Creating a butterfly garden requires providing a sustained food source for every stage of their life cycle. Herbs provide both the nectar adult insects require and the specific foliage needed by their young. These aromatic plants are easy to grow and integrate seamlessly into an existing landscape, transforming a traditional herb plot into a vibrant ecosystem. By selecting herbs that cater to the unique needs of these winged visitors, you can ensure a consistent presence of butterflies in your outdoor space.
Nectar Sources: Herbs That Feed Adult Butterflies
Adult butterflies rely on high-sugar nectar to fuel their flight and reproduction, favoring flowers that allow for easy access. Many common culinary herbs, when allowed to flower, produce dense clusters of small blossoms ideal for this purpose. The tiny, clustered flowers of herbs like oregano and marjoram offer a concentrated nectar supply that minimizes the energy butterflies expend flying from bloom to bloom.
Lavender is a highly effective attractant, with English lavender (Lavandula angustifolia) being particularly favored by many species. Its dense flower spikes provide a substantial and long-lasting source of nectar, blooming from early summer until the first frost. Similarly, the mint family, including catmint (Nepeta) and hyssop (Hyssopus officinalis), produces numerous small, nectar-rich flowers over an extended period.
Allowing herbs such as basil and chives to flower is crucial for attracting butterflies. Chives produce striking, spherical flower heads that act as convenient landing platforms for various species. Borage, with its distinctive blue, star-shaped blossoms, is also an excellent nectar source, offering a continuous supply of sustenance. Butterflies prefer flowers arranged in clusters or those with a flat surface, such as the umbels of fennel or the broad heads of calendula, which provide a stable place to perch while feeding.
Host Plants: Herbs Essential for Butterfly Reproduction
While nectar plants feed the adults, host plants are the specific food source for the butterfly’s larval stage, the caterpillar. Female butterflies will only lay their eggs on the foliage of particular plant species that their young are adapted to eat. Providing these host herbs is the most effective strategy for ensuring butterflies remain in your garden long-term, moving from transient visitors to permanent residents.
Several common herbs belonging to the carrot family (Apiaceae) are host plants for the Black Swallowtail butterfly (Papilio polyxenes). This includes dill, parsley, and fennel, which serve as the sole diet for their caterpillars. Gardeners must anticipate that this foliage will be heavily consumed, so planting extra is a practical measure to share the harvest.
Other herbs serve as host plants for different species, further diversifying your garden’s appeal. Rue (Ruta graveolens) is another host for the Black Swallowtail, while mint varieties can support the caterpillars of the Gray Hairstreak butterfly (Strymon melinus). Lemon balm (Melissa officinalis) is a host for the White Peacock butterfly.
Strategic Placement and Maintenance for Optimal Attraction
To maximize attraction, butterflies are drawn to large, dense groupings of flowers, so planting herbs in masses rather than single specimens creates a more visible and appealing target. Positioning these mass plantings in sunny areas is necessary, as butterflies are cold-blooded and require warmth to fly and feed efficiently. A location that receives six or more hours of direct sunlight daily will encourage both robust herb growth and butterfly activity.
The use of pesticides should be avoided in a butterfly garden, particularly on host plants, as the larvae are highly susceptible to chemical harm. Even Bacillus thuringiensis (Bt), a natural biological control, is lethal to butterfly caterpillars. A healthier approach is to tolerate some insect damage and focus on an integrated pest management strategy.
Maintenance techniques can extend the period of attraction throughout the season. Allowing herbs to flower naturally, instead of pinching off buds for culinary purposes, is the primary way to provide nectar. Creating a “puddling station”—a shallow dish of moist sand or mud—provides butterflies with necessary minerals and hydration. Finally, providing vertical shelter, such as allowing some taller herbs to remain uncut, offers resting places and protection from wind and predators.