By: Selima Hauber
The arrival of another La Niña Winter means exceptionally cooler temperatures, making vegetable growing a pleasure! Even with cool temperatures, gardeners still have to stay on top of the insect pests that are after their prized vegetables. One reason Winter is when peak agricultural production happens here in The Bahamas is that the insect pests do not reproduce as fast, resulting in smaller, less aggressive populations, and ultimately, less damage to crops. That does not mean we should let our guard down. Here are the insect pests you might encounter in your garden even during this period of gloriously ‘cold’ temperatures.
White Flies
Whiteflies are small, winged insects that look like white flecks flitting about when you disturb a plant. They are piercing and sucking insects that feed on the contents of the plants’ cells. They not only cause damage directly to the plant by sucking its juices but are also the vectors for microbial pathogens like viruses that could wipe out your crops. Whiteflies are commonly found on tomatoes, cucumbers, eggplant, and peppers.
Aphids are another piercing and sucking pest that is incredibly small but visible to the naked eye. They are pear-shaped and look fat and juicy. There are many types, but most commonly bright green and black aphids are found. Aphids, like whiteflies, secrete the excess sugars that they do not consume from the plants’ juices in small droplets called honeydew. This sugary liquid sticks to the plants’ leaves providing the perfect film for a black fungus called sooty mold to grow on. If your plants have sooty mold, you more than likely have an aphid or whitefly infestation.
Beware of Common Pests
If you have grown tomatoes before, you have surely had the experience of visiting your beautiful plants in the morning only to find sticks where thick, luscious leaves were only hours ago. The culprit is the dreaded tomato hornworm, a voracious caterpillar that can devour a plant overnight. The clever larva is a master at biomimicry, looking quite like the tomato stems itself, in an effort to evade predators. If leaves have disappeared overnight, and there are small, spherical, greenish-brown pellets dotting the ground below, do not leave until you have found the worm and removed it. The hunt takes a minute, but it is worth the time to save your plants. There are other caterpillar species that attack a variety of crops, leaving holes or damaged leaf margins. Droppings and adult moths or butterflies indicate the presence of plant-eating larvae.
The cucumber striped beetle is a pest that is new to me here in Eleuthera. This pest decimates the leaves of plants in the cucumber family including melons and pumpkins. The small beetle can be found in the flowers and on the leaves often mating. These beetles must be killed at first sight, or in short order, your plants’ leaves will become a lacy skeleton, and all hope will be lost.
Now before you rush off to the garden supply centre and buy something to wage war on the pests, you should know that there are also beneficial insects in your garden that help keep the pest populations under control, and they should therefore be protected at all costs. The most easily identifiable beneficial insect is the ladybug beetle. Ladybugs are a gardener’s best friend as they devour aphids.
Do not purchase the first treatment you come across, or you could be destroying the ladybugs along with other beneficial insects too. Not all pest control is created equal. There are strong, broad-spectrum treatments that eradicate the good and the bad. The most popular one amongst Farmers and backyard growers in The Bahamas is Sevin dust. This dust is a pretty strong chemical that should not be used flippantly as it not only kills the beneficial and pest insects, but pests can quickly develop resistance to it. Restricted, responsible use of this dust is for the control of the cucumber striped beetle as there are practically no treatments that effectively control this pest. Instead of making it snow over the entire plant, apply a very light dusting only to the part of the plant where the beetle was seen. One very light application is generally enough to last most of the season if caught early enough before the population explodes.
The Beauty of Being a Producer
The beauty of being a producer today is the wide range of ‘soft’ or biological treatments. They are referred to as biological as they are either extracts from plants or actual bacteria or fungi that attack and kill insect pests. The most commonly available biological treatment for caterpillars is Bt, which is a bacterium called Bacillus thuringiensis. Bt is locally marketed under the trade names Thuricide or Dipel. This bacterium exists naturally everywhere and is not harmful to us. Bt is always in an organic Farmer’s arsenal. A plant extract that controls insect pests is neem oil which works as a feeding deterrent and a growth regulator. Look for commercial products labelled ‘neem oil’ or its active ingredient azadirachtin.
Other safe treatments for insect pests are horticultural oils and insecticidal soap. Horticultural oils work best in controlling soft-bodied pests like aphids and whiteflies. Oils should be applied in the very early morning or late afternoon. Avoid applying in the middle of the day when the sun is directly overhead or when daytime temperatures are above 90 degrees Fahrenheit. Insecticidal soaps are also effective at controlling soft-bodied insects by damaging the protective coating, causing them to dry out.
At-Home Pest Treatments
If you really want to play it safe and save some money, you can make your own pest treatments with ingredients already in your kitchen. The website www.oisat.org – Online Information Service for Non-Chemical Pest Management in the Tropics has an extensive database of easy-to-prepare pest treatments. Simply enter the insect pest in the search window, then scroll down to select a recipe for a spray. Because these are not concentrates, you must use them early and often for them to be effective. Consider these as preventatives and apply them even before a couple of pests turn into a burgeoning, destructive population.
With these tools, you can protect the beneficial insects that are helping you and increase the chances of achieving a successful growing season. Be kind to your plants and protect your health by choosing the gentler ways of controlling garden pests.
