For the best results indoors, place your plant in an area with bright filtered light. If you are in the northern hemisphere, a windowsill on the north side of your home is ideal. (In the southern hemisphere, a southern window is good.) Another good option is an eastern or western window, with either a sheer curtain in place or with the plant placed about a foot away.
Asparagus Fern loves to spend time outdoors in the summer but be sure to start with a shady spot and move slowly to a brighter area. Keep your plant in its pot if you don’t want it to take over your garden; Asparagus Fern is a vigorous grower and will spread like wildfire once it escapes. Though only hardy to USDA Zone 9, some people report that this plant will come back again as far as Zone 6 in sheltered areas. Keep that in mind because once this plant is in your garden, nothing but a killing frost will keep it from coming back again.
When your Asparagus Fern is safely contained in a pot you will have to water it every now and then. It is important not to over-water this one, so water only when the potting mix is dry. Watering can be decreased in the winter months, but be watchful of leaves dropping off. This is an indication that the plant needs more water. Misting the plant occasionally can help until it seems to be recovering, but is not typically necessary.
There are a couple of choices for fertilization; if you have other foliage houseplants you can carry over your regimen to this plant. If not, try using a slow-release fertilizer in the spring when you begin to see a fresh flush of growth. Alternatively, you can use a water-soluble fertilizer at every other watering diluted to half-strength.
Asparagus Fern is typically propagated by division or from seed. Division should be done when the plant is actively growing, so preferably in the spring or early summer. Keep freshly divided sections of the plant from drying out. Seeds sprout readily in about 3 to 4 weeks.
The ASPCA lists Asparagus Fern as toxic to cats and dogs. The plant can also cause dermatitis, or skin irritation, if handled too much. The plant may produce small red berries that, when ingested, can cause stomach discomfort.