Green beans are one of the easiest vegetables to cultivate in the yard, yielding a large crop with little effort. However, waking to stand thinking, what is eating my green bean plants can be frustrating.
Most bean pests are easily handled with natural methods, and pesticides are rarely used. In your bean patch, keep an eye out for pests.
Come to the springtime; it will be time to plant green beans for a summer harvest. However, you won’t be the only one who wants to eat holes in your garden vegetables. You can find pests such as rabbits or smaller insects such as aphids, thrips, slugs, and beetles who’ll enjoy the feast.
While some gardeners use pesticides to stop insects, there are natural alternatives to stop insects. In our guide, you can learn what leaves holes in green bean leaves.
By the end, you’ll know enough to know how to deal with green bean insect pests, no matter what they are. (Learn What Is Eating My Hosta Leaves)
Insects On Green Beans
Here you can find the common green bean pests feeding in your garden.
Aphids are tiny insects that are green, red, or gray. They are most common in the early summer, but they can occur.
They don’t eat to leave holes in the leaves; instead, they penetrate the leaves and stems, sucking the plant’s juices. During aphid infestations, plants may droop, and foliage may become yellow.
Honeydew, a sticky material generated by aphids, may also be found on the leaves and soil. Because ants feed on honeydew, an increase in ant numbers can suggest aphid infestations. The aphids themselves can be found on the undersides of the leaves.
Aphids appear in cycles, so they’ll most likely go away on their own in a few weeks. Ladybugs, predatory wasps, and lacewings eat aphids and may keep populations in check without your help.
If aphids are harming your bean plants, spray them with a constant stream of water from your garden hose, or you can apply insecticidal soap to the leaves. Coat the tops and bottoms thoroughly with soapy water to blanket the aphids. (Read Aphids On Pepper Plants – What to Do)
Thrips are microscopic, scarcely detectable insects that suck the juices from bean plants, similar to aphids. If they occur while beans are flowering, they may prevent pollination or cause malformed pods. To keep thrips at bay, cover the soil with aluminum foil after planting or use insecticidal soap.
Mexican bean beetles resemble giant brown ladybugs, and while they can appear early in the summer, they do the most harm in the middle to late summer.
You might also find shiny, green Japanese beetles or brown-spotted bean leaf beetles chewing on your plants. The veins of the leaves are usually left intact as these hungry insects feed on the undersides of the leaves. Beetles will occasionally eat on pods and stems.
Plant fast-growing cultivars that mature before beetles appear to outsmart them. To kill beetles, handpick them from bean plants and dump them in a pail of soapy water. Keep an eye out for their yellow, fuzzy larvae and yellow eggs, which should be destroyed as well.
Bean leaf beetles in Minnesota have yellowish-green wings with four black spots and black markings on the outside borders.
Corn earworms and cabbage loopers aren’t fussy eaters. Both pests eat beans, corn, and cabbage. These bugs can quickly kill an entire row of beans when planted late.
To stop how much caterpillars feed, spray the beans with Bacillus thuringiensis (Bt) every few days. These insects’ guts are paralyzed by Bt, causing them to starve. Three- or four-days pass, but the insects quit feeding. Also, Bt is safe for other animals and insects.
How Do I Keep Bugs Off My Beans?
Pest problems vary from year to year, but appropriate cultural practices can help to limit them and guarantee strong bean plants that can withstand bug attacks.
Delay Spring Planting Time
By delaying the planting of snap beans in the late spring, you can reduce the danger of bean leaf damage. Growing snap beans takes roughly 60 days. (Learn How To Stop A Dog From Digging Under A Fence)
- It’s critical to monitor your garden if you’ve had bean leaf beetle infestations in the past.
- The optimum time to check is between 12 and 4 P.M.
- Early in the season, when beetle eating can inflict the most harm, inspect your plants.
- Examine for insects and evidence of eating damage.
- Protect your snap beans if you notice moderate or severe injury of 6-10 holes per leaf on 10% of your plants, especially once the first set of true leaves appears.
- Snap beans become more resistant to defoliation as they get larger and have more leaves.
Remove Beetles From Plants
- To limit the amount that bean leaf bugs feed in your garden, remove them.
- When plants are disturbed, bean leaf beetles frequently fall to the ground.
- Place the bucket beneath the plant so that it can catch the seeds when they fall.
- In larger gardens, this strategy may not be workable.
To protect your snap beans against bean leaf beetles, spray them with a pesticide if necessary. Please make sure there are enough of them to warrant treatment. Later in the summer, treating bean leaf bugs with spray is less critical.
Bean Leaf Beetles
The bean leaf beetle (Cerotoma trifurcata), often known as string beans or green beans, is a pest of snap beans.
- Adult beetles eat the undersides of leaves, leaving spherical holes with a diameter of 1/8 inch, and can feast on pods directly.
- Adults are most active from mid-May to early June and again from mid-July to September.
- A black triangle appears at the top of the wing covers of all bean leaf beetles, and some have four black spots, while others have none.
- Adult bean leaf beetles spend the winter under foliage, in clumps of grass, or inside dried curled dead foliage in leaf litter.
- Around the base of the beans, females lay clusters of about 12 orange eggs in the dirt.
- They attack soybeans, clover, dry edible beans, and various leguminous weeds besides snap beans.
- Depending on the temperature, eggs hatch into larvae one to three weeks later.
Keep Pests Off Beans
- Water your green beans twice a week, using an inch of rain or additional irrigation. Be careful not to over-water your beans, as they are more susceptible to mites.
- Get rid of any weeds growing around the garden’s edges or adjacent. These weeds can harbor spider mites that attack green bean plants.
- Occasionally saturate the bean leaves with water. This deters mites and reduces the dusty conditions mites enjoy. To reduce dust in the garden, periodically water bare dirt paths and other exposed soil areas.
- Pinch or cut off highly affected leaves or larger sections of the green bean, especially if the webbing is prevalent. Bag and dispose of the plant you have removed.
- Infested green bean plants need spraying with insecticidal soap or horticultural oils like neem, and you can reapply every 10-14 days.
Weed your prospective bean patch and the surrounding space two weeks before planting green bean seeds or seedlings. Cutworm larvae, slugs, and snails hide in weeds and eventually find their way to your young plants, severing them at the root.
Encourage beneficial insects to eat green bean bugs in your garden.
To deal with cutworm, you can place collars around your seedlings for protection against burrowing pests. Use a bottomless paper cup or doubled-over aluminum foil to wrap around each seedling. Keep these at around 4 inches in height, so the collars sit 2-inches below the soil and 2 inches above ground level.
A thick layer of mulch is applied once your seedlings are 2 inches tall as the mulch prevents bugs like striped cucumber beetle laying eggs in the soil.
Setting row covers over your young bush bean plants can stop rabbits or larger insects like striped cucumber beetle and slugs from damaging your plants. Remove row covers as your plants’ flower, so pollinating insects get to the blossoms.
Tips For Healthy Green Beans
Plant green beans late in the spring.
Learn to recognize hazardous insect, pests, and plant diseases and their damage. This understanding will help with both home control and getting help from a garden center.
If flying insects are a severe issue in your garden, consider short, free-standing bush beans that may be covered with a row cover system.
Remove the entire crop after harvesting the last green bean. Otherwise, pest pests could lay eggs and attack the following year’s crop growing in the same spot.
While it’s easy to hose off tiny insects, please don’t do it as your bean plants bloom. A strong hose spray may damage the plants’ flowers, thus reducing bean output. In addition, using a garden hose should also be done early in the morning to allow leaves to dry.