Perennial vegetables need help to survive cold winters
Perennial vegetables like asparagus or rhubarb need protection over the winter to help survive freezing temperatures. Asparagus is hardy down to zone 4 and needs a little care in the fall. When the ferns start to turn yellow to brown, or after the first frost, cut them back to about 2 inch stubs. This will help cut down on disease setting in over the winter. Apply about 2–3” of compost around the remaining plants and cover with a mulch such as rice straw to a depth of about 4–6”.
Rhubarb is a tough plant and only needs to be cut to the ground and covered with a 4–6” layer of compost.
Jerusalem artichokes can be if left in the ground until you are ready to eat them. However, if your ground freezes, you should dig up the remaining tubers and store in moist sand or soil in the garage or a shed (that stays above freezing but below 40°F).
To care for artichokes, check out our related article on Caring for Artichokes for more detail.