The citronella plant, known for its lemony scent, is popular for deterring mosquitoes. Gardeners often wonder if it’s an annual or perennial, returning each year or needing replanting. Understanding its lifespan is key to successful cultivation.
Understanding Plant Lifecycles
Plants are typically categorized into three main lifecycles: annuals, biennials, and perennials. An annual plant completes its life cycle in a single growing season, from seed to seed, then dies, like marigolds or zinnias. These plants are often chosen for seasonal color and rapid growth.
Biennial plants require two growing seasons to complete their life cycle. During their first year, they typically produce vegetative growth like leaves and roots, storing energy. In their second year, they flower, set seed, and then die, with examples including foxgloves and sweet William.
Perennial plants live for more than two years, returning each year from the same rootstock. Their foliage may die back in winter, but new growth emerges in spring. Hostas and peonies are common examples, providing consistent beauty for many seasons.
The Citronella Plant’s Classification
The plant commonly marketed as a “citronella plant” is botanically known as Pelargonium citrosum, a type of scented geranium. This plant is classified as a tender perennial, meaning it can live for multiple years but cannot withstand freezing temperatures. Its ability to survive winter depends heavily on the local climate.
In warmer regions (USDA Hardiness Zones 9 through 11), Pelargonium citrosum thrives as a perennial, returning yearly. In colder climates where temperatures drop below freezing, it is typically treated as an annual, as it won’t survive winter outdoors without protection.
Extending Your Citronella Plant’s Life
For gardeners in colder climates who wish to preserve their Pelargonium citrosum plants, overwintering indoors is a reliable strategy. Before outdoor temperatures consistently drop to 45°F, bring potted plants inside. Prune back any dead or damaged foliage and stems by about one-third, making cuts just above a leaf node.
Once indoors, place the plant in a location with bright, filtered light, such as a south-facing window. Reduce watering significantly, allowing the soil to dry out slightly between waterings to prevent root issues. Less frequent irrigation is generally better, as overwatering is a common mistake for indoor plants during winter.
Another method to ensure new plants for the following season is taking cuttings in late summer or early fall. Softwood cuttings, 3 to 5 inches long, can be rooted in water or a well-draining potting mix. This allows propagation of new plants, ensuring a supply for the next season even if the parent plant does not survive the winter.