Overview and Common Names
Achillea borealis Bong. ssp. arenicola (Heller) Keck, commonly referred to as beach yarrow, is a herbaceous perennial plant belonging to the Asteraceae family. The plant is native to North America and can be found growing in coastal areas from Alaska to California, as well as in the Rocky Mountains.
Appearance
Beach yarrow typically grows to be around 10-25 cm tall and has a clumping habit. Its leaves are fern-like and are usually around 5 cm long. The plant produces an inflorescence of small, white flowers that are arranged in clusters that can reach up to 10 cm in diameter. The flowers bloom from June to September.
Uses
The leaves and flowers of beach yarrow have been used by Indigenous peoples of North America for their medicinal properties. The plant contains tannins, which make it astringent, as well as essential oils, which give it antiseptic and anti-inflammatory properties. The plant has been used to treat a variety of ailments, including digestive issues, skin conditions, and respiratory problems. Additionally, the plant's dried leaves and flowers have been used as a natural insect repellent.
Light Requirements
Achillea borealis Bong. ssp. arenicola (Heller) Keck prefers full sun to partial shade. It requires at least 6 hours of direct sunlight every day to thrive. In shaded areas, the plant tends to grow tall and lean towards the light source. Therefore, it is best to plant it in an area with sufficient sunlight.
Temperature Requirements
The plant is native to arctic and alpine regions, which implies that it can tolerate low temperatures. It grows well in cold and harsh climates found in regions such as tundra, subalpine meadows, and rocky slopes. Temperatures between 10-20°C are optimal for growth, but temperatures as low as -20°C do not affect the plant's growth and survival.
Soil Requirements
The plant can grow in a wide range of soil types, from well-drained sandy soils to heavy clays, as long as they are not waterlogged. The soil pH should range from slightly acidic to slightly alkaline. The recommended pH range is between 6.0 and 7.5. It is essential to ensure that the soil is rich in organic matter and nutrients such as nitrogen, phosphorus, and potassium. The addition of organic matter through the use of compost or well-rotted manure improves soil structure and nutrient availability.
Cultivation
Achillea borealis Bong. ssp. arenicola (Heller) Keck requires well-drained soil that is not too rich in nutrients. Ideally, the plant should be grown in full sun. This plant is hardy to zones 4-9. If grown in a container, ensure that it is sufficiently large to accommodate the plant's root system.
Watering Needs
While Achillea borealis Bong. ssp. arenicola (Heller) Keck prefers not to be overwatered, it still requires consistent moisture. Ensure that the plant is watered deeply and that the soil is allowed to dry slightly between waterings. If the soil is too dry, the plant may not bloom as abundantly.
Fertilization
Achillea borealis Bong. ssp. arenicola (Heller) Keck does not require a lot of fertilizer. Fertilization should be done in the early spring, just as the plant is beginning to emerge from dormancy. Organic fertilizers such as compost and manure are preferred over synthetic fertilizers.
Pruning
Pruning is not necessary for Achillea borealis Bong. ssp. arenicola (Heller) Keck, as it is a relatively low-maintenance plant. However, the occasional deadheading of spent blooms will help promote further blooming and keep the plant looking tidy. If the plant becomes too leggy, it can be pruned back by up to one-third of its height in the late spring.
Propagation of Achillea borealis Bong. ssp. arenicola (Heller) Keck
Achillea borealis Bong. ssp. arenicola (Heller) Keck, also known as the sand yarrow, is a perennial plant that typically grows in sandy or gravelly soil in areas of high elevation. Propagation of this plant can be done through either seed or division.
Propagation by Seed
The most common method of propagation for Achillea borealis is through seed. The seeds should be sown in the fall, as they require a period of cold stratification before germinating. It is recommended to plant the seeds directly in the desired location, as transplanting can hinder growth and establishment. The seeds should be covered with a thin layer of soil and kept moist until germination occurs.
Propagation by Division
Propagation of Achillea borealis can also be done through division. This method is best done in the spring or fall. To divide the plant, carefully dig it up and separate the root system into smaller sections, each with its own stem and foliage. Replant the divisions in their new location and make sure to keep the soil consistently moist until the plant becomes established.
Whether propagating through seed or division, it is important to keep the soil moist and provide adequate sunlight for the plant's growth and development. With proper care, Achillea borealis can produce beautiful, long-lasting clusters of flowers that attract a variety of pollinators.
Disease Management for Achillea borealis Bong. ssp. arenicola (Heller) Keck
While Achillea borealis Bong. ssp. arenicola (Heller) Keck is generally a disease-resistant plant, it can occasionally be affected by fungal diseases. The most common diseases that affect this plant are leaf spot and powdery mildew. Leaf spot presents as circular spots with dark edges and light centers on the leaves, while powdery mildew is a white powdery substance on the leaves.
To manage fungal diseases on Achillea borealis Bong. ssp. arenicola (Heller) Keck, it is important to take preventive measures. Avoid planting in areas with poor air circulation and do not water late in the afternoon or evening to prevent excess moisture. Fungicides can also be used, but it is important to follow instructions carefully and not overuse them.
Pest Management for Achillea borealis Bong. ssp. arenicola (Heller) Keck
Achillea borealis Bong. ssp. arenicola (Heller) Keck is also relatively pest-resistant, but it can occasionally be affected by pests such as aphids and spider mites. Aphids are small, pear-shaped insects that suck the sap out of the plant and can cause stunted growth and deformities. Spider mites are tiny arachnids that feed on the undersides of leaves, causing yellowing and webbing.
To manage pests on Achillea borealis Bong. ssp. arenicola (Heller) Keck, it is important to monitor the plant regularly and catch infestations early. Natural predators such as ladybugs and lacewings can be introduced to control aphids, and spider mites can be managed by washing the plant with a strong stream of water or using a miticide. It is important to follow instructions carefully when using any pesticide or miticide.
