Roots - Potatoes
Print
EmailFebruary 27, 2025
More Info
In this “grounded” session, Nicolle Ritchie and Chris Galbraith will dig up some sage advice on going from seed tuber to feed tuber.
Nicolle Ritchie is the MSU Extension field crops agronomist educator working in southwest Michigan. She focuses on pest management in corn, soy, pickles and potatoes, and is passionate about managing resistance, improving soil health and incorporating sustainable practices.
Chris Galbraith is a vegetable educator for MSU Extension in southeast Michigan. His passion is in weed management, soil biology, market gardening and other areas of commercial vegetable production.
The 2025 MI Ag Ideas to Grow With conference was held virtually, February 24 - March 7, 2024. This two-week program encompassed many aspects of the agricultural industry and offered a full array of educational sessions for farmers and homeowners interested in food production and other agricultural endeavors. More information can be found at: https://www.canr.msu.edu/miagideas/
Video Transcript
If you would like to learn more about MSU Extension's Farm Stress Program, you can visit their website by using this QR code or it's canr dot msu dot slash Managing Farm Stress with underscores. Now we're going to get into our presentation today. If you have any questions during the presentation, please drop them in the chat and we're going to go ahead. Chris, the floor is now yours. Great. Thanks, Nicolle. Good morning, everybody. My name is Chris Galbraith. I'm a vegetable educator with MSU. I cover Southeast Michigan for MSU extension and Northwest Ohio for Ohio State University Extension. Yeah, the topic of today's presentation is going to be growing potatoes. We'll talk about some of the different considerations to keep in mind when you're growing potatoes here coming season. So all right. So the outline of this presentation, I'll start off by talking a bit about some of the horticultural practices related to potato production, namely planting, fertilizer, irrigation, harvest, and storage. Then Nicolle will take over the second half. The majority of this presentation will be about pest management. So diseases, insects, and weeds, other forms of crop protection. So that'll be the structure. To start off with a little bit of botany. Potatoes are in the Solanaceae the nightshade family. Also other vegetable crops in the nightshade family include tomatoes, peppers, eggplant, tomatillos, that sort of thing. Tobacco, not a vegetable, but also in the nightshade family. Many weeds in Michigan are also in this family, horse nettle, gymson weed, Eastern black nightshade, and so forth. Potatoes their species name is solanum tuberosum and solanum being the genus, tuberosum being the specific epithet. That's the botany. Next slide, please. You may be familiar with the name Nikolai Vavlov. Vavlov was a Russian Soviet economist, a scientist, and he's famous for characterizing these different centers of origin where different crops that we grow today were originally domesticated. So these biodiversity hotspots, such as potatoes were domesticated and originally grown in the Andes region of South America. Think Peru and Bolivia. When the Spanish came to the New World, they brought the tubers back to Europe where they caught on. Then Europeans later brought potatoes to the New World to North America rather in the 18th century and they've been grown in America ever since. Next slide. Michigan, you may not know, but Michigan has a pretty sizable potato industry. In fact, we're the eighth in the nation in terms of potato production. Potato industry contributes around 2.5 billion dollar to Michigan's economy annually, creates around 22,000 jobs, and in terms of acreage, 70% of the potatoes that are grown in Michigan are for the purpose of making potato chips, okay? Just one more point on that last slide, please. 85% of the potato acreage in Michigan are white potatoes, 13% are russets and one to 2% are red and yellow specialty type potatoes. This information was taken from an economic report that the Michigan Potato industry put out. You can see it on the left hand side there. Also, MSU was involved and that information is available online. So this is a good time to talk about different types of potatoes. So you're going to be familiar likely with russet potatoes. This is sort of your classic baking type. It's sort of oblong, darker brown skin. It's mainly grown for like table stack purposes. So, you know, it's used for french fries, for example. Chipping potatoes are going to be rounder and smaller. Think of a baseball in terms of size and shape. Again, those are going to be peeled and baked into potato chips. Then we have our specialty type potatoes that come in all the different colors, reds, yellows and so forth, and again, mostly going to be used for table stock. They really benefit from being grown in high organic matter soils to give the skins their color. As far as the plant biology for potatoes. Potatoes originally are grown from seed tuber, aka the mother tuber. From the seed tuber, we get the above ground growth, stem, leaf tissue, flowers. Potatoes do flower and produce fruit. The berries, which are not edible. Below ground, we have the stolon and tuber production. Next slide, please. This diagram shows the life cycle or growth stages of potato plant. Again, we start with our seed tuber, you get the sprouting of the above ground growth. You get hilling, we'll talk about later, but basically you're keeping the tubers below ground growth buried. We'll talk about that later. Tuber initiation is when the stolons begin to form the tubers. Around the time of the plants flowering, the tubers really begin to bulk up and they continue to bulk up until the vines eventually decline. Then you would harvest shortly after. This diagram was taken from the Ontario Vegetable Guide, which is also free online and you can see on the bottom there the different times of year when you would expect to see these different growth stages. These are photos from Nicolle. It shows tuber formation, as I mentioned. You have your seed tuber, the buds, the eyes on the tuber begin to sprout. You get stolon development, root system formation. Those stolons as they grow will start to hook at the end. This is the start of tuber initiation basically. The hooks begin to swell and you'll get the tubers forming eventually around the time of the plant flowering, as I mentioned, they will begin to bulk up. It's a good idea to start with really high quality seed that is disease and virus free. Potatoes are typically planted from the seed pieces. You'll have a tuber and cut it up into smaller pieces, each with at least two eyes on the seed piece. Again, the eyes are growing points, buds, right? So if you're cutting up your tubers into seed pieces yourself, generally, you're going to want to let them heal for a few days at room temperature and just let them heal before you plant them. Also, you're going to want to avoid planting sweaty seed. If the seed pieces are sweaty, again, let them acclimate at room temperature before you plant them. On this diagram on the bottom, also from the Ontario Vegetable Guide, it shows the ideal seed piece shape. You have a few different eyes on the seed piece. Right next to it on the bottom there you can see what we call a blind seed piece, which has no eyes on it and so it has no means to grow. Then other non optimal shapes as well. As far as planting guidelines, generally three feet apart between row spacing is a good configuration. If you're doing it on a garden scale, it can certainly be less than that. In row spacing, about nine to 11 " between plants and for about four to 6 " in depth. Once you plant your potatoes, generally, you can expect them to be mature, around 90 to 120 days days to maturity. Soil type is an important element when it comes to growing potatoes. Generally, they're going to prefer a loose, well drained soil, like a sandy soil, and that's because the tubers really need to be able to breathe and easily displace the soil as they are growing. So If you think of soil particles in terms of their different textural classes, you can see there that beach ball would be more like a sand particle in size compared to a silt particle, which is smaller, which would be more softball sized in that scale. Then a clay particle is going to be even smaller, think like a ladybug in comparison to those other two textural classes. On the right hand side, another photo from Nicolle, you can see tubers. The right hand tuber with smiley face was grown in a well drained soil and so we have a normal looking tuber, on the left is one that was grown in a soil that was not drained particularly well, and so we have enlarged lenticels, those white areas. lenticels are like sites of gas exchange on the tuber, and if the soil type isn't quite right, you can get that sort of uh phenotype. Anyway, it's a good idea to get a soil test done to guide your fertilizer program. MSU Extension offices, we sell soil test kits for commercial and for, lawn and garden. This is what it would look like for a commercial soil test results. For gardens, it would look a bit different. But basically on the top there you can see, you can see the background information or where that would be. Then below you would have soil test results. This will give you info on your pH, your phosphorus potassium, magnesium, what that looks like in terms of optimal levels, calcium, data exchange capacity, organic matter, and then also any micronutrients if you get those tests as well. And it will also give you your recommendations. How much lime to add, say, in order to manipulate the pH. Macronutrients, how much to add for a given yield goal. Same with micronutrients. This example is for a deer plot, but it would look deer feed plot, but it would look pretty similar for potatoes or other crops. These screenshots were taken from an MSU article. The anatomy of a soil test report, which is available online, walks you through how to interpret your soil test results. You may have heard that soil pH is important when it comes to growing potatoes. Potatoes really like a slightly acidic soil. 5.5 to 6.5 is generally the range you're shooting for. And the benefit of that is that potatoes are less susceptible. There's less incidence of scab at that slightly lower pH. Scab is a bacterial disease that Nicolle will be talking about a bit later on, I believe. One more point on that last slide. You can get some nutrient availability issues, particularly when it comes to phosphorus at the lower pHs, but 5.5 to 6.5, generally potatoes do pretty well. Fertilizer, nitrogen and potassium are going to be your biggest nutrients that you're going to apply. Nitrogen is very involved with vegetative growth, of course, and you want to be careful not to overapply nitrogen because you can get excess vegetative growth, which causes a few different issues, including greater risk of foliar diseases with all that over vigorous vegetative growth. You just want your nutrients to be balanced, of course. Other important nutrients would be phosphorus, which is involved with root development. Calcium, which is involved with cell wall development and general storability of the crop. Boron also is involved with cell wall development. Some real general fertilizer recommend guidelines. It's going to be based on your soil test, of course. But before planting, generally, you'll apply and incorporate all the potassium based on your soil test. At planting, you can apply nitrogen and phosphorus and you can side dress nitrogen a few times early on in the season as well. An also an option is applying micronutrients through folier applications throughout the season as well if needed. Irrigation. Okay tuber initiation, as we saw earlier, that's going to be a time for peak water use with the plant. After that, generally slows down after the tuber is around nickel sized. Like most vegetables, potatoes are going to do well with 1" of water per week. Lots of different ways to irrigate potatoes. On a larger scale, it's going to be a lot of center pivot irrigation or real guns. You can do sprinklers, drip tape is not super common, I think because it gets in the way of hilling. But it is good to be mindful of leaf wetness because wet foliage can certainly cause foliar diseases to be more of an issue. I mentioned hilling. The purpose of hilling, and again, hilling is basically just mounting the soil up around your plant as it grows up around the base of it. The purpose of hilling is to keep those tubers underground and blocked from exposure to sunlight. It also helps increase overall stolon and tuber production. Yeah, generally, a system or a setup like that photo there with the discs angled to collect the soil up around the plant is used. You can also form your hills and then plant into them later on. Just be careful not to damage the root systems when you're moving that soil around. Harvest. You can harvest potatoes earlier in the season before the plants have died. These are known as new potatoes and they're generally best for fresh market sales because they don't store particularly well. Tubers aren't mature yet, and so their skin isn't as thick, they don't store as well, and they're more sensitive to machine harvest. Mature tubers are going to store much better, you're going to have thicker skins and Generally you'll harvest mature tubers two to three weeks after the foliage has died off or on a commercial scale been desiccated. Harvest. It's going to look pretty similar, whether you're using a machine harvester or you're doing it by hand, the steps are similar. You're going to dig the tubers, you're going to sort out the soil from the tubers. You're going to remove the haulms or vines that are still connected to the tubers, and then of course, loading and taking them to storage. Potatoes do require a curing step. Basically, this is when the tubers heal from any nicks or bruises they suffer during harvest, and they also the skin thickens up a bit more as well. And so 59 degrees Fahrenheit is going to be a temperature that you're going to see the best healing or most rapid healing. It's generally recommended to keep the tubers at that temperature for ten days or so at the beginning of the storage period and then gradually lower that as you get down to your desired storage temperature. And just to maintain dark and well ventilated conditions, of course. Then just a few thoughts on storage. Generally, 40 degrees Fahrenheit and 99 degrees relative humidity is going to be best quite humid. The main risks in storage is going to be dehydration of the tubers, sprouting of the tubers or post harvest rots. It's generally recommended not to wash potatoes before storage as that can cause reduced storage life. Okay. That's all I had for the first part here. Nicolle will take over and she'll talk more about crop protection and pest management. Awesome. Thanks, Chris. Yeah. This is my favorite thing ever. I love talking about this. You might have heard potatoes, as far as pesticide applications are actually pretty high up there and that's because there are a lot of major pests that affect potatoes and they affect them very badly. There are a lot of preventative applications that are going out to try and reduce the instance of pests. Then there are a lot of curative things of, we've seen a problem and now we're going to apply it to try and keep the problem from getting worse. We're going to start with diseases here. Really important to know, first of all, what contributes to disease. Obviously, you want the right environment for the disease to be able to grow, otherwise, it won't grow. You have to have the pathogen or else there won't be a disease, and you also have to have the susceptible crop. If you're growing potatoes, that's your crop. Then your pathogen may or may not be present and the environment will often depend on weather, but it can depend on a couple of other things too. One thing that really contributes to disease in potatoes is leaf wetness and Chris mentioned this earlier, and that's because pathogens tend to love moisture and they need that to be able to reproduce. Potatoes tend to be a pretty thirsty crop, so there's a lot of water being applied, and then they get this really thick, nice canopy and that canopy traps water or moisture humidity under the leaves, and it reduces airflow. That can be a really big factor for creating disease environments. So when it comes to any pest, how do you know when you need to act? We're going to be talking about that. We're going to start with diseases. So when it comes to diseases, how do you know? Well, first of all, you want to make sure that you're checking on your plants, and that's a lot easier maybe as a home gardener with a few plants to compare to a commercial grower with thousands of acres. But either way, you need to find a system that works for you. This is a picture of me. I used to scout potato fields and they were commercial fields. They were large 100 acre fields, and I would go around on a four wheeler and I would check and I would walk out into the fields and watch for things. It's just really important before we're even looking at applying anything or taking action, we need to make sure what's actually out there and how our crop is doing. I've put up here the most economically important disease. This is late blight. It was responsible for the Irish potato famine, highly destructive, highly contagious. It's a really big deal. I've got over here some pictures that show you what it looks like. Basically, we're looking at these dark lesions, black that don't have a super defined edge. Then if you flip the leaf over, you might get this silvery fuzzy carpet of spores on the backside. That's what late light looks like. It is highly contagious. It travels on water, so that can mean it travels through fog or humidity in water in the air. It could also travel on individual plants through water, and of course, it can also travel on your shoes or your clothing if you've been in an infected field and you're moving around. So in the commercial fields, pretty much at least half of the pesticide applications, probably more, are going toward preventing late blight infection. So a lot of preventative fungicides to keep it from coming into the fields. Homeowners don't really have that option. For one, a lot of these preventative pesticides are not available to homeowners or smaller growers in the same way they are to commercial growers, and they can be restricted use, which means that you have to have specific licensing to use them. So as a home grower, what can you really do? You just want to make sure you're keeping a really good eye on this. So a lot of times late blight spores are in an area and those spores might have passed over a commercial field, but because a commercial field is receiving those preventative fungicides, nothing took hold there. But if the spores reach, let's say, a home gardener's plant, then they might decide to take hold there. They might be able to get a hold there and they can continue to multiply. Just something, especially if you're a home gardener, really watch out for this because it can not only impact your potato crop, but it can impact everyone in the vicinity if you're not careful. So if you have any suspicion that it's late blight, you think that it might be, if you think that it looks like these symptoms or you're concerned about it, definitely say something. Reach out to somebody. There are diagnostic labs available. A lot of times, people with experience, if you even just send a picture can give a decently good diagnosis from a picture. Just make sure that you're saying something and that you're watching out for that. In fact, in Southwest Michigan anyway, where I'm located, a couple of the farms here will actually pay for your diagnosis to make sure that it's not late blight. So say something, even if you're not sure how to go about it, you can reach out to someone like Chris or me and we can get you to the right resources just to help make sure that that's not spreading because it can be a really destructive and contagious disease. Now, Botrytis is something that's going to look pretty similar to late blight which makes it difficult. The only reason I put it in here is because it can look similar. But it's actually extremely common and it doesn't do any economic damage. It might minorly affect your crop, but it's really not something to worry about. The only reason it's in here again is because it can sometimes look like late blight. Just keep an eye out for that. Then we have another disease called early blight. We have late blight. This is early. You can guess that it probably shows up a little earlier and you'd be right. Generally speaking, that is the case. What you want to watch for with this is there will be these lesions, they look metallocky and they have these defined edges, and then they have what we call concentric rings. Now sometimes that's a really obvious concentric ring. It's like a spiral within the lesion and sometimes it's a lot harder to see. Early blight might be a big deal. It really depends on a lot of things like what stage your crop is at, and most importantly, how much of that leaf is covered in the lesion. When we're getting a large leaf percentage of lesions, that's reducing how much photosynthesis can occur and that's not a good thing. Again, the action threshold itself would depend. There are some chemical options that help halt the progression of early blight and can increase your plants ability to to fight it off. You'll probably see it at some point. Most of the time, it won't be a huge deal, but it might occasionally. Here I've just put a core drawing of those concentric rings, that little spiral inside the lesions, that's a very clear mark of early blight. Another thing you might see is white mold and that goes back to this canopy, it has a lot of water, it has a lot of moisture, and it doesn't have a lot of airflow. White mold is actually, it occurs in soybeans. If you're following a soybean crop, for example, you might have an increased risk for white mold. Um, it's essentially this white fluffy growth that occurs on stems and leaves, and for the most part, it doesn't cause a big problem in potatoes, unless you see it on really healthy tissues and it starts killing those, then it can cause a problem. It could lead to vine collapse and stem death. For the most part, you might not even see this, especially as a home gardener, but it's just something to be aware of. There is no way to cure it. If you get white mold, you're pretty much stuck with it. The only options are prevention. You can do that by choosing good genetic material. You can do that by choosing fields where white mold doesn't have a history. For most home gardeners, it probably doesn't, it's more likely to occur in soybean fields because those can harbor white mold. Then really the most vulnerable time for a potato is when it's flowering and that's basically an open door for pathogens and especially white mold often will send out its spores at that time. It can enter the flower and then it can enter the plant. If you're looking to prevent it, then you would need to be taking action right around flowering or during flowering. All right. Here, it's a disease, but it's not a disease. It's a complicated thing. It's a complex is what we call it. What this is, it's called potato early die. It's pretty much just like it sounds. It causes early death of potatoes. You don't want your canopy to be melting down. We call it melting down. It's thinning out, it's getting yellow, it's reduced photosynthetic capability. What causes this? It's caused by these nematodes in the soil, little roundworms, specifically a root lesion nematode, and it will chew on the roots and open up openings for this pathogen, verticillium dahliae to enter the plant, and then once it's in the plant, it will start to proliferate. In the stems, it multiplies and it gets bigger. The more potato crops you have, the worse risk you will be at for potato early die, and especially if you have them in close succession. So that's one of the things that you can do is to rotate your crop to try and reduce the instance of potato early die. You can also try and reduce nematode populations. This gets tricky though, because most nematodes are restrictive pesticides, they're highly toxic and you have to be very careful with them. And it's just not realistic for, let's say, smaller growers or homeowners to be using that. Of course, you can also try to reduce how much verticillium dahliae is in the soil. Again, that comes back mostly to crop rotation. Now, you've survived the growing season, you've harvested your potatoes, you survived all the diseases during the season, but the work is not done because there are still other diseases that can occur. Your tubers might have diseases as you're harvesting, you'll see that. One of them is potato scab, as Chris mentioned earlier, this comes from a bacteria and it really affects the skins obviously and especially those thin skinned varieties can be really susceptible. If you are in an area where you might be at higher risk for scab, you can choose thicker skinned varieties to hopefully help reduce that. scab does not like acidic soil, so that's another option you have in your toolbox is to reduce the pH of your soil. It is important to know, even though this is ugly, it is still edible. You can just peel the skin and you'll be fine. But obviously, if you're trying to sell your crop, we always say consumers buy with their eyes. You want your potato to look really pretty and this is something that would get in the way of that. There are also a couple of viruses, but we're just going to talk about one that can affect potatoes. Potato virus Y can affect potatoes. This is really a problem if you're trying to produce seed, and that's because the virus will spread to daughter tubers. In asexual reproduction is what we call it like that cloning of the tuber, it will perpetuate. We'll still have the virus in each generation. If you have sexual reproduction, like if you grow a potato from a potato seed from that little green useless fruit, not useless, but not edible fruit. Then you probably won't have the virus, but you'll have a lot of genetic variability. That's something to watch out for. Really, with a virus, there's not a whole lot you can do and especially after it's been infected, your hands are tied. Prevention is the best thing on this. Make sure that you're planting good seed that has been verified that it doesn't have virus, and then make sure that you're reducing your aphid populations. I'll talk about aphids in a minute. But there are these little insects and what they do is they can carry the virus around and transmit it and that's how it travels. Now, you've harvested everything. It's looking good, you put it in storage and things can still go bad. Potatoes are basically balls of water, their high water content, and we don't want shrively potatoes. That means that if you want your potatoes to maintain that, we call it turgidity, so that really nice firm flesh, then you need to have pretty high moisture, high humidity. And we talked about pathogens love humidity, they love moisture, this can open up all sorts of problems. Now Chris talked earlier about those lenticels and those were those white little puffy spots when they get wet, they will burst, actually. They're just trying to breathe. The potatoes are trying to get oxygen and airflow. Those lenticels, when they burst, that becomes a wound and that wound is an open door for pathogens. A lot of these harvest rots really were happening in the field and you just don't see it until conditions are right after harvest. That's something to be aware of. I Honestly, you'll smell them. They don't smell great. You might see them. They might have this really fuzzy external growth, like seen in this picture here, you can squeeze them and liquid will come out and that will actually help you diagnose sometimes what kind of rot it is. But ultimately, when they're this far gone, there's not a lot you can do. You can try to prevent rots, by reducing your temperature, keeping it like a refrigerator cold. That's going to slow down the growth of pathogens. You can also use moisture and ventilation to try and help reduce the risk of rot in your storage potatoes. This is a slide that Chris put together here. This is just a really nice summary of not all the different, but the major rots that you might see. I won't go into great detail on them because basically, if you see them, It's a little too late, but just be aware that that's something that could be happening to your potatoes. All right. Now we're to the insect part. This is my favorite part. I love insects. This tricky little bug, it's not really a bug, it's a Colorado potato beetle. They are these orange little beetles and they emerge from the soil in the spring, these adults and they mate and they lay eggs on the undersides of potato leaves. Then those eggs hatch and they become larvae and the larvae grow and the bigger they grow, the hungrier they grow and the harder they are to kill. There are a couple of concerns with these, one being that their populations can grow pretty quickly, they can very quickly cause damage to potatoes and it can be very difficult to control because when it comes to chemical resistance, they actually have this really great detoxification system and they can very quickly gain resistance to chemical products. So that limits the tools that we have in our toolbox for their control. It's really important to use not just chemical strategies, but all sorts of things. For example, these are very lazy fliers. They will just prefer to walk, and you can use that to your advantage. You can create a trench and line that with plastic and it has to be at least 6 " deep, but they won't be able to climb that trench and they'll just fall down. So they'll fly and sometimes they'll just give up like, all right, well, it wasn't meant to be, which is funny? That is one example of a cultural control that you could use to try and reduce these populations or rather reduce them being in your crop. Obviously, if you are on small enough acres, you can just go out and physically pick them off. If you see those orange egg masses, squish them, don't leave them. Don't let them continue to develop. You might be able to use a hose to spray them off depending on what stage they're at. There are lots of chemical options available as well. Most of them are not necessarily available to homeowners, so that's something to watch out for. Like I said, they're very quickly gaining resistance, something that worked maybe even ten years ago might not be as effective now or effective at all depending on what kind of population you have. Then there are some biological control options. There are a couple of fungal infections that can affect bees and there are also insects that will feed on them. This is a Colorado potato beetle larva and it's being preyed on by a spined soldier bug, which is a type of stink bug. That's really awesome. We want to see that. We want to make sure that we're conserving these populations of insects that will prey on potato beetles. But we also need to recognize there are some limitations. For example, this Spine soldier bug, it might take it multiple hours and even all day to eat a large larva. Then what do you do? It's full. How many more larvae is it going to eat? It can just be a very slow process and these tend to reproduce very rapidly, the potato beetles. You saw that large cluster of eggs, so that's a lot of larvae coming out of there. Just something to keep in mind, there are some natural predators. It might not be a catch all. It might. It really depends on the population. But as much as you can, do what you can to conserve these predator populations and keep them in your crops. Another insect is the potato leaf hopper. This is one of those tricky things of after you see damage, it's too late. Basically, there's these little tiny green bugs or insects rather. You can see them circled here, very small and a bright green. They fly in early summer and they feed on the plants and can cause hopperburn is what it's called. It's basically where these leaves start to turn yellow in a V shape and By the time you're seeing hopper burn, there's nothing you can do. The insects have moved on, the damage is already done to your potatoes. Before that occurs, you want to be out checking on your plants. Again, it's so important to be out in your fields. You can use what's called a sweep net. There's a picture of the net here and you can look up videos online to see how to do this. But basically, you sweep it through the plants, and then you check and see what kind of stuff you caught. And as a minimum, in a commercial setting, as a minimum, you would sweep 25 rows in three different spots in the field, and if you have even an average of one leaf hopper per net or per sweep, that's a problem or per location. So Something to watch out for as a homeowner, is this really realistic? No, probably, you're not going to have a gigantic leaf hopper population. They're really going to be looking for something larger in general. You might get them still on your crops and you can spray them off or you can squish them. They are very small though, so keep an eye out for them. Aphids, Aphids can cause a lot of problems. As we talked earlier, they can transmit viruses, which is very problematic. There are actually lots of different types of aphids that will affect potatoes. There are just a couple though that are really significant. The tricky thing with aphids is that their populations can build very quickly. Over here on the left, we have a picture of an aphid and it has wings. On the right, we have a picture of aphids, but they don't have wings on them. These winged aphids will fly around and they're really looking for, what is a suitable host? Where is a place that I could raise a have a family basically and that would provide all of my nutritional needs. It's going around and it's got this proboscis. Maybe you can see it tucked under its head and it's testing out every leaf. It's coming to something that might look suitable and it tries it out, tests it out and decides if it likes it. Now that's really bad for transmitting viruses because that means it's touching all sorts of plants and then going over and touching more plants and traveling a great distance if it doesn't find what it's looking for. Now, there are also these wingless adult aphids and they reproduce very quickly. In fact, they're basically producing clones of themselves and basically large live birth and their populations can build very, very quickly, and the more aphids there are per leaf, the more juices they're sucking out of the plant and the more rapidly your potatoes canopy could be affected. What do you do with aphids? I think this is the The time old tail. What do we do? These have been problems for a very long time. If you're a small scale grower, you could spray them. Obviously, these wingless adults and young, they're not very mobile. If you spray them off and are able to remove them physically, you probably have a pretty good chance of that working. Control wise. Another option is there are chemicals that are available. Something you have to be really careful with if you're using a chemical option is that these aphids are very low in the canopy and you need to make sure that the spray can actually reach them. They're often on the underside of leaves, which makes it even more complicated. Then there are also horticultural oils that you can use. Basically what this does is it just makes it an uncomfortable environment for these aphids. They decide, I don't know if it's worth it, this doesn't feel right and it changes the leaf environment for them enough that a lot of times they'll decide, this is a lot of work for me, I'm going to go somewhere else. Now, weeds. Weeds are a huge problem in every system and actually, I'm not going to spend a lot of time talking about specific weeds, but it is really important to know that potatoes are very sensitive to herbicides. Here we've got this picture and you see these yellow potatoes and you might think, Oh, that was just the sun coming over and that's the sun shining on the plants. But it's actually herbicide drift from a neighboring field, and the potatoes were very sensitive to that. You see it show up very clearly. So what you want to do to avoid that, as much as you can, control your weeds prior to potato emergence. And then understand that when the potato canopy closes, that will shade out a lot of weeds, which should help with control. But by the end of the season, your canopy will open up again and that will open up the potential for weeds again. So keep an eye out. As far as weed control options, there are chemical options. You can do a broad spectrum burn down on existing weeds before you even plant. You can use there are some pre emergence labeled for potatoes. So you could incorporate one of those and try and keep weed seeds from emerging. Now, why doesn't that stop potatoes? Because potatoes have this relatively large seed piece. It's not even a seed. It's a potato. That's a really big carbohydrate reserve. Even if they run into a chemical, they can push through that even if they are very sensitive to it. You might see the results of that though in your tuber. Later, it might be misshapen or cracked and things like that. That's one of the common results. So most importantly, as I've been talking about these chemical options and as I'm talking about them here, always comply with pesticide labels. It's not only important for the environment, it is the law. You are legally accountable for that. Read the label before you buy it, read the label before you apply it. You can remember that because it rhymes and be very conscientious that you're following the rules that you're supposed to be following. Now, if you do use a chemical, be aware that some of that might persist in the soil and have restrictions on crops that you can plant the next year, and that will all be on the label. That's why you need to read it. Then of course, there are lots of cultural ways that you can control weeds. Cultivation has been used for centuries, to help reduce weeds. Then mulch. If you get a nice thick layer of mulch, you can actually do a really good job of keeping weeds down and it will reduce how much greening you're getting on your potatoes. That's a win win. Now, we've talked about all these pests and if you find a pest and you're not sure what it is, or if you'd like to learn more about it, you can actually send a sample or a picture to the MSU Diagnostics lab. So I just want to put that out there that that is a resource for you. Now we've talked about all these pests and really the future of potato production is focusing a lot on pest management, a lot of genetic material, how can we reduce the plants ability or increase the plants ability to fight off disease or to not be very likable to these pests, right? And then there are also a lot of advances being made to try and reduce how much nitrogen potatoes use and how much water they use because those are both things that affect the environment. So the future of potatoes might look very different. We might be talking in ten years with different control tactics than we are now, and hopefully that's a good thing, but it might be small progress too. Just something to keep in mind that this genetic future of potatoes is hopefully going to be a lot better pest management wise. So we'll wrap up with some conclusions here. What are our top tips for successful potato production? First, start off with good seed. You just cannot recover if you don't have good seed. Plant it right. Then prioritize potassium and nitrogen. Make sure that your plants are getting enough water during tuber initiation. That's the time when they're the thirstiest, that's the time when they need it the most. Then keep an eye out for these pests and especially late blight and Colorado potato beetles have the potential to really, really impact your potato plants and your yields. Then finally, after you've done all of that, make sure that you do store your potatoes well so that you can continue to enjoy them and that they don't rot or shrivel or whatever in storage.