Dying artichokes can result from planting seedlings when the weather is still too cold, or failing to protect them in the winter. Lack of new growth, or new growth that dies back, is the obvious clue that they haven't survived the winter. The same is true for newly planted artichoke seedlings which turn brown and wither. Ideally, the plants should have about 100 frost free days each year to survive. Don't plant young artichokes until all possibility of frost has passed, in early spring. As winter approaches each year, cut artichokes to about 1 foot in height, then set a wooden or cardboard box over the crown, mounding a 24-inch layer of straw or leaves on and around the box.
When artichokes drop foliage and fail to produce buds at the height of summer, they are dying because of heat. If you are gardening in a region in which summers are too hot, artichokes risk risk die-back. They can also fail to resprout the following year if they don't get enough cool fall and winter days to allow them to go into the dormant stage they need. After the growing season ends, cut stems back all the way to the soil line and rake mulch away from the base of the plants. This method will give the ground has a chance to cool after the growing season. During the growing season, keep artichoke plants adequately watered. While it's fine to let the ground dry out between watering sessions, don't let more than a day or two of dry soil happen.
Artichokes can't survive if they aren't given the nutrients they need. When the plants are dying of poor nourishment, they may exhibit yellow or falling foliage, purple-red stems or spots on the foliage. Infertile soils also prevent artichoke plants from growing beyond the seedling stage, Like most plants, they rely on adequate amounts of nitrogen, phosphorus and potassium. Too much nitrogen, however, will result in more foliage than fewer edible buds. A 2 to 3-cup portion of 5-10-10 twice a year will provide adequate nutrients for an artichoke patch that is about 50 square feet. Sprinkle the plant food into the soil adjacent to the plants, then lightly work it into the top 3 to 6 inches of soil. Spring and fall are the best times to feed the artichoke patch.
A number of pests can cause artichokes to die if the attacks are serious enough. Insect pests that threaten the plants include aphids. Their damage includes the sticky substance they secrete, which can sometimes lead to sooty mold disease. At worst, the aphids can rob artichokes of all plant sap, while the disease they spread can kill plants by blocking all sunlight. Prevent the possibility of your artichokes being felled by sooty mold or loss of plant sap by regularly hosing aphids off your plants. If your artichokes seem to be dying because their leaves and stems are being eaten away, you likely have either snails or slugs. Set lids of beer in the garden at night to attract and drown the creatures. Earwigs kill artichokes by feeding on young, emerging plants. Other than seedlings which have already been felled, look for jagged holes in the stems and leaves. Nip the problem in the bud by rolling up and wetting down newspaper, then setting the paper rolls throughout the artichoke patch. The earwigs will be attracted to the paper, which you can then scoop up and destroy.
Wet weather can lead to crown rot, the disease which kills artichoke plants by first turning them slimy, with an unpleasant odor. Another life-threatening disease, curly dwarf virus, can come from diseased nursery stock or other plants. The disease first shows itself as artichoke buds that are misshapen and not as large as normal ones, and which result in a smaller than normal harvest. In addition, plants infected by curly dwarf are smaller than normal, with abnormally furled foliage. Before crown rot, curly dwarf or other diseases kill your artichoke patch, remove the diseased plants to help the remainders survive.