Leave Natural Bird Feeders
Consider leaving the last annual and perennial flowers and seed heads untrimmed this fall. Many are decorative under a layer of frost or light snow, and birds and other wildlife will feast on them long into the winter. The stems are still easy to remove in early spring once the weather has beaten them down.
Clean Out the Pond
Clear out all the leaves, twigs, and other seasonal debris. If you did not put netting over your pond, you will need to skim it and gently rake the bottom clean. For better water quality, also remove the faded foliage from lilies and other plants. Stop feeding the fish now, too, if you haven't already.
Prevent Deer Damage
Deer browse repeatedly by habit in the same places. If spray-on repellents don't work, you'll need to provide some barriers. Protect individual shrubs with wire mesh cages, protect tree trunks from antler rubbing with wire mesh cylinders, and consider installing a very tall fence or perhaps an electrified fence.
Pot Up Amaryllis
Plant amaryllis bulbs with the top third of the bulb above the soil; use a smallish pot about an inch wider than the bulb. Set it in a sunny location, keep the soil slightly moist, and wait for foliage and bloom stalks. Once the flowers begin to open, move the container to a slightly cooler location (60 degrees F is great) to help them last longer.
Mulch Root Veggies
Fall root crops, such as carrots, parsnips, and Jerusalem artichokes, can be left in the ground for harvest later. To take advantage of this natural storage space, mark the location and heap on a generous layer of mulch to prevent the ground from freezing solid before you are ready to dig them up.