One potato, two potatoes, three potatoes, four. Yes, this is child’s play, but it can also be the anthem of potato diseases and pests that are ready, willing and able to devour your crop.
Do pests eat potatoes? Yes, pests like Colorado potato beetles, slugs and wireworms eat the tubers, while many other pests attack the foliage of potato plants. Then there are the potato diseases and ailments that can decimate your crop.
And they told you potato cultivation was it easy? Actually, it might be. All of these threats to your potato patch can be addressed with a little preventative action on your part. I’ll walk you through the most common potato diseases and pests that affect plants and teach you how to avoid problems so you can still have a big, healthy crop.
Common potato pests
You love baked potatoes. Your family loves homemade french fries. But we can add a long list of potato-loving pests to that list. Let’s look at the most common potato pests, how to recognize them and what to do if they appear in your garden.
1. Colorado Potato Beetles
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With a name like “potato bug,” you might think this pest is laser-focused on potato plants, but you’d be wrong. Adult Colorado potato beetles they overwinter in the ground and then in the spring, emerge and search for a host plant.
Potatoes are their favorite, but any plant in the potato family will do, including tomatoes, peppers, eggplants, tobacco, and some types of weeds. The adult is a small beetle with an oval, yellow body and black stripes on its wing coverts. Larvae are bright pink with black heads.
Both adults and larvae feed on potato leaves, but the worst damage is caused by the third and fourth instar larvae. These large larvae can remove all the leaves from a potato plant within 48 hours. This is a fatal condition for flowering potatoes, as even a 6% defoliation can kill the plant.
Use one insecticidal spray, such as Bonide’s specifically designed to defeat Colorado potato beetles, to combat these common potato pests.
2. Potato Leafhoppers
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Potato leaflets it’s not an issue as long as they’re young. Adults are yellow-green and very tiny, while nymphs are even smaller and wingless. Leafhoppers become a problem when reproduction begins and then it is continuous. These pests produce three to four generations per season.
Potato leafhoppers have leaf-sucking mouthparts. They suck juices from the potato plant causing the veins to turn pale and the leaves to curl. After a while, the the edges of the leaves turn yellow and suffer from a condition known as ‘funnel burn’, which stunts the plant and limits yield.
Insecticides work well for these pests as well. Tackle the crop the first time you find a nymph dispersal. Spray plants with multiple uses insecticidal soap spray, such as Bonide’s. Keep a close eye on the foliage from mid to late May.
3. Aphids
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It is a rare gardener who does not know aphids. These common vegetable pests they are small and green or black and are found in clusters on the underside of leaves. Adults turn into demons in the spring looking for an acceptable plant, such as a potato plant, to eat.
When they find one, they immediately move in and take up residence, losing their wings, sucking juices from the plant, and giving birth to another generation that quickly begets another.
No plant does well when its plant juices are extracted. The potato plants are wilting and crops are destroyed. Look for light green spots on the upper leaves and curling of the leaf margins. At this point, tuber yields can drop by up to 60%.
The sustainable integrated pest management solution: enter natural enemies of aphids. My favorite is the ladybug, but other less “cute” bugs also work, such as lace larvae, hoverfly larvaeand parasitic wasps. Do not use pesticides on other pests, however, because these predators are very sensitive to insecticides.
You really can buy ladybugs to attack aphids on amazon.
4. Wireworms
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Wireworms they are beetle larvae and look like small pieces of wire. They are thin, yellow-brown and about 1 inch (2.5 cm) long. They are hungry during potato seeding and will feel on the seed pieces immediately after planting. Their population is higher if your garden was previously a lawn or was fallow the previous year.
Test for wireworms by burying a handful of raw wheat, corn or potatoes in the ground about a month before planting. Mark the location, then 10 days later, dig up the bait and take a look.
If more than one wireline is found on the bait, take action. If you don’t act, wireworms will feed on your seed potatoes, seedlings, and even your tubers. One way to combat wire ropes is to trap and kill them.
Take pieces of raw potato and then “plant” them in the soil. Check the traps weekly and collect and kill any wireworms on them.
Common potato diseases
That’s not all, guys! Even when you do everything you need to do to keep insects away, your potato plants can fall victim to some common potato diseases. To locate them, you do not need to dig up the tubers. They often appear first on the foliage. Here are the four most common potato diseases to watch out for.
1. Late blight
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Potato late blight it is one of the most critical diseases to be treated. It is caused by a fungus that can infect foliage, stems and tubers. It can also spread throughout the garden in the wind. Look for irregular dark spots that get bigger over time.
On the upper side of a leaf, the dark area is surrounded by a green halo, and on the underside, you may see white mold. When the tuber is infected, you will see dark brown or purple spots.
The best way to control of potato blight it is a comprehensive approach. Start with a potato variety that has some blight resistance, eg these ‘German Butterball’ tubers from Burpee. It is also vital to keep sources of the fungus, including other infected crops, away from your potato patch.
Illness is likely when you experience two consecutive days with a temperature of at least 50°F (10°C) and six or more hours of 90% relative humidity. This means that the risk of infection is high. Use a fungicide, such as that of Bonideto prevent and treat problems if you have been experiencing this pattern for a long time.
2. Early Blight
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Potato early blightalso called alternaria, is a soil-borne fungal pathogen that affects a variety of crops. Look for concentric rings of lesions on the leaves that appear a few weeks after the foliage appears. The disease starts as very small spots on the lower leaves that then coalesce into larger spots.
Alternaria causes leaf lesions that often have a targeted appearance of concentric rings. Small dark dots appear a few weeks after emergence on the lower leaves, then grow and kill the leaf tissue.
You can help prevent this disease by removing debris and weeds from your garden. crop rotation can also help. Don’t let your plants get stressed, as stress will increase the impact. If the problem is spreading quickly or affecting many of your plants, treat it with a fungicide like the one above.
3. Common scabies
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Three to six weeks after the potato tubers begin to grow, the surrounding soil should be moist. If these tubers grow in dry soil during this stage, they can become infected common potato scabwhich is an unsightly imperfect disease. Lesions start small and coalesce into larger irregular areas and become colorless to dark brown.
Scab often results from lack of irrigation, lack of light, poor drainage of soils or dry weather. If the cause is simple, so is the solution. Water the potato plants once or twice a week for the first month after tuber initiation. It also helps to use fine texture and well-drained soilplant pure seed potatoes and use crop rotation.
4. Blackleg & Soft Rot
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Crook is an important potato disease caused by many of the same bacteria that cause it soft rot on potato tubers.
Foliage is first affected by blackleg, and then you may see rolled upper leaves, blackened stems at ground level, and reduced pale green or yellow foliage. It can also cause a slimy green-brown rot and the collapse of potato stems. The symptoms of black leg vary depending on the prevailing weather conditions.
In potato tubers, the rot starts from infected wounds, lentils and tips of fleets. Over time, you will also see soft, moist, creamy tissue with a sharp demarcation between diseased and healthy areas. Over time it develops a bad smell.
There is no proven chemical treatment for potato blackleg. Your best bet is to use good cultural practices, such as using certified disease-free seed potatoes, not over watering your plantsand dispose of any infected plants as soon as you discover them.
