How to recognize them and keep from destroying your garden
In New Jersey, common garden pests include populations of aphids, caterpillars and sometimes cute but always destructive furry little critters like mice, voles and rats. In small populations they generally do not pose a serious problem or create risk of spreading germs/viruses, but when larger numbers are present, your garden may show signs of damage. You may notice the distortion of leaves or buds, clear marks of leaves being eaten, leaves or blossoms turning brown and dying, and possibly the ground being churned up or riddled with mounds and tracks. Here we review these pests and how to deal with them.
Some of the most destructive insect pests to your garden are the Aphids. Aphids are also known as plant lice and the common types and names include greenflies, blackflies, or whiteflies. They are very small, soft-bodied insects that actually may be pale green, pink, black, white or yellow, depending on the species. Some stages of the life cycle are winged, while others will be wingless. You will know you have them thriving in your garden if you see your garden plant leaves are yellowing and distorted. Also, you will find them in clusters on the tips of new growth and leaf undersides. These clusters are easily visible, easy to check for, and when you see them, you know you need to take action to save your plants.
The aphids feed by sucking the plant juices, which causes leaves to become curled and yellow. After feeding, they secrete a sugary fluid called “honeydew” that attracts ants and may cause the growth of a sooty black fungus on leaves. In small numbers aphids do little damage, but they reproduce rapidly and will spread diseases among plants, which will cause further destruction of the beauty of your garden. The black gunk eventually coats all leaves and looks very unappealing.
The first step to rid your garden of aphids is to hit your plants with a strong spray of water to reduce the population. When spraying, be sure to treat the top and underside of the leaves. If the aphids return, you will need to spray with an insecticidal soap or horticultural oil. You could also choose to introduce a natural insect parasite(s) and predator(s) to your garden environment, which may help to reduce aphid populations. In addition, you can buy liquid or pellets that you soak into the ground at the base of plants, shrubs and trees, that makes them unattractive to the aphids.
These are frequently found in New Jersey vegetable gardens and their presence is obvious, as you will see the leaves of your vegetable plants have holes and are clearly eaten through. Hornworms are easily recognized as large, green, fat caterpillars of up to 5 inches in length. You’ll find them feeding voraciously on the leaves and fruits of your tomatoes, peppers, eggplants, and potatoes. As adults, they are spectacular looking sphinx moths with grayish-brown wings featuring orange spots on the body. Their wings span an average of 4 to 5 inches. The average life cycle is one generation per year. They winter in the soil in 2-inch brown spindle-shaped pupal cases and then emerge as adult moths in late spring to early summer. As adult moths, they lay greenish-yellow eggs on the undersides of your vegetable plant leaves. The destruction they cause comes as the eggs hatch and the hungry new caterpillars feed for about a month on the sustenance of your vegetable plants. Then they enter the soil to pupate, and the cycle repeats.
To humans, these caterpillars pose no danger, and can be removed from your plants manually but, it is important to note – If you find a caterpillar with what looks like grains of white rice attached to its body, do not remove it. What appears to look like rice grains are the pupae of a parasitic wasp that attacks hornworms and will help control the population of the troublesome hornworms in your garden, naturally.
Typically found in the Eastern U.S., is the Japanese beetle. Iridescent Japanese beetles are often considered pretty but are also known to be very destructive. As adults, you will find they grow to be about 1/2″ long and they have an appetite for a wide variety of plants, which is what makes them so troublesome. They will feed on nearly every kind of ornamental and edible plant, and on occasion they do this in troublesome large numbers. You will know they are there as they chew leaf tissue from between the veins, leaving a lacy skeleton of what the leaf once was. Prior to pupating, the 1-inch-long, white, c-shaped grubs live in the soil and feed on the roots of many plants. Grubs are often a problem in lawns. No vegetable or herb plant or ornamental planet is safe from these pests.
Fortunately, the Japanese beetle is easy to spot and is also fairly easy to knock into a can of soapy water. You could also use a “yellow target trap” baited with a pheromone attractant, which often works very well but sometimes too well. If you place one near your garden, you may end up drawing beetles in from all over town. It might be better to deter feeding adult beetles by using a spray of neem oil on your plants. They do make various traps for Japanese beetles, and you can discuss these with your gardening or landscaping professional. For grub control, you can use parasitic nematodes on your lawn and in your garden beds.
Remember to ask us, your New Jersey landscaping experts, about the best ways to fight any given garden pest you may have on your property.