Spider plants have jumped from pots into the yard, and are spreading fairly rapidly across the shady portions, near the south fence. Will these become a problem in the future, or can I regard them as a relatively benign, drought-tolerant ground cover?
Specifically, I'm wondering if they will choke out other plants, deplete the soil, and/or be very difficult to dig out should I decide to remove them someday.
Spider plants in nature ARE ground covers ... Mother Nature never made anything such as a house plant ..... they are very easy to care for and to maintain ... just snip off the pups when they have enough root.. to control where you want them to grow and use the pups for hanging baskets or start a new bed somewhere else .... they do not harm the soil ... I love the spider plants as a ground cover ... I have them in the ground and in pots .... and it works out great in the ground because you can make as many hanging baskets as you want .... I sell some of mine .. it makes you a few extra bucks ... they are very easy to dig up .. I use a pitch fork to pull them out of the ground ...I am a Florida State certified Horticulturist who has been in the Business for 30 yrs ... hopes this helps you out ..they do prefer morning sun to partial shade .. they do not like the hot afternoon sun ... and they are somewhat Arid ... so you don't have to worry about rushing out to water them ...
Having done a bit of research, your USDA Zone is 10a, which means this plant should survive very well outdoors, as you've discovered. It's also chosen the best spot - light shade, because it burns in hot sun. It is useful for ground cover in shade situations, and is reasonably drought resistant, but will suffer from extended drought. It's a good plant to use, particularly in walls or raised areas where its 'babies' and leaves trail attractively, but is considered quite aggressive, in that it spreads easily. It is not, though, difficult to dig up and remove.
Regarding depletion of soil, they don't absorb any more nutrients than any other plant would.
To sum up, if it's not checked by unusual cold, waterlogging at the roots or extended drought, you may need to dig out parts periodically to keep it where you want it.
