Overview
Veronica arvensis L., commonly known as corn speedwell, is an annual herbaceous plant in the Plantaginaceae family. This plant is native to Europe and Western Asia but has been introduced to other parts of the world, including North and South America. It is a well-known and widely distributed plant in the temperate regions of the world, where it grows as a weed in various habitats such as agricultural land, disturbed areas, and open fields.
Appearance
Corn speedwell is a small plant that grows up to 30 cm in height. The stem is slender, erect, and branched. The leaves are opposite, elliptical, and toothed edges. The flowers are small and blue-purple, with five petals, two stamens and are arranged in a spike-like inflorescence. The fruits are small and flattened capsules that contain several small seeds. This fast-growing and prolific plant can produce several generations in one year under suitable conditions.
Common Names
Besides corn speedwell, Veronica arvensis is also known by other common names such as Wall Speedwell, Rock Speedwell, Creeping Speedwell, and Whitlow Grass.
Uses
Corn speedwell is not an economically important plant but has various medicinal properties. Different parts of the plant, such as leaves, flowers, and roots, are used as a traditional remedy for several ailments such as respiratory tract infections, diarrhea, bronchitis, and fever. The plant is a rich source of antioxidants, flavonoids, tannins, and alkaloids. In addition, Veronica arvensis is used as a culinary herb, and the young leaves are eaten raw or cooked.
Light Requirements
Veronica arvensis L. requires full sun to partial shade for optimal growth. It grows well in areas with plenty of direct sunlight, but it can also tolerate light shade. The plant may require more shade in hot climates to prevent leaf scorching and wilting.
Temperature Requirements
This plant is tolerant of a range of temperatures as it grows in a variety of conditions. However, the optimal growth temperature range is between 13 to 25°C (55 to 77°F). Veronica arvensis L. can grow in cooler temperatures, but growth may become slow. The plant can also tolerate occasional frosts, but prolonged freezing temperatures could end up killing the plant.
Soil Requirements
Veronica arvensis L. can grow in a variety of soil types but prefers those that are moist and well-draining. The plant is not too picky about pH but tends to grow best in slightly acidic to neutral soils. Ideal soil pH range would be between 6.0 to 7.5. This plant is also known to thrive in soil with high organic matter content. It can tolerate salty soil conditions, but not excessively salty or waterlogged soils.
Cultivation Methods
Veronica arvensis, also known as corn speedwell, is an annual plant that can be grown in most soil types and light conditions. It prefers well-drained soil and can tolerate partial shade but thrives in full sunlight. Sow seeds directly in the ground early in the spring or fall. It's important to thin the seedlings to avoid overcrowding, which can lead to disease and stunted growth.
Watering Needs
Corn speedwell requires regular watering to keep the soil moist but not overly wet. Water deeply 1-2 times a week, but adjust the watering frequency based on weather conditions and soil type. Avoid watering the foliage and instead water at the base of the plant to prevent foliar diseases.
Fertilization
While not particularly nutrient-demanding, Veronica arvensis can benefit from a balanced fertilizer application, such as a 10-10-10 slow-release fertilizer, once per month during the growing season. Be careful not to over-fertilize as this can cause vegetative growth at the expense of flowers.
Pruning
Corn speedwell is a low-growing plant that generally does not require pruning, other than the occasional removal of spent flowers to encourage continued blooming. However, if the plant becomes too leggy or begins to flop, it can be trimmed back by a third to encourage bushier growth.
Propagation of Veronica arvensis L.
Veronica arvensis L., commonly known as corn speedwell, is a rapidly spreading, low-growing annual or perennial plant that produces attractive blue flowers. This plant is commonly found in agricultural fields, lawns, gardens, and disturbed areas. Propagation of Veronica arvensis L. can be done by using seeds or cuttings.
Propagation by seeds
The easiest way to propagate Veronica arvensis L. is by using seeds. The seeds of this plant can be sown directly into the soil in the spring, or they can be started indoors several weeks before the last frost. Here are the steps to follow:
- Collect the seeds from mature Veronica arvensis L. plants in the late summer or fall.
- Prepare a seed bed by loosening the soil and removing any weeds.
- Sow the seeds thinly and cover them with a thin layer of soil.
- Water the seeds gently and keep the soil moist until the seedlings emerge, which usually takes 7-14 days.
- Thin the seedlings to 8-12 inches apart when they are large enough to handle.
Propagation by cuttings
Propagation of Veronica arvensis L. can also be done by using cuttings. This method is usually used for perennial types. Here are the steps to follow:
- Select a healthy stem from the parent plant that is at least 4 inches long and has several leaves.
- Cut the stem below a node using a sharp, sterilized knife.
- Remove the lower leaves from the stem, leaving only two or three leaves at the top.
- Dip the cut end of the stem into rooting hormone powder.
- Insert the stem into a well-draining potting mix or soil, taking care not to damage the rooting hormone powder.
- Water the cutting gently and cover it with a plastic bag or a cloche to maintain humidity.
- Place the pot in a warm, bright location, but avoid direct sunlight.
- Check the cutting regularly and keep the soil moist, but not waterlogged.
- After four to six weeks, gently tug on the stem to check for resistance, which indicates that roots have formed.
- Transplant the rooted cutting into a larger pot or the garden soil, taking care not to disturb the roots.
Disease and Pest Management for Veronica arvensis L.
Veronica arvensis L., commonly known as field speedwell or bird's-eye speedwell, is a hardy annual weed that is native to Europe but has spread to other parts of the world. It grows well in disturbed areas, agricultural fields, and has adapted to a wide range of soil types and climatic conditions. However, it is not immune to diseases and pests that can negatively impact its growth and yield. As such, managing these diseases and pests is imperative for optimal growth and yield of the plant.
Diseases
Field speedwell can fall prey to several diseases, including powdery mildew, rust, and verticillium wilt. Powdery mildew appears as a white, powdery coating on the leaves and stems of the plant, reducing photosynthesis and causing stunted growth. Rust, on the other hand, appears as reddish-brown pustules on the leaves, stunting growth, and reducing yield.
Verticillium wilt presents as the yellowing of leaves that progress to brown, wilting, and death. It is a soil-borne disease that attacks the root system and moves to the rest of the plant.
To manage these diseases, it is essential to maintain proper sanitation, crop rotation, and the application of fungicides. Since powdery mildew and rust thrive in humid conditions, it is important to keep the foliage dry and spray fungicides to prevent their spread. Crop rotation and the use of resistant varieties can also help control the spread of verticillium wilt.
Pests
Several pests attack the field speedwell, and these include spider mites, cutworms, and slugs. Spider mites suck the life out of the plant leaving behind a yellowish, wilted appearance of leaves. Cutworms feed on the stem of the plant, causing damage and eventually death. Slugs feed on leaves, leaving behind holes and damaging the foliage.
To manage these pests, it is important to use cultural control practices, such as mulching and removing plant debris, to reduce the population of the pests. Additionally, the use of insecticides can also help prevent pest infestation. However, it is important to follow the safety guidelines and regulations when using insecticides to prevent environmental damage.
Conclusion
Proper disease and pest management practices are essential in promoting optimal growth and yield of Veronica arvensis L. Regular monitoring of the plant is important to identify and manage any potential diseases and pests before they cause significant damage. Maintaining proper sanitation, crop rotation, and the use of insecticides and fungicides should be part of the integrated pest management program to protect the plant from disease and pest attack.
