Pictures Of Common Lawn Weeds In Hawaii

Hawaii’s tropical environment supports lawn weeds like chamberbitter and carpetgrass that grow year-round. If you’re searching for pictures of common lawn weeds in hawaii, you’ve come to the right place. This guide will help you identify and manage these persistent plants with clear images and practical steps.

Weeds thrive in Hawaii’s warm, wet climate. They compete with your grass for water, nutrients, and sunlight. Knowing what you’re dealing with is the first step to a healthier lawn.

Below you’ll find detailed descriptions and visual cues for the most frequent lawn invaders in the islands. Use these to match what you see in your yard.

Chamberbitter (Phyllanthus Urinaria)

Also called gripeweed or shatterstone, chamberbitter is a small, upright weed with tiny leaves arranged like mimosa. It produces small green flowers and round seed capsules that explode when touched.

Leaves: Compound, with many small leaflets
Height: 6 to 18 inches
Flowers: Tiny, greenish, hanging from leaf axils
Seed pods: Round, green, and explosive

This weed spreads quickly by seed. It loves disturbed soil and thin lawns. Pull it before seeds mature to prevent spreading.

Carpetgrass (Axonopus Compressus)

Carpetgrass forms a dense, low-growing mat that chokes out desirable turf. It has broad, flat blades and a creeping growth habit. Its seed heads are tall, thin, and finger-like.

Blades: Broad, light green, blunt-tipped
Growth: Creeping stolons that root at nodes
Seed heads: Two to three finger-like spikes
Appearance: Forms a thick, carpet-like cover

Carpetgrass thrives in wet, shady areas. It’s often mistaken for St. Augustine grass but has thinner blades. Hand removal is tough because of its deep roots.

Hilo Grass (Paspalum Conjugatum)

Hilo grass is a perennial weed with spreading stolons and flat, hairy leaf sheaths. It produces paired seed spikes that look like a V. It’s common in lawns and pastures across Hawaii.

Leaves: Flat, hairy, with a prominent midrib
Stems: Creeping, rooting at nodes
Seed heads: Two spikes forming a V shape
Height: 6 to 24 inches

This weed tolerates both sun and shade. It spreads aggressively through stolons and seeds. Regular mowing helps control it, but herbicides may be needed.

Broadleaf Plantain (Plantago Major)

Broadleaf plantain has large, oval leaves with prominent veins. It forms a rosette close to the ground. Its flower stalks are tall, thin, and bear small greenish flowers.

Leaves: Broad, oval, with parallel veins
Growth: Rosette form, low to ground
Flower stalks: Tall, slender, with tiny flowers
Roots: Thick taproot

This weed thrives in compacted soil. It’s a sign your lawn needs aeration. Hand pulling is effective if you get the entire taproot.

Dollarweed (Hydrocotyle Umbellata)

Dollarweed has round, shiny leaves that resemble small coins. It grows in moist, shady areas. Its stems are thin and creeping, and it produces small white flowers.

Leaves: Round, scalloped edges, waxy
Size: Leaves about 1 to 2 inches across
Flowers: Small, white, in clusters
Habitat: Wet, poorly drained soil

Dollarweed is often mistaken for a desirable ground cover. It spreads by seeds and rhizomes. Improving drainage is key to control.

Spurge (Euphorbia Spp.)

Spurge is a low-growing weed with small, oval leaves arranged opposite each other. It produces a milky sap when broken. Its stems are reddish and often lie flat on the ground.

Leaves: Small, oval, with fine teeth
Sap: White, milky, can irritate skin
Stems: Reddish, prostrate
Flowers: Tiny, inconspicuous

Spurge thrives in hot, dry areas. It spreads by seeds. Hand pull carefully to avoid skin contact with the sap.

Nutgrass (Cyperus Rotundus)

Nutgrass, or purple nutsedge, is not a true grass. It has triangular stems and shiny, dark green leaves. It produces underground tubers called nutlets that make it hard to control.

Stems: Triangular in cross-section
Leaves: Shiny, dark green, V-shaped
Seed heads: Purple-brown, umbrella-like
Roots: Rhizomes with small tubers

This weed is a nightmare for many Hawaii lawns. It spreads rapidly through tubers. Hand pulling often breaks the tubers, making it worse. Herbicides are usually required.

Creeping Charlie (Glechoma Hederacea)

Creeping Charlie has round, scalloped leaves and square stems. It forms a dense mat that smothers grass. It produces small, purple flowers in spring.

Leaves: Round, scalloped edges, aromatic
Stems: Square, creeping, rooting at nodes
Flowers: Small, purple, trumpet-shaped
Growth: Forms thick ground cover

This weed thrives in shade and moist soil. It spreads by stolons. Improving sunlight and air circulation helps control it.

Bermuda Grass (Cynodon Dactylon)

Bermuda grass is a common lawn grass but can become a weed in other turf types. It has fine, gray-green blades and aggressive stolons and rhizomes. It spreads quickly into flower beds.

Blades: Fine, gray-green, short
Growth: Stolons above ground, rhizomes below
Seed heads: Finger-like spikes, 3 to 5
Appearance: Forms dense, low turf

Bermuda grass is drought-tolerant and invasive. It’s hard to remove without herbicides. Regular mowing keeps it in check.

Kikuyu Grass (Pennisetum Clandestinum)

Kikuyu grass is a coarse, fast-growing weed that forms thick mats. It has broad, dark green leaves and aggressive runners. It’s often used as pasture grass but invades lawns.

Leaves: Broad, dark green, hairy
Stems: Thick, creeping stolons
Seed heads: Hidden in leaf sheaths
Growth: Extremely aggressive

This weed can take over a lawn quickly. It’s difficult to control due to its deep root system. Frequent mowing and herbicides are needed.

How To Identify Weeds Using Pictures

Matching what you see to pictures is the easiest way to identify weeds. Here’s a step-by-step process.

Take a clear photo of the weed from above and from the side
Note the leaf shape, size, and arrangement
Look at the stem: is it round, square, or triangular?
Check for flowers or seed heads
Compare your photo to the pictures in this guide

If you’re still unsure, take a sample to your local garden center. They can help identify it and recommend control methods.

Common Mistakes When Identifying Weeds

Confusing young weeds with desirable plants
Ignoring the root system
Not checking the stem shape
Assuming all broadleaf weeds are the same

Take your time. Accurate identification saves you time and money on the wrong treatment.

Prevention Tips For Hawaii Lawns

Preventing weeds is easier than removing them. Here are practical steps for Hawaii’s climate.

Mow at the correct height for your grass type
Water deeply but infrequently to encourage deep roots
Fertilize regularly to keep grass thick
Aerate compacted soil annually
Fill bare spots with grass seed or sod

A thick, healthy lawn is the best defense against weeds. Weeds can’t compete with dense grass.

Mowing Tips For Weed Prevention

Mowing too short stresses grass and allows weeds to take hold. Keep your mower blades sharp. Never cut more than one-third of the grass height at once.

Bermuda grass: 1 to 2 inches
St. Augustine grass: 2.5 to 4 inches
Zoysia grass: 1 to 2 inches
Centipede grass: 1.5 to 2 inches

Adjust your mowing height based on the season. Raise it during hot, dry periods.

Control Methods For Common Weeds

Different weeds require different control methods. Here’s a breakdown.

Hand Pulling

Best for small infestations or weeds with shallow roots. Pull after rain when soil is soft. Get the entire root to prevent regrowth.

Chamberbitter: Easy to pull when young
Broadleaf plantain: Requires full taproot removal
Spurge: Wear gloves to avoid sap

Dispose of pulled weeds in the trash, not compost. Seeds can survive composting.

Herbicides

Use herbicides as a last resort. Choose products labeled for your grass type. Follow instructions carefully.

Pre-emergents: Apply in spring and fall to prevent seeds
Post-emergents: Apply to actively growing weeds
Selective herbicides: Kill weeds without harming grass
Non-selective herbicides: Kill everything, use carefully

Always spot-treat rather than broadcasting over the entire lawn. This reduces chemical use.

Natural Alternatives

Some gardeners prefer non-chemical methods. These can be effective with patience.

Boiling water: Pour on individual weeds
Vinegar: Use horticultural vinegar for best results
Corn gluten meal: Natural pre-emergent
Solarization: Cover soil with clear plastic to kill weeds

Natural methods may require repeated applications. They work best on small areas.

Seasonal Weed Management In Hawaii

Hawaii’s mild climate means weeds grow year-round. But there are seasonal patterns.

Wet season (November to March): More weed growth, especially grasses
Dry season (April to October): Slower growth, but drought-tolerant weeds thrive
Transition periods: Best time for pre-emergent application

Adjust your weed control efforts based on the season. Focus on prevention during wet months.

Wet Season Strategies

Weeds explode during Hawaii’s rainy season. Stay on top of them.

Mow more frequently to prevent seed heads
Check for new weeds weekly
Apply pre-emergent before heavy rains
Improve drainage to reduce weed-friendly conditions

Don’t let weeds get established. Early intervention saves work later.

Dry Season Strategies

Weeds like spurge and nutgrass thrive in dry conditions. Focus on these.

Water deeply to encourage grass over weeds
Hand pull drought-tolerant weeds
Apply mulch to bare areas
Monitor for nutgrass, which is active in dry heat

Dry season is a good time to repair bare spots. Grass will establish without competition.

Frequently Asked Questions

What is the most common lawn weed in Hawaii?

Chamberbitter and carpetgrass are among the most common. They adapt well to Hawaii’s climate and spread quickly.

How can I get rid of nutgrass in my Hawaii lawn?

Nutgrass is difficult to control. Use a selective herbicide containing halosulfuron or sulfentrazone. Apply when the weed is actively growing. Repeat applications are often needed.

Are there any weeds in Hawaii that are poisonous to pets?

Yes, spurge produces a milky sap that can irritate skin and cause digestive issues if ingested. Keep pets away from treated areas until herbicides dry.

Can I use vinegar to kill lawn weeds in Hawaii?

Household vinegar is weak. Use horticultural vinegar (20% acetic acid) for better results. It works best on young weeds and in sunny weather. Be careful, as it can also kill grass.

How often should I apply pre-emergent herbicide in Hawaii?

Apply pre-emergent twice a year, in early spring and early fall. This targets the main weed germination periods. Follow product instructions for your specific grass type.

Final Tips For A Weed-Free Lawn

Consistency is key. Check your lawn weekly for new weeds. Remove them early before they spread. Keep your grass healthy with proper mowing, watering, and fertilizing.

Learn to identify weeds using pictures
Act quickly when you see a problem
Use the right control method for each weed
Don’t forget to maintain your lawn tools

With these strategies, you can enjoy a lush, green lawn that’s the envy of your neighborhood. Remember, a little effort each week prevents big problems later.