Talking all things horticulture, ecology, and design.
Welcome to the Good Growing Podcast. I am Chris Enroth, horticulture educator with
Chris:University of Illinois Extension, coming at you from Macomb Illinois. We have got a great show for you today. It is, oh, what would we say, mid fall. Maybe we're getting a delayed fall time frame, but the questions still keep showing up.
Chris:And so we are gonna cover some of those fall questions that we have been dealing with lately. And you know I'm not doing this by myself. I am joined as always every single week by horticulture educator Ken Johnson in Jacksonville. Hey, Ken.
Ken:Hello, Chris. Certainly doesn't feel like late fall.
Chris:No. It it does not. I have been wearing shorts. I'm wearing short sleeves today. It has been very warm out.
Chris:And, I I I'm saying this as someone who just got back from Florida where I was enjoying 80 degree weather. So it's warm here. Yes. Ken, what'd you do while I was gone?
Ken:I don't know why I wanted to stop.
Chris:It's not it is that doesn't feel like fall. It's not good bonfire weather either. I mean, you you go outside at night, you're like, oh, it's warm outside. I don't I don't wanna sit by a fire. Gross.
Ken:And you may have a sunburn over the weekend. That's just because it was sunny. It had nothing to do with temperatures. But
Chris:You can get sunburn on a a mountain. You know? So yeah. Yeah. I it it has been mild.
Chris:We've had frost, but we have not had really, like like, everything coated in frost or a hard freeze. That's definitely has not happened. So I still have tomatoes growing. Like, we just picked a bunch of cherry cherry tomatoes for our salad that we made the other night. I had some poblano peppers, which I thought, oh, they they were flowering in maybe September.
Chris:And I thought, well, those things aren't gonna make it. So far so good. And looking at the extended forecast, it looks like we'll be okay. We're gonna get down to the thirties a few times, but, you know, I so far so good. It, things are still jamming along here in my yard.
Chris:And, actually, do you remember I don't maybe we didn't talk about this on the podcast, but we had grown a couple, unusual things, one of them being, an African, pumpkin. Is that where we're growing? Some kind of jelly melon. That's what it was. Yes.
Chris:And, it just sort of did you got a big vine, right, on yours? Do you ever get flowers?
Ken:It did put out flowers. What was that? September? I haven't I just kinda wrote it up like, oh, we're gonna get a frost. There's no point in checking.
Ken:I haven't checked with suns. I need to do that. I completely forgot about that flight.
Chris:You should go check it because mine and my backyard, I have this little thorny looking ball forming on mine, this little thorny fruit. So it go check yours. You might be, pleasantly surprised, but watch where you you touch because they look pretty gnarly.
Ken:Yeah. I'll also do that tonight. Yeah. I mean, we got the same thing in our in our garden. Tomatoes, peppers, we're still putting on flowers.
Ken:When was it? Like, a month ago, 3 weeks ago when we were supposed to get down in the upper twenties, I went out and picked all kinds of stuff. Even a little green because I figured it's gonna all die. It didn't. Still putting stuff on.
Ken:The only thing in our vegetable garden that is dead is the corn.
Chris:Mhmm.
Ken:Everything else. That's Lava beans are still coming on.
Chris:Well, the corn hit its the end of its life cycle. It's an annual, so it's it's done.
Ken:Yeah. Everything else is still rocking and rolling.
Chris:I'm I'm still picking hog brain beans. I pulled out my lemon cucumbers. I just got sick and tired of those, and I probably took, like, 3 dozen lemon cucumbers and just threw them in the compost pile. Like, no. No more.
Chris:I can't do this anymore. You've given me way too much. I harvested the last of our, acorn squash honey bun, And so we're gonna probably probably eat some of that tonight, actually, with our pot roast recipe, which we did on one of our good growing grow longs a few weeks ago, so people could check out that. I'm gonna replicate that recipe probably this very evening that we're recording. So so, yeah, things are still going, happening, hopping along.
Chris:I guess, is this going to keep happening, Ken? What what does the old Noah have to say about, the predicted forecast for our late fall, early winter time frame?
Ken:Yeah. So Noah came out with their their winter outlook October 17th. Mhmm. As and current, La Nina is starting is slowly starting to develop. So tick typically with with La Nina is we have, warmer than normal temperatures in the South, cooler than warmer temperatures in the North.
Ken:Mhmm. So below below normal temperatures in the upper Midwest, particularly the more western areas. So think like the Dakotas and stuff are typically much colder. Ohio River Valley, sees enhanced chances of where the normal conditions particularly in late winter. But that's just so those are just generalizations that doesn't mean it's gonna be bitterly cold or or really wet.
Ken:But more often than not, that's what happens. So that I guess the official predictions, for kind of Illinois and the midwest, and there's maps of these. We can pop these up so people can see them themselves and and link to the actual press release. I think we've even got a link that's like an hour long presentation on all this if you really wanna get into all that. But for for most of Illinois, we are equal chances of below, near, or above average, temperatures.
Ken:So yeah. It's think probably average maybe. Well, I don't really know how to explain that. So you have equal chances of it being above, below, or normal. So We don't know.
Ken:We don't know. Maybe we'll call that average. I think, like, the far southern tip of Illinois was above average was the prediction for temperatures. And then for like the Great Lakes states, warmer or wetter than average conditions are gonna be most likely. And and if you look at the map, it's it's kind of the Northern Northern Illinois and Eastern part of the state, kind of in that above normal Mhmm.
Ken:Prediction whereas, kinda West Central Southern Illinois are in that, equal chances of average below or above.
Chris:Mhmm. And I I am excited. They keep mentioning the Ohio River Valley. I don't know if people are aware of the extreme drought that they faced this past year. And it was a fairly, how else do you describe it, epic.
Chris:It was a historical drought, which seemed to be happening or localized in just this air little area in Ohio, right there along the river. It was a very severe drought. So I think a lot of weather national weather folks are really paying attention to that, very serious drought that occurred there. So I hope they do get some rain, and I hope I hope we get some winter moisture too because that would be great, I e snow. I would love to see a little bit of white stuff this year.
Ken:That would be nice. And I know we've been in a drought. Most of the state, is in a drought, and then we're recording this Tuesday and it's been raining all day, all night. So I think that's probably probably gonna be over.
Chris:Hopefully.
Ken:I think we're good. 2 and a half. I think we're up, like, 2 and a half inches in Jacksonville, if not 3.
Chris:I think we got, we got our first inch of rain, and then it kinda died out. And I met with a a friend, partner, coworker of of mine, and we were probing soil for tree planting. And we'd go down about an inch and a half, and it we hit dry soil. But that was before we got this extra bit of rain that we've had this past night. So, hopefully, it was a little bit slower, but a good amount of rainfall.
Chris:It was able to to infiltrate into the soil, get that moisture down a little bit deeper, because that that inch of rain that we had initially, it did not penetrate very far, at least in our part of the world here in Macomb.
Ken:Yeah. I think at least for the rain that I've been awake for, has been a a really nice gentle kinda soaking rain, not really hard. Mhmm.
Chris:So
Ken:hopefully, it will make it make it down and then I'll run off. Feels like it was really hard.
Chris:Mhmm. Well, again, I just wanna see some snow this year. We we had, like, one snow event last year, and it didn't take long for it to go away. So it'd be nice to have a little bit of powdery stuff this this coming year. Ken, we have lots of fun, interesting questions that are still coming into our our email inboxes, phone calls, you know, people reaching out to us.
Chris:Even though it is later in the gardening season, most gardens aren't really doing much even though they might still be producing things if you have a vegetable garden. But we've had some questions come in. So, Ken, would you mind kicking us off on this, first question this week, please?
Ken:Yes. So our first one is about roses. So I have David I have a David Austin rose, that has a shoot that is thorny with red growth.
Chris:Yes. This was a a email question that I received, and that that was the information I got. So after a little bit more correspondence, got some some photographs of this particular plant. And again, folks, sorry, we can't necessarily post all the pictures that we get because we don't take them. If we don't take them, we don't have permission to use them.
Chris:So I know every once in a while we'll get those comments like, why don't you post the picture that you're talking about? Well, it's not my picture to post, but I'll ask and see if they'll let me. Anyway, the photographs that I received were the the thorns, which, botanically speaking, roses don't have thorns. They have prickles. Sorry, Brett Michaels, lead singer of Poison.
Chris:You're wrong. Not every rose has a thorn. They they don't actually have thorns, so, they have prickles. But, anyway, we'll call them thorns for today. The the these the single cane or stem of this rose was just it was like a wookie of of thorns.
Chris:You know? It was just covered in them. It was thorny, prickly. You know? It was it's covered in them.
Chris:And then I noticed in kind of the background of this photo, there were other stems kind of lower down on the plant also showing the same thing. And that is a very good sign for a particular deeds disease called rose rosette, and that is a virus. Not always, but but this is a very good indication that's what's happening. So the other I I also we went through a couple other possibilities. You know, we talked about, have you sprayed any herbicide around?
Chris:Sometimes a plant growth regulator can cause some of that wild growth to occur on our plants. They said no, but there are crop dusters nearby, and every once in a while, their their yard gets hit by these things. And so we we sort of ruled all that out, and we started looking at the possibility of rose rosette virus. Now the unfortunate thing when it comes to plant viruses is that there's really no cure for these. We've probably mentioned this on the show before.
Chris:It is a a sad truth of viruses that, the the best thing that we can do when encountering a plant virus is to rogue it out, which in in other terms is get rid of it. You pull it out. You try to remove it so that it cannot spread to any other adjacent plants. And I said, do you have any other roses? And they said, yes.
Chris:We have more than 70 plus roses. So that is a lot of roses. And so we dove into this a little bit deeper. I said, you know, I I I'm pretty certain that this is rose rosette. Since you have so many roses, since you've invested so much money in your landscape on this, it would probably be a good idea to submit one of these to our University of Illinois plant clinic.
Chris:They can sample out, culture and see if this indeed does appear to be rose rosette. Because, you know, Ken and I, we can look at pictures or samples and kinda guess at things, and we can get pretty close with some stuff. But the only way to know, 100%, is to send it into our plant clinic, and that's, it and it really kinda goes case by case basis. I'd love if everybody sent their stuff to the plant clinic. That way, I could confirm or rule out things that I say.
Chris:But that that that definitely, if you have a lot of a particular species that is being affected, it's a good idea to invest the $20, is what the lab fees are, for this, plus the shipping and handling that you might have to pay. So, yeah, rose rosette, which is vectored by a little how do you say this might, Ken? Eryphoid?
Ken:Eryphoid, I've always heard it.
Chris:Eryphoid mite. Yes. So, that that particular mite seems to be the, the culprit of that. Now rose rosette has been around for a long time. Actually, I think they went about 70 years before they really figured out conclusively, like, what is causing the issues with these particular, plants.
Chris:Almost all roses are susceptible to this particular virus. There are known resistant types out there, but I think those lists change pretty frequently, and I'm not hip to the most current cultivars, varieties, restricted use species out there. But but, yeah, there it is it is a disease that is moved by a a small mite, microscopic, really. Can't really see it with your naked eye without assistance.
Ken:Yeah. Really good hand lens. If you're gonna be if you're gonna be looking for those or trying to see them.
Chris:Yep. Yep. And and there's, yeah, not much you can do again once your plant's infected. Rogue it out. Get rid of it so it does not spread to other places.
Chris:Throw in the trash, burn it, bury it, something. Get it out of there. Well, Ken, I think you've been busy while I've been gone dealing with these lawn grubs. I had no idea. So, apparently, there was a string of emails that I saw as I was catching up on stuff, last earlier today, and it was about someone hearing of abnormally high grub activity from lawn care companies and distributors in both Illinois and Michigan.
Chris:It was really just an email to inquire with Illinois Extension folks around the state if they were hearing the same thing. What came of this, Ken? Like, what happened? I'm I'm out of the loop here. Are Grubbs taking over Illinois?
Ken:Yeah. So so for this one, I mean, I've got forwarded to me. And here in Jacksonville, I haven't heard any reports of our complaints about grub activity. I'm not really seeing any in my yard. So, you know, sent it out to the the statewide hoar team and sounds like Northern Illinois, in East Central Illinois, at least people that responded, have been seeing some increased grab activity or getting complaints of it, particularly in the Chicago area.
Ken:It seemed to be pretty high camp. I don't know about Michigan, what's going on here, but at least in Illinois. What we're seeing kinda the increased activity, turf damage happening to these plants. And then John Shevis, hopefully I'm pronouncing his name right. I'm sorry if I mispronounced it, John.
Ken:With PSEF, he's the new entomologist for them. I think he reached out to some people and I'm just gonna read what he wrote. They did a Facebook he did a Facebook post on this, but, now homeowners and lawn care technicians in Central and Northern Illinois are currently experiencing turf issues caused by grub populations. While some have theorized that treatment failures are to blame, the widespread reporting of this issue combined with environmental conditions would suggest otherwise. There's speculation that last year's mild winter may have allowed for a stronger grub population in 2024.
Ken:Additionally, current drought affecting the northern half of the state are likely to weaken grasses. When grass root systems are fed upon by grubs during droughts, it takes less injury to the roots to cause death compared to periods of normal to high rainfall. Grub treatments are not meant to eradicate a population, but rather lower population to a level that will prevent plant death. However, this year, drought conditions have allowed effectively managed group populations to cause turf loss. Basically, mild winter, good chance we had more grubs survive than we typically would.
Ken:And then with the drought, the plants are stressed, those grubs that are there feeding, you know, they're reducing those roots further, inhibiting the plants ability to take up moisture. And you start seeing damage to turf probably much much more than you would typically if we had adequate rainfall. So that was and and again another one too. Somebody working in a in a garden with a lot of native grasses, was seeing a lot of grubs, in there. And they were wanting to know, you know, are these grubs gonna damage the turf grass?
Ken:The or native grass, are they gonna feed on it? And actually came across a paper and we can put this in the show notes, where they did some research. I think this is a group in Michigan and Michigan State University, looking at European Schaeffer grubs. Some of those white grubs we get feeding on turf. They're looking at, some of our our native turf grasses.
Ken:So was it Indian grass, little blue stem tall fescue, and they included Pennsylvania Sedge in there. And then some some turf type grasses, Bermuda grass, zoys are grass, and stuff. And those sha shafers will feed on on the native species, and they can cause damage. And if populations get high enough, they they can kill them or they do enough damage, to those plants. The the turf types seem to withstand the feeding a little bit better.
Ken:One thing I found interesting is that so basically, they're they're doing this experiment in in August. They weren't seeing enough damage so they put more grubs in. And then still weren't seeing enough damage in September and they put more grubs in. And they ended up with densities of 84 and a 182 grubs per square foot. Woah.
Ken:In these spot, there will be the equivalent, in these spots. So I think that's I don't know if you'd ever see populations that high, in the wild, so to speak. So I would say, yes, they'll feed on them, but they had some some pretty pretty high populations in the in those pots. So
Chris:That's a yeah. A lot of pressure, to eat whatever the heck is in front of your face, when you're, shoulder to shoulder or grub to grub here with your friends.
Ken:Yeah. And they and they cut back on watering, so the plants will be drought stressed. So Oh. They're they're kinda doing everything they could to to kill the plants. It's almost yeah.
Chris:Yeah. Interesting. So well, the threshold usually that we tell people when it comes to grub treatment, the number essentially where there's more grubs here that that are feeding than your turf can grow, can can outgrow is it's, like, 10 to 11 per square foot. And that's what what you would dig up a square foot of sod, roll it back. And if you count more than 10 or 11 grubs, that's probably more than your lawn can can tolerate.
Chris:But, again, depends on your weather conditions. If you're encountering drought, those numb that threshold might be lower. And that makes sense. That that does. So when it comes to grub control, I don't know what your options would be this late in the season because grubs, they migrate deeper into the soil.
Chris:They sort of reduce their feeding habits at that this time of year. This might prompt people either either to treat now or to wait until late spring to treat then, I usually try to steer people away from a late spring treatment because there's not it doesn't do anything. The grubs are so big and and meaty and and and your lawn is so vigorously growing, then no one notices each other. It's it's really this late season damage that's that becomes more evident. That's when I typically recommend targeting control time frame, treatment time frame.
Chris:I don't know, Ken. Does that deviate with anything you've heard?
Ken:Yeah. I think, yeah, at this point in the year in November, we're probably too late. Any of the spring, they're at they've probably I think they've done depending on the species, they've done a majority of their feeding already. They'll come out in the spring, they'll feed some, then they're gonna pupate and the adults are coming out, in the summer, late spring summer. So I would say if you've if you had a lot of damage, I would be on the lookout and get ready to treat in the summer or fall when they're laying eggs and those and those larvae are starting to to hatch and feed and stuff.
Chris:And the female, she'll target kind of low cut well irrigated lawn, more lush probably from fertilizers. So, you know, golf courses would be an ideal scenario. A lot of times, they already pretreat, so they don't have to worry about grubs. So if you're treating your lawn like a golf course with fertilizers and irrigation and fungicides and making it brightest, greenest lawn on the block, you and you're cutting it low, you're you're making a nice habitat for grubs, so you have to keep your eye out for them.
Ken:Lay out the welcome mat.
Chris:That's right. The rest of us with our crabgrass and creeping Charlie and dandelions, we don't have to worry as much. Or maybe we we we don't care as much, I guess, I would
Ken:say. That's probably a safe assumption. Yeah. Yeah. Alright.
Ken:We'll we'll stay on that 6 legged bandwagon here. K. So we have question about it's black cherry aphids or or aphids on cherry trees Mhmm. I'm assuming.
Chris:Yes. So this was a particular question. It it was, an email that came with a a photograph, and it was it was obviously one of those, like, I took it with my my phone, and then I text it to somebody. And then through the texting, I got this really small image. So I couldn't really see anything except for a curled leaf, and then I saw in this curled leaf, I saw an ant.
Chris:And that prompted me on a a little, kinda pathway of questions about, well, you know, when do you see this? And they saw this, actually, not this time of year. This was earlier in the year, kinda mid to late springtime that they have seen this recurring problem year after year, and they say it is getting worse. Now what happens in some cases with our cherry trees is there is a particular species of aphids called the black cherry aphid, and it targets cherry trees, namely in the springtime. The aphids, they will actually hatch.
Chris:They're at they're they they overwinter on cherry trees, and the eggs will hatch before they leaf out, and the aphids will start to feed on the buds, the leaf and the flower buds, which will damage them. And then as they leaf out or bud out, they will continue to feed on leaves and such, which then causes curling to occur, which protects the aphids. Within the ant, where the ant comes in, is the ants are farmers of the aphids. The aphids are sucking plant juices out. They poop out sweet honeydew.
Chris:The ants like that honeydew, and so then they will farm those aphids. They will guard them, protect them, from any other predators. So, based on the photographs and the conversation I had with the person, looks like they are dealing with, black cherry aphids. And And the interesting thing is whenever they would finally notice this and go out and take a look in the summer, they couldn't find anything. And that is because when we hit about, oh, about the start of summer, maybe midsummer, the black cherry aphid switches plant host.
Chris:It will develop wings. The next generation will develop wings, and it will fly over to mustard crops, anything in the mustard family, and will feed on that. Females will then when we get to fall, she will come in and lay her eggs on cherry trees then that will overwinter, and that's the cycle. So it is very common when people see this, they look at the leaves. They're all curled up on their cherry tree.
Chris:In the summertime, they can't find any anything. That's because the black cherry aphid has moved to a different plant host. Oh, I I went down a whole aphid rabbit hole here, so it was a pretty interesting species. And, yeah. Oh, treatment.
Chris:Yeah. Let's talk about treatment. What do you do about them? Really, you don't have to do anything. In most cases, natural predators are gonna take care of them.
Chris:But because in this case, there are some times where the population just seems to keep going up and up and up year after year, I did see that in some of the the articles that I read. And so, again, treatment timing is important because they have to be on the plant. And, really, the ideal time is gonna be a delayed dormant oil spray. And by delayed, it means we're not spraying it in the wintertime. We are delaying it till about March to April when the eggs are hatching, but before we're seeing leaf out of our cherry trees.
Chris:So this is all kinda weather climate dependent, where you're at here in in the state or country. And and so making sure your timing that that dormant eye will then suffocate those eggs or those newly hatched aphids and kill them and reduce their population so you won't have as as big of a problem there. And that's that's really it is a a dormant oil spray, few weeks before the tree leaves out or flowers.
Ken:And I wanna plant a cherry tree now.
Chris:You want black cherry aphids. Yeah. I I read that, and I wondered if they are named that because they go after our native black cherry tree, a large tree that grows wild in, Illinois called black cherry. I have to read more about it. Well, Ken, now let let's let's it's like this whole line of questioning.
Chris:Now we're gonna stick to, tree fruit here. So in this line of questioning, I got sent a random photograph from this person with the cherry trees, and they had several different types of tree fruit. And I think they just lumped this in with the group of pictures they sent me, but this one was of a peach tree, and the leaves were curling and blistering. Now this is a question I know, we field quite a bit in the spring, maybe early summertime, but it's actually a pretty good time to talk about this peach leaf curl. Ken, you got a whole article on this thing.
Chris:So is there anything we can do now about peach leaf curl? Because we always get the question after the fact. It's too late to do anything.
Ken:Yeah. So peach leaf curl is is causing those blisters, yellow, reddish, yellowish. It's kind of pretty looking until your leaves start falling off. And fortunately with with peach leaf curl, it's kind of a one and done. You get that initial infection, leaves are affected, and it does not repeatedly infect.
Ken:So if you've got a few here and there, it's not the end of the world. But if you get enough, you can get some defoliation on trees and that's gonna affect your your peach crop and stuff. So this one, fall is actually a really good time. Once pretty much all your leaves have dropped off of the tree, it's a really good time to go in and spray. You can use a copper fungicide or chlorthalidal, as an active ingredient.
Ken:Go on and and spray your trees. Those spores, for peach leaf curl are gonna be on the twigs, the branches, things like that. And they're just gonna overwinter there. So this is one you gotta get really good coverage. That's why we're waiting until leaves fall off.
Ken:So we get good coverage on trees. Make sure you're going around the entire tree, not just spraying one side and then walking away. Better coverage, better control you're gonna have. So you can do that, in the fall. You can also do that in the in the spring before leaves start to swell.
Ken:Once leaves start swelling, those spores can get into the leaves and infect them. So if you if you wait too long, you get rainy weather in the spring, you can't get to it, but it starts swelling or you get an early real early warm smell and those buds start to swell. They may not open but they start swelling that those spores those fungal spores can get in there and infect those leaves. So fall is a good time because you can get that you can get in there and kind of take care of it before you get real busy in the spring or avoid those early warm ups where you have that mud smell.
Chris:Yeah. Yeah. Because that tree should be dormant right now. Dormant. And, I guess the only thing you might be doing is pruning it in the wintertime.
Chris:But, otherwise, yeah, dormant. You'll be hitting everything. Anything that would potentially harbor that particular pathogen, you would be hitting it now in the fall. So, yeah, it's a good time frame to do it. In that way, you don't call us in the summer and say, what's wrong with my peach tree?
Chris:Why am I not getting peaches? Why are the leaves falling off? What can I do about it right now? Because we're just gonna say nothing. It's too late.
Chris:Infection occurred earlier in the year.
Ken:Yes. This is a ounce of prevention is a breath of pandemic here.
Chris:That's right. Yes. Well, that was a lot of great information about things that are popping up in the garden, whether or not it's happening now or people are kind of going back throughout the growing season, seeing things that have occurred, and contacting us, trying to make sure they don't happen again next year. So some timely advice for you, here on our on the Good Growing Podcast. Hey.
Chris:All the Good Growing Podcast is a production of University of Illinois Extension edited this week by me, Chris Inra. Hey, Ken. Thanks for coming back and hanging out with me and chatting all about things, growing or otherwise, what's happening in the garden right now. So thank you, Ken.
Ken:Yes. Thank you. Welcome back. I hope you enjoyed your time away. Mhmm.
Ken:And let's do this again next week.
Chris:Oh, we shall do this again next week. Season extension. Growing vegetables in the cold winter months. It can be done here in Illinois. Ken has done it.
Chris:I have done it. We'll talk to you all about how it is done. Well, listeners, thank you for doing what you do best, and that is listening. Or if you're watching us on YouTube, watching. And as always, keep on growing.