmful.

What it does is it sucks out all the nutrients of the nutrients and moisture from the soil and leaves significantly less for your plant, which is not sufficient for the growth of plants. Therefore, it is advisable to take the cure for it before it infects your lawn.

Happy Gardening!

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