Species Heartleaf Arnica
bright-yellow flowers with yellow center, green leaves, stems, and grey branches

Heartleaf Arnica

Arnica cordifolia

Also Known As - Heartleaf Leopardbane
Heartleaf Arnica (Arnica cordifolia) is a perennial herbaceous plant native to the western United States. It grows to a height of 1-2 feet, producing bright yellow flowers in summer. The leaves are heart-shaped and toothed, resembling parsley. The plant also has distinctive gray-green, pinnately-divided leaves. It prefers full sun and moist soil, and is often found in montane meadows and forests. The plant has been used traditionally for its medicinal properties, and is especially useful for conditions such as rheumatism and indigestions. It is an attractive plant with colorful blossoms and foliage, and is suitable for both gardens and wildflower displays.

Watering:

Average

Propagation:

Division,Root Cutting,Seed Propagation,Layering Propagation,Stem Propagation

Hardiness Zone:

Flowers:

Yellow Flowers

Sun:

Sun, Partial Shade

Soil:

Sand, Loam

Leaf:

Yes

Leaf Color:

green

Growth Rate:

Low

Drought Tolerant:

Yes

Care Level:

Medium

watering

Heartleaf Arnica typically requires moderate watering, with 3-4 inches of water per week being suggested for optimal plant health. Water should be applied evenly, spread out over the course of the week as opposed to 1 large portion. Check the soil before watering to help determine how much water is needed. If the soil is generally moist or damp 1-2 inches of water should be enough. During hotter, drier weather, water may need to be increased. If the leaves are wilting or curling, the plant likely needs more water. Too much water can be just as harmful as too little, so make sure not to overwater.

sunlight

Heartleaf Arnica needs about 6 hours of direct sunlight per day when grown in the garden. The best time for providing sunlight to the plant is in the morning, from sunrise until mid-morning. During the midday hours, while direct sunlight is still beneficial, too much intense sunlight can be harmful and potentially cause leaf burn, so it's best to provide some shade with a canopy or similar structure at least for a few hours. To ensure ample sunlight, it’s best to plant in an area facing the southeast in the northern hemisphere or the northwest in the southern hemisphere. This plant species is also known to do well in partial shade, but in order to ensure healthy growth, the less shade provided, the better.

pruning

Heartleaf Arnica (Arnica cordifolia) can be pruned in the early spring just before new growth begins. Pruning should be done lightly and not all the way down to the ground as this can result in damage to the plant. Generally, it is best to remove any dead, diseased, or weak stems and flower stalks, and shape the plant as desired. Additionally, any crossing or bushy stems should be pruned to promote air circulation and sunlight penetration. Since Arnica heartleaf has a spreading habit, excess lateral branches can be trimmed to reduce sprawling. Overall, it is important not to remove more than 1/3 of the plant when pruning as excessive pruning can negatively impact the health of the plant.

Season

Fall
Winter
Spring
Summer
Sep
Oct
Nov
Dec
Jan
Feb
Mar
Apr
May
Jun
Jul
Aug
Starts Flowering

Heartleaf Arnica typically starts flowering in June.