Insects That Eat Daffodils

Bulb-Eating Insects

• Daffodil bulbs attract narcissus (Merodon equestris) and lesser (Emereus spp.) bulb flies. Both are most active in spring. Narcissus bulb flies' 1/2-inch or larger, black, hairy bodies and orange or yellow markings, resemble bees. Smaller lesser bulb flies have blue-black bodies with a metallic sheen. Female bulb flies lay eggs in the ground around daffodil plants. The newly hatched larvae burrow into the bulbs and feed before overwintering and emerging as adults to repeat the cycle. Symptoms of M. equestris-infested bulbs show up during the spring following original infestation. The damaged, nonflowering bulbs produce a few small leaves instead of vigorous, healthy shoots. Lesser bulb fly larvae attack daffodil bulb in groups of up to 40. They quickly liquefy the inner pulp. These insects prefer infesting partially decayed bulbs rather than healthy ones.

Leaf-Eating Insects

• Three aphid species, foxglove (Aphididae solana), green peach (Myzus persicae) and potato (Macrosiphum euphorbiae), attack daffodil foliage. These tiny, pear-shaped insects pierce the leaves with their mouths and suck out the fluids. They typically appear in clusters on leaf undersides. Adult aphids may be wingless or winged. Wingless foxglove aphids are solid green or yellow; winged ones have dark-brown heads. Black patches on their abdomens distinguish winged green peach aphids from their yellow, pink or green wingless relatives. All adult potato aphids are solid yellow, green or pink. Serious aphid infestations cause curled or distorted leaves and stunted growth. Thrips (Thysanoptera spp.) measure less than 1/20 inch long. Adults have fringed wings. At different life stages, they may be white, yellowish, brown or black. These pests favor concealed feeding spots in tightly folded leaves and flower buds.

Controlling Bulb Flies

• The best way to keep bulb flies from finding your daffodils is examining each bulb carefully before planting it. Buying firm, clean bulbs and taking care not to injure them before and during planting discourages lesser bulb flies. Lifting and disposing of plants and their bulbs at the first sign of damage limits the spread of both fly types.

Controlling Aphids

• Temperatures between 65 and 80 degrees Fahrenheit stimulate aphid activity. Checking the daffodil foliage, especially its undersides, frequently in mild weather is the quickest way of spotting aphids. A strong spray of water from a garden hose removes small aphid infestations. Larger populations may require chemical control with a water and neem oil, insecticidal soap or parafinic oil. These treatments have no lasting effect. Reapplication is required if aphids reinfest the daffodils.

Controlling Thrips

• Thrips often spread to ornamental plants from nearby weeds. Removing and destroying weeds in your garden eliminates that possibility. Regular watering keeps the daffodils strong enough to recover from existing damage. Spraying small daffodil plantings with water dislodges the pests. Insecticides seldom harm thrips. Repeat applications of horticultural oils at five-to 10-day intervals is useful against larvae and recently emerged adults.