Slugs and snails chew leaf holes in many plant types, including hibiscus, hosta, basil, cabbage, tomatoes, lettuce, cucumbers and pepper plants.
Try mixing dish soap with water in a spray bottle (a few squirts of dish soap, the rest filled with water, and shake a bit to mix). Spray the plants from top to bottom to get rid of and discourage bugs. Respray after heavy rain.
If you decide to use insecticides, Bacillus thuringiensis (Bt), neem oil (azadarachtin) or spinosad, which are derived from natural ingredients, can be effective against beetles or caterpillars. For soft-bodied insects such as aphids or whiteflies, try insecticidal soap, Neem oil, or other horticultural oils.
Though technically a larva, the cabbage looper is a prevalent pest affecting lettuce, cabbage, broccoli, spinach, and related crops, known for its worm-like appearance. You'll see images of the pest in the thumbnail and video.
Insecticidal soap
Insecticidal soap is one of the best ways of getting rid of aphids, as well as lace bugs, leafhoppers, mealybugs and thrips. To create insecticidal soap, combine one cup of vegetable oil with one tablespoon of dishwashing soap or pure castile liquid soap at Walmart.
Dishwashing Liquid or Castille Soap
Deterring them from wanting to eat the plant. Care must be taken with the soap-to-water ratio, because too much soap can damage the leaves and make the plant very unhappy. But occasional use for pest treatment will be just fine.
While potentially distasteful to some, produce that has been nibbled on by insects is generally safe for consumption. Other bite marks or evidence of animals aren't as safe. Produce that looks like it's been snacked on by rodents or rabbits should probably be passed up.
Vegetable Oil Spray
A homemade, natural pesticide made from vegetable oil mixed with a mild soap (such as Dr. Bronner's Castile soap) can have a devastating effect on certain troublesome insects, such as aphids, mites, thrips, etc.
While true that holes in leaves can be indicative of a nutrient deficiency such as potassium, more often than not this leaf damage is actually caused by hungry herbivores.
The most effective insecticides against leaffooted bug are broad-spectrum, pyrethroid-based insecticides, such as permethrin. However, these products are quite toxic to bees and beneficial insects. Insecticidal soap or botanicals, such as neem oil or pyrethrin, may provide some control of young nymphs only.
Caterpillars that attack the fall crop are usually the most troublesome field pests of lettuce. In the greenhouse, aphid and cabbage looper infestations often cause problems. Cutworms, whiteflies, leafminers, and slugs are slightly less important greenhouse pests.
How to Get Rid of Aphids, Whiteflies, Thrips & Mites on Lettuce. As soon as Aphids, Whiteflies, Thrips or Mites are noticed, spray plants thoroughly every 5-7 days with Yates Nature's Way Vegie & Herb Spray. It's important to spray both sides of the foliage, as pests commonly hide on the undersides of leaves.
Treat Your Leafy Greens Carefully. If you are pretty sure the holes in your leafy vegetables were caused by insects or slugs, they should be safe to eat, as long as you wash them thoroughly, and remove any damaged portions.
The open structure of these vegetables allows insects to penetrate the entire head. Often, insects may be found between the innermost layers of leaves of an infested head. Therefore, each leaf must be washed and checked individually. The use of a light box for checking lettuce can be extremely convenient and helpful.
Slugs and snails chew leaf holes in many plant types, including hibiscus, hosta, basil, cabbage, tomatoes, lettuce, cucumbers and pepper plants. Leaf holes from slugs and snails offer these clues: Holes are large and irregular in shape. Hole edges are relatively smooth.
Use repellents. Non-toxic repellents are available in garden centers that naturally repel bugs with such ingredients as garlic or hot-pepper oil. Some are spray-on liquids, others are granular that can be scattered around the base of plants.
Adult flea beetles cause the most damage by feeding on the leaves and stems. They create shallow pits and small rounded, irregular holes (usually less than 1/8 inch) in the leaves. This type of damage is unique to flea beetles.
Herbicide. One of the most common uses for household vinegar is as an all-natural weed killer. You have to be careful when spraying it around certain plants as it may be harmful to some, but when used on those pesky hard-to-kill weeds, they will disappear in two to three days' time.
There are almost countless uses for cinnamon in the garden: it can be used as a nature-friendly pesticide, a repellent against annoying insects, or as a catalyst to promote root growth in plant cuttings.