In case you ever wondered, the asparagus “ferns” you often see are, in fact, really asparagus, but they are not edible (as far as I know). A couple of ornamental favorites include:
Asparagus Densiflorous – The basic asparagus fern. A good hanging basket and pot plant, it grows from spring until the first hard freeze. It can take some freezing weather, but it is not nearly as cold-hardy as the edible asparagus. Some people try to save favorite or special plants from year-to-year, but if you keep them in the house, they will drop needles everywhere. To prevent this problem on a plant that must be indoors, give it good light and use a weak fertilizer like seaweed, terra cycle or Great Big Plants at regular or lower-than-normal rates. Also take care not to stress your plants from too much or too little watering. To avoid these problems, you may want to try passive systems such as self-watering pots or soil water crystals can help prevent this from happening.
Asparagus setaceus – This is a very unusual climbing asparagus (up to 10 feet) with attractive white flowers and black berries. It also has a few thorns, so be careful where you place this plant in the house. The only place it can grow permanently outdoors is in the Deep South (zone 9 and warmer).