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Pest, Disease & Weed Timing CalendarsTrap Crop Planting Calendar
A trap crop only works if it is more attractive than the main crop at the moment the pest shows up, which makes planting date the key decision.
Key points
- Plant trap crops early so they are more attractive than the main crop on pest arrival.
- Use extension pest timing information to count backward from first arrival.
- Scout and manage the trap, and remove it before it becomes a source of pests.
- Start small and keep notes on whether it works.
What is a trap crop?
A trap crop is a plant grown to lure a pest away from the main crop, usually because the pest prefers it for feeding or egg laying. Growers then manage the pests where they gather, for example by removing the trap or treating a small area instead of the whole field.
Trap crops are not magic. Research and extension reports show mixed results that depend on the pest, the crop, the layout and the surrounding environment. They work best as one piece of an IPM plan.
Check whether your crop and pest have been tested. Some combinations have solid regional evidence, while others have little.
When should a trap crop be planted?
Plant it early enough to be at an attractive stage when the pest arrives. Start by learning when your key pest first shows up in your area, using extension pest reports, degree-day information and your own scouting records. Then count backward from that date using the growing time of the trap crop.
For example, if your records show a pest arriving around the time your main crop is a few weeks old, the trap may need to be seeded a few weeks before the main crop. Use local data, not an example date.
Keep a planting log for both trap and main crop with dates and weather so you can see how timing lined up with pest arrival.
Where does the trap crop go?
Common patterns include a border around the field, a strip along the side where pests enter, or scattered blocks inside. The best arrangement depends on how the pest moves, and extension publications for specific crops describe layouts that have been tested.
Keep traps close enough to intercept pests but far enough that you can work them without harming the main crop. Make sure irrigation and access are planned.
Think about wind direction and neighboring crops. A trap that sits upwind of the main field can send pests the wrong way if it is poorly managed.
- Identify the direction pests come from
- Match trap crop species to the pest
- Stagger plantings to extend attractiveness
- Leave room for equipment and workers
How do you manage the trap once it is working?
A trap that concentrates pests also concentrates risk. Scout it often. When numbers build, decide how you will deal with them, whether by targeted treatment where the label allows, by removal or by destroying the crop before pests move on.
Do not let a trap crop become a pest nursery. Time its removal so pests do not spread to the main crop as the trap crop ages. Follow all label and pre-harvest rules for any product used in a trap area.
Any treatment on a trap crop must still follow the label for that crop, including intervals and pollinator rules.
What are the common mistakes?
Planting too late, planting too little, using a species that is not preferred by the local pest population and ignoring maintenance are the usual ones. Some growers forget that a trap crop needs water and fertility to stay attractive.
Keep notes on trap performance, such as pest counts in the trap and in the main crop, so you can see whether it helps.
Consider labor, since one more crop to plant, scout and remove adds work. Include that in your decision.
When should you skip it?
On small plots or where pests move in from all directions, a trap may not pay. If labor is tight, an easier measure such as row covers or timed planting may be a better choice. Ask extension for results from trials near you before investing in a large layout.
Always treat it as an experiment at first. Try a small area, note what happens and expand only if results justify.
Ask neighbors if they use trap crops too. Area-wide approaches sometimes work better than isolated ones.
What does a sample timeline look like?
For example, a grower might seed the trap crop first, plant the main crop a few weeks later, scout both every week and remove or manage the trap when pest numbers peak. The exact spacing in time depends on pest arrival in your area and the growth rate of each crop.
Write your own timeline and compare it with what you see. Adjust the gap between plantings in the next season.
Sources and further reading
Last reviewed: November 2026. Educational information, ranges only. Confirm timing with your county extension office.