Q.hostas
I planted a hosta garden several years ago and have continued to add different varieties. All of my hostas did well for years. Recently, the growth of the oldest ones have dwindled, though the newer ones continue to thrive. What could be the problem? Slugs are not the issue. Please help!

What changes are you seeing in your Hosta?
Hosta often slow in growth and dividing the plants can help spread your collection and rejuvenate a plant.
Hosta can suffer more serious issues and the link below will have more information for you.
https://www.gardeningknowhow.com/ornamental/foliage/hosta/hosta-problems.htm
https://www.gardeningknowhow.com/ornamental/foliage/hosta/transplanting-hostas.htm
https://www.gardeningknowhow.com/ornamental/foliage/hosta/hosta-plant-diseases.htm