I have a large pot in my apartment that I have been growing Thai chili peppers in for the last 5 years. They usually don't last more than a year, I pulverize a few peppers on top of the soil and the seeds sprout pretty quickly and the plant gets rather large when it gets enough sun. It's been a fun cycle but I want to switch to something more long term and was thinking of buying some weeping fig seeds. Will the years of sprinkling peppers into the soil (the peppers are very spicy) make the soil a hostile environment for other plants? Thank you so much for taking the time to read this!
The pepper does not make the soil spicy. If you have had the soil for five years, it is time to plant in new soil. Through the years the soil will have been depleted of nutrients, there may be a buildup of soluble salts if fertilizing regularly, etc.
Here is information on potting and repotting houseplants if you decide to buy a plant
Do a google search on germination of ficus benjamina for more information if you buy seed.