As anyone who has done any amount of gardening at home can attest to, an inevitable obstacle that every gardener will face at some point is dealing with garden pests. Kale pests are generally no different from those that affect any of your other plants in the garden. Here I’ve compiled a list of some of the most common bugs that could damage your crops, as well as a few of the less common ones. In addition, there are also a variety of diseases that could affect your kale crops, so I will put up a separate page to discuss those as well. Knowing what pests and diseases can affect your home gardeing crops and how to treat them is very important if you want to be successful at growing kale at home.
One of the most common insects around that can infest so many different kinds of plants is the aphid. Kale is no exception, as aphids are just as likely to feed off it as well. They can do their damage in a couple of different ways. For one, they can suck the sap of the plant. If they’re taking the nutrients out of the kale, the kale isn’t getting those nutrients. As a result, if the aphid infestation is large enough, the plant will soon weaken and eventually die. To make matters worse, while they are sucking the sap, aphids can also transmit plant diseases, which can wreck the plant in an entirely different way. The best thing to do is to keep a watchful eye on your kale crop, inspecting it every few days or so for bugs. If you catch aphids before they are too numerous, you can just spray them off with a jet of water from the garden hose or a spray bottle. Alternatively, you could use insecticidal soap or a hot pepper spray to get rid of them. If you’d prefer to use a more biological approach, you could plant crops nearby that repel aphids, some suggestions being onions or garlic. You could also plant crops that attract ladybugs, or just buy some at your garden store, as ladybugs love to eat aphids. If you release a bag of ladybugs over your crops, and cover them with a large sheet to prevent them from flying away, they will likely eat several of the aphids to help you with your problem.
Another very common kale pest is Pieris rapae, or cabbage worms. These worms can be found infesting several plants in the cabbage family. The larva stage of this insect is a very recognizable caterpillar, with a hairy green body growing up to an inch long. They can have a distinctive yellow stripe running down their back, or else have broken stripes along their sides. They do not move very quickly, but that allows them to feed and do more damage in one place. They will eat both the inner and outer leaves of the plant, causing widespread damage, as well as boring holes within the head. Also, the feces that they drop can contaminate the plant, which provides a very good reason for you to wash your vegetables before using them! After 2-3 weeks of constant feeding, they attach themselves to a leaf and pupate without forming a silk cocoon. This pupal form resembles the larva stage in coloration, being green and yellow as well. Once the pupae has matured, it arises as a cabbage butterfly, usually with white leaves with up to 4 black spots on the leaves. They can commonly be seen over fields. The butterfly form then will lay single white eggs on the underside of the kale leaves, which then hatch and repeat the life cycle. A very effective organic treatment is to introduce the bacteria bacillus thuringiensis, which will specifically target these insects. In addition, there are also several other more toxic methods available, as well as various biological approaches as well.
Another caterpillar that may be found on your crops when growing kale at home belongs to the moth family: the cabbage looper, Trichoplusia ni. This is also a very distinctive caterpillar, quite different in appearance from the cabbage worm. The looper derives its name from the inchworm style of its movement. As it walks, its hind legs come together with its front lets, which causes its whole mid-body to arch up and form a loop shape. If its walking style doesn’t give it away, you can identify it as a green caterpillar with white stripes along its body, about one and a half inches long, with very smooth skin except for a few long bristles along its back. Its effect on the plants is similar to the other kale pests listed above. They chew holes in the leaves and bore holes into the heads, opening up the possibility of introducing diseases to the plant. Young plants are more susceptible to falling ill from these bugs, likely because older plants have more leaves to maintain their nutrition levels. After the feeding phase, these caterpillars spin silken cocoons on the leaves, and after pupation they emerge as brown moths, with distinctive silver designs on their wings. Similarly to the cabbage worms, the loopers are also susceptible to an organic spray of the bacteria bacillus thuringiensis, among other more toxic alternatives.
Flea beetles are another insect that will eat your kale. This garden pest has several different species, with varying colours and markings. They are about 1 mm long, and like many other beetles have a shiny, hard shell. Their names comes from their ability to jump relatively large distances, like fleas, as a result of their large and powerful hind legs. While the immature larvae can feed on the kale roots or leaves, they don’t necessarily do a lot of damage to the plant. Most of the damage is done by the adults. They typically feed on the underside of the leaves, leaving small pits and holes along its surface. As a result, an infestation of flea beetles can stifle the growth of young plants, whereas older plants are more tolerant (probably because they have more and larger leaves to maintain their health). To encourage your kale crop to grow, it is a good idea to check the plants for leaf damage periodically every few days, especially when they are young and small. Once they are more established, they are hardier and require less maintenance. If a flea beetle infestation is discovered, there are a number of organic or toxic methods available to fix the problem.
.Similarly to the caterpillars listed above, the Diamondback moth (Plutella xylostella) larvae damage kale by chewing holes in the leaves, especially on the underside, and boring holes into the heads. The larvae then develop into yellowish pupae, which mature inside a silk cocoon on lower or outer leaves of the plant. From the cocoon will emerge the adult Diamondback moth, which has up to a 15 mm wide wingspan with gray-brown coloured wings with dark spots and lighter stripes or diamond shapes. The adult moth only lays its eggs on kale and other members of the Brassica family.
Growing vegetables at home can be very rewarding, but it isn’t without its challenges. These are some of the most common insects that can be found when trying to grow your own kale at home. However, keep in mind that this list is not exhaustive. Some less common pests that could target your kale crop include root maggots (fly larvae that feed on roots or stems of plants), cutworms (moth larvae that feed on plant stems, potentially cutting the plant down), or several varieties of leafminers (larvae that eat leaf tissue of plants). In any case, it is a good idea to familiarize yourself with the types of pests and diseases that your home garden may face, so that you are better prepared to deal with them if they actually do show up for you.