Introduction

Japanese blood grass (Imperata cylindrica) is a striking ornamental grass known for its vibrant red foliage. While it can add a touch of color to gardens, it’s essential to be aware of its invasive potential and take steps to control its spread.

Characteristics

• Botanical Name: Imperata cylindrica
• Common Name: Japanese blood grass, cogongrass
• Plant Type: Perennial
• Mature Size: 1 – 2 ft.
• Sun Exposure: Full
• Soil Type: Moist but well-drained
• Soil pH: Acidic, alkaline (6.5-7.5)
• Hardiness Zones: 5, 6, 7, 8, 9

Cultivation

Light

Japanese blood grass thrives in full sun, receiving at least six hours of direct sunlight daily. In warmer climates, some afternoon shade is acceptable.

Soil

Provide your blood grass with moist, well-drained soil. It grows well in sandy soils and even tolerates coastal garden conditions.

Water

Japanese blood grass is a vigorous grower that prefers moist soils. However, it can also tolerate drought conditions. Water the plant only as necessary to prevent the browning of foliage.

Temperature and Humidity

This grass grows well in a wide range of temperatures. In warmer climates, it can spread and displace other plants with its rhizomes. Both humid and dry conditions are tolerated.

Fertilizer

Japanese blood grass does not require fertilizer to thrive. Excessive nutrients may cause the grass to grow aggressively.

Invasive Potential

While the red form of Japanese blood grass is technically not invasive, it can easily revert to the green form, which is considered one of the most invasive weeds in the world. Some states have declared the green form a noxious weed due to its ability to spread rapidly and outcompete native plants.

Control Methods

• Choose sterile cultivars: Plant named, sterile cultivars such as ‘Red Baron’ or ‘Rubra.’ These grasses have few or no flowers and spread slowly by rhizomes.
• Container culture: Growing Japanese blood grass in containers can help prevent it from spreading into the surrounding area.
• Physical removal: Remove any plants that revert to green to prevent them from spreading.

Propagation

Japanese blood grass is easy to propagate by division. Cut into the plant with a spade in the spring or fall when growth is most active. Divide the plant into as many small divisions as needed, as they will grow and mature rapidly.

Overwintering

Japanese blood grass requires no special care for overwintering. The colors stay vibrant through cooler temperatures, and it can be left alone and cut back in early spring.

Common Problems

Japanese blood grass is not typically bothered by pests or diseases. However, it’s important to remove any plants that revert to green to prevent them from becoming invasive.

Frequently Asked Questions

• Can Japanese blood grass grow indoors?

Container culture is best for regions at risk of the weedy potential of Japanese blood grass. Combine it with trailing plants or flowers.

• What is an alternative to Japanese blood grass?

Purple fountain grass offers a similar look with its dark purple stems and bronzy plumes. It is a tender perennial often treated as an annual.

• How do I grow Japanese blood grass from seeds?

The desirable named cultivars do not produce viable seeds. It is not recommended to grow seeds of the invasive species type.

• How do I repot Japanese blood grass?

Repot the grass in the spring or fall as needed when plants become crowded with spreading rhizomes. Use any type of potting soil or container.

• How do I overwinter Japanese blood grass?

No special care is needed for overwintering. The colors remain vibrant, and the grass can be left alone and cut back in early spring.

Identification

Common tansy (Tanacetum vulgare) is a highly invasive perennial plant that is easily recognizable by its distinctive features. It boasts dark green, fern-like foliage with golden, button-like flower clusters that bloom atop stems reaching up to 5 feet in height. This aromatic plant was once prized for its medicinal properties but has since become a major threat to North American ecosystems.

Invasiveness

Common tansy is a prolific seed producer and a vigorous spreader via its rhizomatous roots. It forms dense stands that can quickly overtake native vegetation, reducing biodiversity and degrading wildlife habitat. The plant’s toxicity to humans, cows, and horses further exacerbates its impact on the environment.

Removal

If common tansy has established itself on your property, it is crucial to eliminate it promptly. Individual plants or small patches can be removed manually by digging them out with a shovel, ensuring the removal of all roots. However, this method is only effective for small infestations.

For larger infestations, a broad-spectrum herbicide may be necessary. Target the plants to be removed and follow the instructions carefully to minimize environmental impact. Mowing before applying herbicide can weaken the plants and reduce the amount of herbicide required.

Prevention

To prevent common tansy from spreading, it is essential to remove plants before they set seed. This can be done by cutting or pulling them out before or during the flowering period in the summer. If removal occurs after seed heads have developed, new plants may germinate the following year.

Distinguishing Common Tansy from Tansy Ragwort

Common tansy can be differentiated from tansy ragwort (Senecio jacobea) by its unique flower structure. While common tansy has yellow, button-like blooms, tansy ragwort has daisy-like flowers with 13 ray petals and yellow centers. Both plants are considered noxious invasive weeds.

Frequently Asked Questions

• What are the uses of tansy flower?

Traditionally, tansy flower was used in various medicinal applications. However, scientific evidence supporting its medicinal properties is limited, and it is primarily considered toxic.

• Should I plant tansy to keep mosquitoes away?

Research suggests that distilled oil from common tansy can effectively repel mosquitoes. However, it is important to note that the plant itself may pose a health risk to humans and animals.

• What are tansy flowers symbolic of?

Tansy is associated with immortality, protection, health, and resistance. The word “tansy” originates from the Greek word “athanasia,” which means immortality.

• What is the best time of year to remove common tansy?

The optimal time to remove common tansy is before or during the flowering period in the summer, before it sets seed.

• What are the natural enemies of common tansy?

Currently, there are no known natural enemies that effectively control common tansy.

Introduction

Japanese pachysandra (Pachysandra terminalis) is a versatile evergreen perennial that thrives in challenging growing conditions, making it an ideal choice for groundcover in shady, dry areas. Its dense foliage and aggressive growth habit provide excellent weed suppression and add year-round interest to landscapes. However, its invasive potential in some regions requires careful management.

Characteristics of Japanese Pachysandra

• Evergreen Perennial: Retains its foliage throughout the year, turning slightly yellow in winter.
• Groundcover: Forms a dense mat that suppresses weeds and erosion.
• Drought-Tolerant: Tolerates dry spells and requires minimal watering once established.
• Shade-Tolerant: Thrives in partial to full shade, making it suitable for shady areas under trees or structures.
• Deer Resistant: Unpalatable to deer, providing protection from browsing damage.

Benefits of Japanese Pachysandra

Japanese pachysandra offers several benefits as a groundcover:

• Landscaping Problem Solver: It solves common landscaping issues such as weed control, shade tolerance, and drought tolerance.
• Low Maintenance: Requires minimal care once established, saving time and effort.
• Aesthetic Appeal: Its dark-green, leathery leaves add texture and interest to shady areas.

Limitations of Japanese Pachysandra

Despite its many benefits, Japanese pachysandra has some limitations:

• Invasive Potential: In some areas, it can become invasive, spreading aggressively via rhizomes and runners.
• Dense Growth: Its dense foliage can lead to fungal diseases if proper air circulation is not maintained.

Types of Japanese Pachysandra

Several cultivars of Japanese pachysandra are available, each with unique characteristics:

• Allegheny Spurge (Pachysandra procumbens): Native to the United States, it grows less aggressively than Japanese pachysandra.
• Pachysandra terminalis ‘Green Carpet’: A compact cultivar with shiny dark green leaves.
• Pachysandra terminalis ‘Green Sheen’: Known for its glossy foliage.
• Pachysandra terminalis ‘Variegata’: Features irregular creamy white mottling along the edges of its leaves.

Care and Maintenance

Japanese pachysandra is relatively low-maintenance, but proper care is essential to prevent problems and maintain its health.

Planting:

• Plant in well-drained soil with a pH of 5.5 to 6.5.
• Choose a location with partial to full shade.
• Dig a hole twice the width of the root ball and plant at the same depth as the original container.

Watering:

• Water deeply after planting until the soil is saturated.
• Once established, water only during prolonged dry spells.

Fertilization:

• Fertilization is not necessary for Japanese pachysandra.

Pruning:

• Pruning is not essential, but thinning out dense patches can promote air circulation and prevent fungal diseases.

Division:

• Propagate Japanese pachysandra by dividing clumps in the spring.
• Dig up a clump and cut it into smaller sections with a sharp knife.
• Replant the divisions at the same depth as the original plant.

Potting:

• Growing Japanese pachysandra in pots is an effective way to control its spread.
• Use a pot with drainage holes and well-draining potting mix.
• Water regularly, as soil in pots dries out faster than in the ground.

Overwintering:

• Japanese pachysandra is winter-hardy down to zone 3.
• No special winter protection is required in cold climates.

Common Pests and Diseases

Japanese pachysandra is generally pest-resistant, but it is susceptible to leaf blight, caused by fungal infections. To prevent disease, avoid overwatering and remove fallen leaves that can trap moisture around the plant.

Comparison with Other Groundcovers

Japanese pachysandra is often compared to other groundcovers for shade, such as Vinca and sweet woodruff.

• Vinca (Vinca minor): A vine-like groundcover with blue flowers. It is also deer-resistant but considered invasive in some areas.
• Sweet Woodruff (Galium odoratum): A fragrant groundcover with lance-shaped leaves. It is deer-resistant but dies back in the winter and becomes dormant during the summer heat.

Additional Tips

• Choose a cultivar of Japanese pachysandra that suits your specific needs and growing conditions.
• Thin out dense growth regularly to prevent fungal diseases and improve air circulation.
• Avoid overwatering to prevent leaf blight.
• Monitor plants for signs of invasiveness and take steps to control their spread if necessary.

Identification

Yellow wood sorrel (Oxalis stricta) is a common weed that resembles clover. Its leaves are heart-shaped and radiate from a central point like fingers from a palm. The stems, branches, and leaf stalks have fine hairs.

Wood sorrel has a bright green color and produces small, yellow, five-petaled flowers from mid-spring to fall. The flowers are about 1/2 inch in diameter. The plant typically grows up to 20 inches tall and forms thick clumps.

Invasiveness and Spread

Yellow wood sorrel is considered an invasive plant in some areas, such as Kentucky. It spreads rapidly through horizontal stems (runners) and seeds that take root where they touch the soil.

The seed pods can hold up to 5,000 seeds, giving the plant ample opportunities to overtake gardens and other areas. Additionally, the seeds can be dispersed by wind, animals, and clothing, facilitating its spread.

Removal

Yellow wood sorrel can be removed by hand or using chemical methods.

Hand Removal

To remove the plant manually, dig it out or pull it up by the roots, ensuring to remove as much of the root system as possible. The roots are extensive and can resprout if left behind.

Chemical Removal

Glyphosate (Roundup) is an effective chemical solution for killing yellow wood sorrel, including its roots. It is a broad-spectrum herbicide, so care should be taken to avoid harming other plants.

For lawns, post-emergent herbicides containing triclopyr (cool-season turfgrass) or fluroxypyr (warm-season turfgrass) can be used to target wood sorrel without affecting the grass.

Prevention

Preventing yellow wood sorrel from establishing in the first place is crucial. Some effective methods include:

• Maintaining a Healthy Lawn: A thick, healthy lawn can outcompete wood sorrel for resources. Seed or sod any bare spots to prevent the weed from taking hold.
• Mulching Garden Beds: Mulch helps suppress weed growth by blocking sunlight. Use a two- to three-inch layer of organic mulch to prevent wood sorrel from germinating.
• Diligent Inspection: Regularly inspect your lawn and garden beds for signs of wood sorrel. Remove any plants as soon as they appear to prevent seed production.
• Herbicide Application: Post-emergent herbicides can be used to control existing wood sorrel and prevent its spread. Apply them in the late spring when the weeds are actively growing and before they produce seeds.

Distinguishing Yellow Wood Sorrel from Clover

Yellow wood sorrel is often confused with red or white clover, but there are key differences:

• Leaf Shape: Wood sorrel has heart-shaped leaves, while clover leaves are oval-shaped.
• Flower Color: Wood sorrel has bright yellow flowers, while white clover has white flowers and red clover has pink flowers.

Additional Information

• Edible Uses: All parts of yellow wood sorrel are edible and have a tangy flavor. It can be added to salads or used to make teas or other beverages.
• Toxicity: Yellow wood sorrel contains oxalic acid, which can be toxic to cats, dogs, and livestock in large amounts.
• Misidentification: Wood sorrel is sometimes mislabeled and sold as shamrock during St. Patrick’s Day season.

What is a Weed?

Weeds are plants that are considered undesirable or harmful in a particular location or context. They are often invasive and spread aggressively, competing with other plants for resources such as water, nutrients, and sunlight. Weeds can also harbor pests and diseases, making them a nuisance in gardens, lawns, and other managed landscapes.

Identification and Characteristics of Weeds

Identifying weeds can be challenging, as they vary greatly in appearance and growth habits. However, some common characteristics of weeds include:

• Growing in undesired locations
• Rapid growth and spread
• Invasive root systems (such as rhizomes)
• Production of abundant seeds
• Tolerance to adverse conditions

Weed Removal Methods

There are numerous methods for removing weeds, ranging from organic to chemical approaches. The most effective method depends on the type of weed and the specific situation.

Organic Weed Removal Methods

• Boiling Water: Pouring boiling water directly onto weeds can kill them, especially annual weeds with shallow roots.
• Salt: Mixing salt into water and applying it to weeds can dehydrate and kill them. However, salt can also harm soil health, so use it sparingly.
• Hand-Pulling: Removing weeds by hand is a labor-intensive but effective method. Ensure you remove the entire root system to prevent regrowth.

Chemical Weed Removal Methods

• Herbicides: Chemical herbicides are effective at killing weeds, but they can also harm beneficial plants and soil organisms. Use herbicides carefully and according to the manufacturer’s instructions.
• Preemergent Herbicides: These herbicides prevent weed seeds from germinating.
• Postemergent Herbicides: These herbicides kill weeds that have already emerged.

Invasive Plants and Control

Invasive plants are non-native species that spread aggressively and can harm native plant populations. Some invasive plants are also considered weeds. Controlling invasive plants is crucial for protecting native ecosystems.

• Deadheading: Removing flowers from invasive plants prevents them from producing seeds and spreading.
• Bamboo Barrier: Erecting a sturdy plastic barrier in the soil can contain the spread of invasive plants that spread via rhizomes (underground shoots).

Weed Control Without Chemicals

• Cultural Practices: Promoting healthy soil and plant growth through proper watering, fertilization, and mulching can help prevent weed infestations.
• Native Plants: Planting native plants that are adapted to the local climate and soil conditions can help crowd out weeds and reduce their spread.
• Integrated Pest Management (IPM): IPM involves using a combination of methods, including organic and chemical approaches, to control weeds while minimizing environmental impact.

Tips for Optimal Weed Control

• Early Detection and Removal: Identifying and removing weeds early on is essential for preventing their spread.
• Regular Maintenance: Mowing lawns, trimming hedges, and weeding regularly can help keep weeds in check.
• Use Caution with Herbicides: Only use herbicides as a last resort and follow the manufacturer’s instructions carefully.
• Promote Soil Health: Healthy soil promotes healthy plants that are more resistant to weeds.
• Consider Native Plants: Native plants provide numerous benefits, including weed suppression and support for local wildlife.

Overview

The squirting cucumber, also known as the exploding cucumber, is a unique and fascinating plant that draws attention with its explosive method of seed dispersal. Belonging to the genus Ecballium, it is a perennial vine characterized by its prickly fruits that burst open when ripe or disturbed, shooting mucilage-covered seeds up to 20 feet away.

Characteristics

Squirting cucumber is a fast-growing plant with wrinkled, bristly leaves and yellow bell-shaped flowers. It typically reaches a height of 12-18 inches and a width of 1-3 feet. The plant contains elaterium, a compound with medicinal properties when refined, but highly toxic in its unrefined form. Its “cucumber” fruits are decidedly non-edible.

Toxicity

It is crucial to note the toxic nature of squirting cucumber. The unrefined form of elaterium can cause digestive upset, diarrhea, hemorrhaging, kidney problems, and even death in large doses. Therefore, it is essential to wear protective gear when handling the plant and to keep it out of reach of children and pets.

Invasive Potential

Squirting cucumber is considered an invasive plant in many regions due to its prolific seed dispersal. Its creeping vines can spread rapidly, and its explosive fruits can contribute to the emergence of new plants far from the parent plant. Caution is advised if choosing to grow this plant, especially in areas where it is known to be invasive.

Growth Requirements

Squirting cucumber thrives in full sun and well-drained soil. It tolerates poor soil conditions and a wide range of soil pH levels. Its average water needs make it relatively low-maintenance, and it can withstand short periods of drought.

Propagation

Propagation of squirting cucumber is typically achieved through volunteer plants that emerge from seeds dispersed by the explosive fruits. These seedlings can be carefully transplanted to desired locations in the spring. Alternatively, seeds can be directly sown in the garden after the last frost.

Care

Squirting cucumber requires minimal care. It does not require feeding unless the soil is extremely barren. Common pests and diseases can be addressed with horticultural oil or spray fungicide.

Uses

Despite its toxicity and invasive potential, squirting cucumber has some limited uses in the landscape. It can be grown as a summer ground cover for sunny, dry areas, or planted to disguise the base of fences. It can also be trained to grow on supporting structures, providing a unique and eye-catching addition to gardens.

Removal

If the toxicity or invasiveness of squirting cucumber becomes a concern, it can be easily removed. Wear proper protective gear and carefully pull out the plant, discarding it in a sealed bag. Removal is best done early in the growing season before the fruits ripen.

Additional Information

• Historical Medicinal Uses: Squirting cucumber has been historically used in folk medicine as a remedy for dropsy, but its use is no longer recommended due to its potential for severe side effects.

• Alternative Ground Cover Options: For those seeking a less invasive and showy ground cover, consider other options such as Chinese lantern, chaste tree, or burning bush.

Conclusion

The squirting cucumber is a fascinating and unique plant, but its toxicity and invasive potential must be carefully considered before cultivation. With proper precautions and management, it can provide a distinctive addition to gardens while respecting its potential risks.