The asparagus fern isn’t exactly a common houseplant, but it’s attractive with feathery, light foliage and can be successfully grown indoors. In warmer regions, the fern can be easily adapted to outdoor culture, where it sometimes grows like a creeper and can even become invasive. Indoors, the key to a robust asparagus fern is to keep the plant bushy and dense so its lace-like foliage forms an attractive mound.
The most popular asparagus fern is the Asparagus aethiopicus. There are also a few other varieties sometimes seen in cultivation, including Asparagus asparagoides, which has ovoid pseudo-leaves, and Asparagus setaceus, which has very fine needles.
The asparagus fern thrives in dappled shade, although it can be acclimated to more light. Avoid direct, bright sunlight and try to maintain a warm temperature (around 70 F) and not dip below 55 F for too long. Keeping an asparagus fern hydrated takes a little effort. This plant thrives on humidity. Indoor growing conditions can often be dry, especially due to winter heat. Mist the plant daily, focusing on the arching stems. If the plant appears to be turning brown and drooping, it likely needs more water. While the asparagus fern can dry out to the point of appearing dead, it likely isn't. Warmer, humid air and daily misting will help revive it. Asparagus ferns should be planted in loose, well-draining potting soil.
This plant's “leaves” are actually tiny branchlets called cladophylls that are flat and look like leaves. Mature plants become woody and can develop sharp spines on the branches, so take caution while trimming older specimens and wear gardening gloves if you plan to prune an older plant. If you have a shady porch outside or a greenhouse, these plants enjoying being outdoors over the summer and will likely respond with abundant growth.
Repotting and Propagation
Like many ferns, this variety doesn’t mind being slightly pot-bound and can go up to two years before repotting. For the most successful repotting, divide the plant in big clumps, and be sure to take multiple underground roots when dividing. Place the divided plants into similar sized pots to retain the tight growth habit. Asparagus ferns do not need large pots, as they are slow indoor spreaders. When this plant is content in its location, it can produce small flowers and berries. These berries can be planted and will propagate the plant.
Asparagus Fern Precautions
If consumed, the berries of the asparagus fern plant may cause gastrointestinal issues, such as diarrhea, vomiting, and abdominal pain. If the berries come in contact with the skin, they may cause a rash at the point of contact. Additionally, asparagus fern is toxic to domestic cats and dogs. Take caution if you have this plant in your house with small children and pets, especially if it if producing berries. In warm, humid climates, this fern can spread rapidly when planted outdoors. In Florida and Hawaii, asparagus fern has been declared a weed because of its invasive nature.