Trumpet vine is aggressive and probably was a water and nutrient hog!
Potting soil does wear out. Pretty quickly in warmer areas. I replace
1/4 to 1/3 of the soil in my outdoor plants yearly. Just take a little soil out (do not throw away, add to manure or compost to refresh) and put in new soil or compost. Ever so often maybe every 4 to 5 years, I change out all the soil. Many blessings for your continued success!
