Artichokes are a rewarding garden plant, offering unique edible flower buds. However, like many garden vegetables, they can attract various pests that hinder their growth and yield. Understanding these common adversaries and implementing effective strategies is essential for successful artichoke cultivation. Prompt identification and appropriate action can protect plants from significant harm.
Common Artichoke Pests and Their Impact
Aphids are tiny, soft-bodied insects that infest artichoke plants. These pale, pear-shaped pests gather on leaves and stems, especially on undersides. Aphids damage plants by sucking sap, leading to curled, yellowing, or distorted leaves and stunted growth. They excrete honeydew, a sticky substance that fosters sooty mold, which interferes with photosynthesis. Severe infestations can weaken bud stalks, resulting in undersized or deformed artichoke buds.
The artichoke plume moth (Platyptilia carduidactyla) is a common pest, particularly in perennial artichoke plantings. Adult moths are brownish-buff with distinctive lobed wings. The larvae, the damaging stage, are yellowish to pink and bore into leaves, stems, and developing floral buds. This internal feeding creates tunnels, leaves frass, and damages bracts, causing buds to become underdeveloped, deformed, or unmarketable and leading to yield losses. Stems may also turn black and wilt.
Snails and slugs are common garden pests that damage artichoke foliage. These mollusks feed on leaves, stems, and flowers, creating irregular holes and ragged edges. Their presence is indicated by shiny, silvery slime trails, especially at night or on damp days. In artichokes, they damage developing buds by scraping soft tissues from bracts, causing blackening and reducing harvest quality.
Cutworms are dull brown caterpillars, typically 1 to 2 inches long, that curl into a “C” shape when disturbed. These nocturnal feeders hide in the soil by day and emerge at night to feed. They are known for “cutting” off young plant stems at or just below the soil line, which can be damaging for seedlings and young transplants. Some species also chew holes in leaves or bore into other plant parts. Signs include wilted plants, severed stems, or small tunneling holes in the soil near damaged plants.
Preventing Artichoke Pest Infestations
Proactive measures can reduce pest infestations in artichoke plants. Proper plant spacing is important, as overcrowding increases humidity, attracting pests like aphids and slugs. Ample air circulation keeps foliage drier, making it less appealing to many common pests.
Integrating companion planting offers natural pest deterrence. Marigolds, for instance, can be planted around artichoke patches to repel nematodes, aphids, and beetles. Borage attracts syrphid flies and other beneficial insects, natural predators of aphids. Planting mint nearby may also discourage flea beetles.
Maintaining overall plant health through cultural practices makes artichokes more resilient to pest attacks. Consistent watering supports strong growth, as does balanced fertilization based on soil test results. Avoiding overwatering is important, as excessive moisture can attract certain pests. Good weed control is also beneficial, as weeds provide shelter and alternative food sources for pests.
Crop rotation disrupts pest life cycles by preventing population buildup in the soil. Avoid planting artichokes in the same location year after year; instead, rotate them with different plant families. Physical barriers, such as floating row covers, can prevent flying insects like aphids and moths from reaching young artichoke plants.
Managing Existing Artichoke Pest Problems
When pests are established, various control methods can be employed, starting with less invasive options. Manual removal is effective for larger pests like snails and slugs; hand-pick them from plants, ideally at night or early morning. A strong stream of water can dislodge aphids. If ants are “farming” aphids, managing the ant population helps reduce aphid numbers.
Organic pest control options provide effective solutions without harsh chemicals. Insecticidal soaps break down the waxy outer layer of soft-bodied insects like aphids, leading to dehydration. These soaps are generally safe for beneficial insects and applied directly to pests, ensuring thorough coverage. Neem oil, from the neem tree, acts as a feeding deterrent and insect growth regulator, disrupting the life cycle of various pests. Mix with water and mild dish soap, then spray on affected plants, ideally in cooler parts of the day to prevent leaf burn.
Encouraging beneficial insects creates a natural defense against pests. Lady beetles and green lacewings are natural predators that feed on aphids and other soft-bodied insects. Parasitic wasps target aphid and plume moth populations, laying eggs within pests that develop internally. Providing a diverse habitat with flowering plants attracts these helpful insects, enhancing natural biological control.
For cutworms, entomopathogenic nematodes can be introduced into the soil to target larvae. For severe artichoke plume moth infestations, Bacillus thuringiensis (Bt) can be used. This naturally occurring bacterium targets specific insect larvae without harming other organisms.