Other than containing their spread, caring for these plants is relatively easy. Just be sure they are getting sufficient water, and fertilize annually if you don’t already have rich soil. Common butterbur plants generally don’t have any major problems with pests or diseases, though slugs eating holes in the leaves sometimes can be an issue. Slugs can be controlled through both chemical pesticides and natural solutions. Likewise, strong winds can damage the leaves, so aim to situate your plants in a somewhat sheltered location.
Light
Shady conditions are ideal for common butterbur plants, though they also can grow in partial sun. In fact, the variegated varieties tend to achieve the best foliage coloration in partial sun. However, too much sunlight can cause the leaves to wilt and/or burn. If this occurs and you are able to relocate your plant to a shadier spot, the damaged leaves eventually will fall off and be replaced with fresh foliage.
Soil
Common butterbur isn’t overly picky about its soil type. It can grow in sandy soil as long as it gets enough water. But a loamy or clay soil that retains more water is best. A slightly acidic to neutral soil pH is ideal.
Water
These plants thrive in evenly moist soil, and they can handle occasional flooding. Water whenever the soil begins to dry out about an inch or two down. And in hot weather, be sure to give the plants a little extra water.
Temperature and Humidity
Common butterbur tolerates the hot and cold temperatures of its growing zones well, as long as it has the right amount of water, shade, and wind protection. It prefers moderate to high humidity levels and will likely need more frequent watering in dry climates.
Fertilizer
An organically rich soil is ideal for common butterbur. At the time of planting, mix some compost into the soil to enrich it. If you already have fertile soil, you might just need to keep adding a layer of compost in the spring to ensure healthy growth. To further boost common butterbur’s growth, use a fertilizer with a ratio of 16-4-8 for nitrogen, phosphorus, and potassium, following label instructions.
Butterbur Varieties
There are several species and varieties of butterbur that slightly differ in appearance, including:
Petasites japonicus: Commonly known as butterbur or fuki, this species is similar in size to common butterbur and also has large leaves. Its blooms are yellowish-white.Petasites albus: Also known as white butterbur, this plant features clusters of white blooms in the spring.Petasites pyrenaicus (or Petasites fragrans): Also referred to as winter heliotrope, this species sports mauve-pink flowers that have a light vanilla scent.
