Today, I noticed a spider plant 'vine' sticking through one of my jade plants. I have tons of variegated spider plants in many pots that are all outdoors. I figured someone moved a potted variegated spider plant and that one of the 'vines' poked through my jade plant.
When I went to inspect, it turned out to be a 'vine' sticking out of one of the green grass-like plants! After double-checking, I realized that these plants were spider plants!
The spider plants are growing in several jade plant pots.
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Here's a couple spider plants in a jade plant pot.
I asked online and found out that when seeds are grown from variegated spider plants, the seedlings are green. I guess when I had the jade plants beneath the flowerboxes that the spider plants were growing in, the seeds fell into the pots. This is really a pleasant surprise.