if regularly deheaded months and even into a years. I have a couple that are about 18 months old, though they are struggling a bit now.

Hungry plants, though. They need rich soil in the ground, or regular feeding when in pots.

I have one that's 3 years old and healthy.

Keep in mind that pansies don't like the summer heat and are classic cool weather plants. They bloom in Spring, go dormant over the summer and bloom again in the fall. If you forget them over the summer, they won't come back.

Pansies are a classic cool weather flower, used in most places as an annual. In some warmer and moderate climates, like parts of California, gardeners can grow them year round. ... They will bloom well until the heat of summer, at which time the plants will wilt and sag and stop producing flowers.

https://www.gardeningknowhow.com/ornamental/flowers/pansy/summertime-pansies-and-heat.htm