Sooner or later something will eat your vegetables. It might be a caterpillar on the kale, aphids on the tomatoes or a rabbit that finds your lettuce. Most of these problems are manageable, and you rarely need strong chemicals to handle them.
This guide uses integrated pest management (IPM), the approach recommended by university extension services: prevent problems, monitor early, identify what you are dealing with and use the least toxic option that works. It covers common insect pests and animals and how to protect your crops. Part of the Grow Your Own Food series.
Walk your garden every few days, identify before you treat, and start with hand-picking, row covers and fences. Use sprays only when needed, and always follow the label.
The IPM approach in four steps
| Step | What to do |
|---|---|
| 1. Prevent | Grow healthy plants in good soil, with enough sun and water. Space plants for airflow, rotate crops and remove diseased debris. |
| 2. Monitor | Check leaf undersides and stems regularly. Catch problems early. |
| 3. Identify | Find out what is causing the damage. Take a photo or sample to your local extension office if unsure. |
| 4. Act with the least toxic option | Start with hand-picking, water sprays or barriers, and escalate only if numbers keep rising. |
Common insect pests and what to do
| Pest | Signs | Start with |
|---|---|---|
| Aphids | Clusters of tiny insects, curled leaves, sticky residue | A strong spray of water, and encouraging beneficial insects |
| Tomato hornworm | Large green caterpillars, stripped leaves, dark droppings | Hand-pick and drop into soapy water |
| Cabbage worms and loopers | Holes in kale, cabbage, broccoli | Row cover from planting, and hand-picking |
| Flea beetles | Tiny "shot holes" in leaves of greens and eggplant | Row cover, and keep plants well watered |
| Squash bugs | Wilting squash, clusters of bronze eggs on leaf undersides | Hand-pick and crush eggs, and check plants regularly |
| Slugs and snails | Ragged holes, slime trails, damage at night | Hand-pick at dusk, reduce hiding places and water in the morning |
Row cover is a lightweight fabric that lets in air, light and water. It can deter leaf miners, cabbage maggots, cabbage loopers, onion maggots and flea beetles, and can also keep rabbits, deer, birds and groundhogs off crops. Remove it for crops that need pollinators, such as squash and cucumbers, when flowers appear.
Animals: rabbits, deer, groundhogs and birds
| Animal | Damage | Protection |
|---|---|---|
| Rabbits | Clipped seedlings and greens | Low fencing with small mesh, with the bottom buried or bent outward |
| Groundhogs | Beans, squash, greens | Sturdy fencing with the bottom buried, or a fence with an outward flare |
| Deer | Browsing on almost everything | Tall, sturdy fencing is the most reliable option |
| Birds | Seeds, seedlings and berries | Netting or row cover |
| Burrowing animals (voles, gophers) | Roots and bulbs | Hardware cloth under raised beds. See How to Build a Raised Garden Bed. |
Scent repellents and decoys give mixed results. Physical barriers are the most reliable.
Prevention habits
- Rotate crops. Do not plant the same crop family in the same spot year after year.
- Clean up. Remove diseased plant material and do not compost it.
- Water at the base to keep leaves dry. See Watering and Mulching.
- Plant flowers that attract pollinators and beneficial insects near the garden.
- Use resistant varieties when available.
If you decide to use a spray
- Identify the pest first.
- Choose a product labeled for your crop and pest.
- Read and follow the label, including the interval before harvest.
- Spray in the evening to reduce harm to bees, and avoid spraying open flowers.
- Wear protective gear as directed, and keep children and pets out of the area.
- Wash produce before eating.
Even "natural" or organic products are pesticides and can harm beneficial insects. See Organic Vegetable Gardening.
When to get help
If you cannot identify a pest, or a problem keeps returning, contact your county extension office or Master Gardener helpline. They can identify pests and diseases and suggest options for your region.
FAQ
What is integrated pest management?
How do I keep rabbits out of my garden?
Is it safe to eat vegetables that have been sprayed?
Sources and further reading
