Pests in Gardens

Even a hose can fight some garden pests. Jupiterimages/Comstock/Getty Images

Keeping a garden healthy requires a lot of work. Soil must be tilled and irrigated, and waterings must be carefully to measured to avoid over- and under-hydrating plants. Gardeners must choose between natural and chemical fertilizers and must keep their plants safe from frost or too much sun. Of course, a homegrown vegetable or flower makes the effort worthwhile, but gardeners must also watch out for loathsome pests that can destroy their crops.

Nematode

Nematodes feed on the roots of plants, preventing them from absorbing nutrients. baby plant with root system image by joanna wnuk from Fotolia.com

Nematodes are a common garden pest and often decimate vegetable harvests. Described by the University of California Davis as "tiny eel-like roundworms," nematodes feast on the roots of vegetables, preventing them from properly absorbing water and nutrients in the soil, slowly killing the plant. More than 20,000 species of nematode exist, and they range in size from microscopic to several meters, though the ones living in gardens typically can't be seen and are identified by the swollen patches, known as galls, they leave on roots. No chemical pesticides are available to fight nematodes, requiring gardeners to rely on natural methods. UC Davis recommends making a patch of soil fallow to rid it of the worms, keeping it free of all plant life, including weeds, for a year or two. Water the soil heavily to induce hatching of nematode eggs, and wait as the worms die off from starvation due to the lack of plants in the soil.

Slugs and Snails

Slugs can be killed with a generous sprinkle of salt. slug descending 2 image by Scott Philbrook from Fotolia.com

Slimy hermaphrodites, slugs and snails glide around on a makeshift foot, leaving a trail of goo as they eat their way through gardens. Members of the mollusk phylum, all snails and slugs are capable of laying eggs, which they do several times a year, increasing their numbers exponentially. The creatures thrive in damp climates, avoid sunshine and chew holes in leaves, devour flowers and nibble on young fruits, like tomatoes and strawberries. To reduce slug and snail populations, eliminate their hiding places, like weedy clumps, leafy branches growing close to the ground, patches of ivy and pieces of debris, all places they love to hide.Slug and snail eggs can be killed with salt, and the Garden Helper website recommends checking for slugs and snails in the early morning as they will not yet have resumed hiding after their nighttime activity. Also, crushed eggshells scattered around plants will naturally fertilize the ground, and their sharp edges will cut slugs and snails, mortally wounding them.

Aphids

Ladybugs are an enemy of aphids, so don't remove them from a garden. ladybug image by Marek Kosmal from Fotolia.com

Armed with sharp, pincer-like teeth, aphids love to suck the sap and juice from plants, effectively destroying gardens. The small bugs have a pear-shaped midsection and can be brown, red, green, black or yellow and vary in size. Aphids also secret a sugary substance, honeydew, which attracts ants, furthering the infestation problem. To ensure a supply of honeydew, ants will also protect aphids from insects that would otherwise kill them, so fighting ants is also fighting aphids. The insects prefer feasting on the young leafs and shoots of various plants and vegetables, like pumpkin, cucumbers and tomatoes as well as pine, oak and maple trees. By drinking the sap of plants, aphids stunt their growth and ruin crops. To remove aphids, the Vegetable Gardener website recommends vigorously spraying plants to blast them away while also removing honeydew, thus ridding them of their ant-protectors. Washing plants in a mixture of soap and water will also poison the bug without the use of harsh chemicals.

References

• University of Nebraska: What are Nematodes?
• UC Davis: Garden Nematode Control
• The Garden Helper: Slugs & Snails
• UC Davis: Slug & Snail Management Guidelines
• Vegetable Gardener: Controlling Aphids
• University of Missouri: Aphids

Resources

• Colorado State University: Garden Insects & Pests