First I want to encourage you not to give up on Mums. They really aren't too difficult, unless you are in full shade.

If you have the right conditions and good soil they usually come back. They prefer full sun and well drained soil. I don't cut them back in the fall. The dead stems help protect the crown during the winter by catching snow; snow helps insulate. After the plants are completely dormant and ground frozen, lay some cut pine boughs over top of the plant. This also helps insulate. Unless you live somewhere extremely cold, (which zone 5 is not) it isn't the winter that usually hurts them. It is the freezing and thawing cycles that often occur during the winter that causes the most damage. Pine boughs (other mulches also) and snow help prevent these conditions; this is referred to as 'heaving'. Heaving is when freezing and thawing causes the plant to be pushed up out of the ground.

If you don't have pine boughs yourself, go to a Christmas tree farm or sale lot and ask if they have a discard pile. You might be able to get some for free. Pine boughs are great for many perennials.

If you don't have well draining soil you can add organic matter in the form of compost or peat moss. Adding organic matter is always a good idea anyways, to any soil. Soil gets depleted and the organic matter helps replenish the soil. Just adding fertilzers doesn't improve soil.

For more information about composting do a 'search' on the 'Home' page.

In the spring you will see new growth starting; this is when you can remove the dead stems. Mums need to be divided after several years. Scroll down to the very first question on the 'Garden Question and Discussion' page and you will find a question about mums. Click on the replies for more maintenance information.

Hope this helps and you have success, Diane