Is Asparagus Fern an Annual or a Perennial?

Asparagus fern is a sprawling shrub native to coastal southeastern South Africa. It is not a true fern, despite its common name. Instead, it belongs to either the asparagus family (Asparagaceae) or the lily family (Liliaceae), which includes plants like amaryllis, daylilies, hosta, and tulips. It is in the genus Asparagus, which includes the edible A. officinalis, along with about 300 other species. There are a few different names for this species, but most sources refer to it as Asparagus densiflorus. aethiopicus, A. sprengeri, and Protasparagus densiflorus are also used as well by some. This tender evergreen perennial has bright green, ferny leaves that are often used as a houseplant or outdoor ornamental plant. In mild climates, it is planted outdoors as a groundcover or in containers. It is hardy in zones 9-11 but the roots will often survive to zone 7 if protected. In more temperate climates, it is used as a seasonal annual or container plant. For its native range, the asparagus fern lives in shady, sandy places like coastal dunes, open rocky areas, and woods. When it gets out of farms, it usually grows along shady roadsides and invading forests or rainforests, where it pushes out native plants and stops native species from coming back. It is considered an invasive weed in some locations, including Florida, Texas and Hawaii in the US. Asparagus fern produces long, upright or trailing, branching stems sparsely covered with sharp, stiff spines in the axils. The round stems can be up to 6 feet long, are green to brown, and have a small depression running the length of them. What appear to be leaves are actually leaf-like cladodes (short, flattened stems that look and function like leaves). These needle-like “leaves” arise in groups of four to eight from the nodes along the stem. The true leaves are barely visible scales near the base of the cladodes. Plants have a dense fibrous root system as well as creeping rhizomes and numerous fleshy white bulbous tubers. Small white or pinkish-white flowers grow in long clusters (racemes) along the stems from spring to fall on fully grown plants that get enough light. Each flower has six tepals (3 petals and 3 sepals similar in appearance). The flowers are small and not very noticeable, even though they smell nice. Plants that grow in mild climates often don’t bloom. Plants are dioecious. If pollinated, female flowers are followed by small round berries up to ¼ inch in diameter. The green fruits mature to a glossy red and each contains one to three black seeds. Many birds are attracted to the fruits and are responsible for unintended seed dispersal in mild climates. The berries can cause dermatitis on the skin and stomach problems if eaten. Cats and dogs should not eat them. This plant does best in full sun or light shade. Plants that get full sun are more compact and dense than plants that get shade. It grows best in moist, organically rich soils, but it can handle almost any situation and is pretty resistant to drought once it’s established. Asparagus fern is valued as an ornamental for its bright green, arching stems and airy foliage. Its fine leaves look fluffy or soft, and they look great when mixed with plants that have medium to coarse-textured leaves or very big leaves to create a nice contrast in texture. You can plant it in the ground with other annuals as a bedding plant in cold places after the last frost. This plant works well as a filler in pots, especially hanging baskets or big urns where the delicate leaves can hang down. It has a tropical feel when combined with elephant ears, canna lilies and hibiscus. The foliage can also be incorporated as a filler with cut flowers in arrangements. Asparagus fern is a great houseplant for novice gardeners as it doesn’t require any special care. It grows well in bright direct light or bright indirect light; the brighter the light, the faster it grows. It can handle being ignored for a while because its tuberous roots store water. It grows best when it has steady moisture, but in the winter, plants should be kept drier and no fertilizer should be used. The foliage will yellow and drop if the soil is too dry or there isn’t enough light. Remove any stems that are old or yellow from the base of the plant. You can also trim back the ends of stems to keep the shape of the plant. In the spring trim out old growth and begin fertilizing monthly for lush new growth. These plants can quickly outgrow their containers, so need frequent repotting to keep them growing vigorously. The roots are also quite strong and can break pots, so larger, thicker containers may be desireable. Repotting is best done in early spring before new growth starts. Seasonally, indoor plants can be moved outside (but should be brought back inside before frost). However, they should get used to the brighter light outside before being moved to a spot in full sun. This plant doesn’t have many pests, both inside and outside. But aphids, mealybugs, spider mites, and whiteflies may show up from time to time. Asparagus fern can be propagated from seed and division. Seeds will germinate in 3-4 weeks at room temperature. Scarify the seeds and soak in water for a day before planting to hasten germination. Plants can be separated into smaller pieces or the tubers will regenerate plants. It is best to divide these tough plants in the spring, but you can do it almost any time of the year. The two most common varieties are ‘Sprengeri’ and ‘Meyeri’. The second type, which is often called “foxtail asparagus fern,” has stems that stand up straighter and denser leaves that look like the tail of a fluffy animal spreading out from the plant’s center. This variety looks great as a tall focal point in the ground or in a pot with lower plants all around it. It doesn’t make seeds as quickly as the species, so it doesn’t have as much of a chance of spreading in mild climates. ‘Cwebe’ has graceful, upright, arching stems and copper-colored new growth. It does best in light shade. ‘Sprengeri Nanus’ and ’Sprengeri Compacta’ are more compact forms. – Susan Mahr, University of Wisconsin – Madison.

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Everything You Need to Know About Asparagus Ferns | Plant Encyclopedia | Better Homes & Gardens

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