Identifying Common Garden Weeds with Heart-Shaped Leaves

As a gardener, few things are more frustrating than weeds invading your flower beds or vegetable garden Weeds compete with your plants for water, nutrients, and sunlight They can quickly take over your yard or garden if left unchecked. When identifying and removing weeds, a key characteristic to look for is the shape of the leaves. Several common garden weeds have distinctive heart-shaped leaves.

In this article, we’ll look at the most prevalent weeds with heart-shaped or heart-like leaves that pop up in home gardens. Identifying these pesky intruders will help you control them more effectively.

What Causes Heart-Shaped Leaves in Weeds?

The heart shape of leaves in certain weeds occurs due to the arrangement of veins in the leaf blade. Veins deliver water and nutrients to the leaf cells and provide structural support. In heart-shaped leaves, the veins run from the base of the leaf and converge at the tip to form the heart shape. This shape is scientifically known as cordate.

The heart shape is thought to maximize the surface area of the leaf to capture more sunlight for photosynthesis. Having more veins also improves water transport and leaf cooling. The indented base of heart-shaped leaves channels rainwater down towards the roots as well. Overall, this leaf shape gives weeds several advantages for growth and survival.

Common Garden Weeds with Heart-Shaped Leaves

Here are some of the most prevalent heart-leaf weeds found in home gardens:

1. Wood Sorrel (Oxalis sp.)

This perennial weed has clover-like, heart-shaped leaves and spreads rapidly through seeds and bulbs. It’s recognizable by its small yellow flowers with 5 petals. There are several varieties including creeping wood sorrel (Oxalis corniculata) and violet wood sorrel (Oxalis violacea).

2. Velvetleaf (Abutilon theophrasti)

Also called Indian mallow or butterprint, this tall annual weed reaches up to 5 feet and can quickly shade out garden plants. Its large, heart-shaped, velvety leaves are up to 10 inches wide. Yellow hibiscus-like flowers bloom in summer.

3. Morning Glory (Ipomoea sp.)

While some morning glories are grown as ornamentals, certain species are aggressive weeds with twining vines and heart-shaped leaves. Common morning glory (Ipomoea purpurea) and ivy leaf morning glory (Ipomoea hederacea) are especially problematic in gardens.

4. Henbit (Lamium amplexicaule)

This low-growing annual has square stems and ragged-edged, heart-shaped leaves. It blooms profusely with purple flowers in spring. A major lawn and garden weed, henbit spreads rapidly by seeds.

5. Buttercup (Ranunculus sp.)

Several buttercup species produce long-stemmed, glossy yellow flowers above heart-shaped foliage. Persian buttercup (Ranunculus asiaticus) and creeping buttercup (Ranunculus repens) are common buttercup weeds. All plant parts are toxic.

6. Speedwell (Veronica sp.)

There are over 200 Veronica speedwell species, many considered weeds. Nearly all have petite heart-shaped or rounded leaves in pairs. Tiny blue, purple, or white flowers bloom on short spikes. Common speedwell (Veronica officinalis) is most prevalent.

7. Betony (Stachys sp.)

This perennial has square, grooved stems and textured heart-shaped leaves with scalloped edges. Dense pink or purple flower spikes up to 3 feet tall make it obvious. Great betony (Stachys officinalis) and hedge nettle (Stachys sylvatica) are common weeds.

8. Spurge (Euphorbia sp.)

Numerous spurge weeds emerge in gardens, including petty spurge (Euphorbia peplus) and prostrate spurge (Euphorbia humistrata). They have oval leaves with pointed tips in opposite pairs and heart-shaped bases where they attach to stems. Tiny cup-shaped green flowers form. Milky sap oozes when stems are broken.

9. Geranium (Erodium sp. and Geranium sp.)

Both true geraniums (Geranium sp.) and cranesbills (Erodium sp.) produce pretty 5-petaled flowers above mounded, lobed, heart-shaped foliage. While they make nice ornamentals, some spread aggressively. Herb Robert (Geranium robertianum) is notoriously weedy.

10. Smartweeds (Persicaria sp. and Polygonum sp.)

These summer and fall emerging annuals have thin, heart-shaped or lance-shaped leaves. Small pink or white flowers grow in spiky clusters. Pennsylvania smartweed (Persicaria pensylvanica) and ladysthumb (Polygonum persicaria) are two weedy smartweeds.

Controlling Heart-Leaf Garden Weeds

The key to controlling heart-leaf weeds is identifying and removing them promptly before they spread seeds. Here are some effective control methods:

• Hand pull small weeds, grasping low and removing the entire root. Cover with mulch to block light.

• For larger weeds, use a spade or weed popper tool to uproot them.

• Mow down weeds regularly with a lawn mower set at a high height.

• Use corn gluten as an organic pre-emergent herbicide to prevent seed germination.

• For severe infestations, spot treat with a post-emergent herbicide containing glyphosate or 2,4-D.

• Solarize weed-prone areas by covering the soil with plastic sheeting in summer to bake weeds and seeds.

• Improve your garden soil and select vigorous plants that can outcompete weeds.

Identifying heart-shaped weeds will give you a leg up in your battle against garden weeds. Deal with them promptly and thoroughly to prevent their spread. With quick action, you can get back to enjoying a lush, healthy garden.

Common Heart-Shaped Leaf Weeds at a Glance

Weed Name – Wood Sorrel

Key Features – Yellow, 5-petaled flowers, clover-like leaves

Control – Hand pull, improve garden drainage

Weed Name – Velvetleaf

Key Features – Large velvety leaves, yellow hibiscus flowers

Control – Mulch heavily, hand pull before flowering

Weed Name – Morning Glory

Key Features – Vining, twining stems, trumpet flowers

Control – Remove seedlings promptly before vining

Weed Name – Henbit

Key Features – Purple flowers, square stems, ragged leaves

Control – Mow regularly, use pre-emergent herbicide

Weed Name – Buttercup

Key Features – Glossy yellow flowers, toxic sap

Control – Hand pull before flowering and seed set

Weed Name – Smartweed

Key Features – Spiky pink/white flowers, lance-shaped leaves

Control – Pull young plants, avoid overwatering

10 Heart-Shaped Leaf Weeds to Watch For

1. Wood Sorrel
2. Velvetleaf
3. Morning Glory
4. Henbit
5. Buttercup
6. Speedwell
7. Betony
8. Spurge
9. Geranium
10. Smartweed

Garden weeds with heart-shaped leaves encompass several different plant families. But they share common growth habits – spreading aggressively by seeds and sometimes underground stems or bulbs. Identifying heart-leaf weeds while they are small is key to controlling them. Employ a combination of manual removal, mowing, mulching, and improving your garden soil and plant coverage. With diligence, you can gain the upper hand on pesky heart-leaf weeds.