Black Bean Aphid
Black Bean Aphid
Deal with aphids organically: Method 4
Deal with aphids organically: Method 3
Deal with aphids organically: Method 2
The Black Bean Aphid is a sap-sucking insect that forms dense colonies on the soft young growth of shrubs and vegetable plants. They have complex life cycles involving different host plants. Aphids spend the winter colonising Euonymus europaeus, Viburnum and Philadelphus plants. In the summer, Black Bean Aphids migrate to Broad Beans, Nasturtium and Dahlias. They suck the sap from these plants, causing yellowing and wilting as sap stores are depleted from the plant cells.
Aphids are food for many predatory insects, like ladybirds!
Can multiply quickly, especially when ants are present.
Adults: Mature aphids are soft-bodied insect up to 2mm long with a black body. Some have white flecks on their upper body. They can be winged or wingless. Nymphs: The nymphs are smaller and paler in colour, with no wings. Eggs: Laid on the host plants, too small to be seen with the naked eye.
Dense groupings on areas of new growth. Honeydew. Honeydew can encourage the growth of black mould. Honeydew can attract ant infestations. Wilting. Leaf Yellowing. Leaf distortion. Damage is rarely permanent.
The introduction of ladybirds, hoverfly larvae, lacewing larvae and several parasitic wasps in a garden situation will reduce numbers. You can attract the latter to your garden by installing insect habitats, such as wildflower stips and log piles. Companion planting with strong-smelling herbs such as Basil, Chive, Allium and mint are believed to deter aphid activity. Nasturtium is a brilliant buffer plant which can attract insects away from vegetables and fruits. Aphids aggregate in areas of new growth, so be sure to check in all the nooks of plants, especially under leaves! For heavier infestations, treat plants with a strong jet of water to dislodge the insects from the plant. Alternatively, use a light, soapy mixture sprayed on the plant or even just squashing them. Indoor plants can be rinsed under a tap or shower. A mixture of tomato leaf and distilled water is believed to repel aphids. Once the leaves are drained, dilute the remaining mix with 1-2 cups of water. Tomato plants contain the same allergens as nightshade. It's not advised to use this method if allergic to nightshade. Garlic or chilli-based sprays diluted with water can act as a natural insect repellent. Placing ant traps near infested plants will help to control secondary ant infestations. Managed areas of herbaceous plants provide the perfect cover for predatory insects. Sowing broad beans in autumn and overwintering seedlings/plants will ensure that the beans miss the migration of the black bean aphid from the over-winter host plant. Pinching out the tops of broad beans when they have reached the desired height will help prevent an attack.
As the black bean aphid predominately affect food crops when selecting a pesticide it is advisable to ensure the edible food crop is listed on the label and fully follow the manufactures instructions regarding the maximum number applications, spray interval and harvest interval periods required. Always seek professional advice for suitable chemical controls. Spraying flowering plants should be avoided to protect beneficial pollinators.