Answer: Black Eyed Susans should be perennial in your garden so if you're losing them over the winter months, either the soil is remaining too wet or they need some additional winter protection. You can wait until the tops die down with the first hard frost, then cut away the dead stems and foliage and cover over the top of the plant with compost, dried leaves, or even pine boughs to protect the root system. In the spring brush the mulch material away and your plant should re-emerge.
Best wishes with your plants!
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