best hydrangeas, browning junipers, birds tapping on windows & more: q&a with ken druse
YOUR RECENT QUESTIONS ranged from favorite blue hydrangeas to junipers with browning needles; birds tapping incessantly on window glass, and tackling the weed Oxalis or wood sorrel. It’s Urgent Garden Question time, and Ken Druse is back to help answer what listeners asked about. Longtime friend and fellow garden writer Ken is author of many books, including “The New Shade Garden” and “Natural Companions” and “Making More Plants.”
Read along as you listen to the August 19, 2019 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on iTunes or Spotify or Stitcher (and browse my archive of podcasts here).
And for those of you listening from near the Capital Region of New York State, Ken will join me at the New York State Writers Institute’s second annual Book Festival on Saturday, September 14th, 2019, and we’re going to have information about how you can join this wonderful, big, free day-long book festival and meet us.
join ken and margaret at 9/14 albany book fair
AN AMAZING, author-filled day is planned by the New York State Writers Institute, on the SUNY-Albany Uptown Campus, on Saturday September 14th, 2019. From Dani Shapiro and Madhur Jaffrey, to Jamaica Kincaid and Joyce Carol Oates…we’ll be part of a group of more than 100 authors and poets participating.
Ken and I will do a Q&A session together at 10:30 AM; we’ll also do individual events at 12:30 (Margaret) and 1:30 (Ken).
Ken will be kicking off his upcoming new book—his 20th!—called “The Scentual Garden,” with a slide talk about botanical fragrance in the 1:30 slot—and though the gorgeous new book doesn’t come out till October, early copies will be available for sale, too. Get the schedule of all Festival events, and the list of participating writers. Come one, come all!
the latest q&a with ken druse
Margaret Roach: New York State Writers Institute’s second annual book festival. September 14th. Me and Ken.
Ken Druse: O.K. It’s a good thing my name doesn’t start with an S.
Margaret: I know, right? That was a hard one, yes. So we’ll be together in real life, and we’re going to do sort of/almost like a version of the show. One of our events that we’re going to do together is like a Q&A kind of thing. Right?
Ken: Only better!
Margaret: Only better, because it’s in IRL, in real life.
parasitic dodder in the garden
Margaret: Yes. So I know that you, because we talked in preparation for today, you had a quick recap on something we’ve talked about before. It’s back, right? Have you seen your dodder? [Above, dodder engulfing a host plant in a Wikimedia photo by Fritz Geller-Grimm.]
Ken: Oh my gosh. You know, you’d say, “It’s back.” I thought of a hundred things that could come back.
Margaret: I know. It’s that time of year.
Ken: Oh, I’m bent over. Yes, dodder. Uh-huh.
Margaret: Yes, we discussed this last August, I think, because it seems like it’s a summer thing. Want to give us just a quick thing, and then we’ll link everybody to how to fight dodder from last year’s show.
Ken: You know, I was thinking it’s too bad everything about dodder, because it’s kind of pretty, in a way.
Margaret: It’s kind of like orange string. [Laughter.]
Ken: And it certainly … It’s unusual, like Silly String.
Ken: It’s orange. It’s slender. This year, it has galls. And there’s-
Margaret: Oh yes?
Ken: Yes. And it’s a parasite related to morning glories, and it is bad.
Margaret: It’s bad. And it weaves in and out of everything. And I think there’s different species that are specific to using different plants as hosts.
Margaret: And oh my goodness.
Ken: You said it weaves in and out of everything. Well it doesn’t.
Margaret: No, it-
Ken: It chooses its target.
Margaret: It does. It picks its host. So it’s pretty fascinating. We have a lot of information, as I said in that transcript from last year. So I’ll give a link because other people have also mentioned that they’re seeing it in their gardens right now.
Ken: I wonder how it got that name.
Margaret: I don’t know. I’ll have to look that up.
Ken: As opposed to “Orange Vampire,” or something.
favorite blue hydrangeas?
Margaret: So a much more optimistic question came from Amy, and was about blue hydrangeas. And she asked do we have a favorite blue hydrangea, and what do we specifically think about the variety called ‘Twist-n-Shout’? She’s in Zone 5B, because that can be relevant to an answer about hydrangeas. So any thoughts over there?
Ken: She’s in 5B. Interesting
Margaret: So that’s like me. And I don’t do well with the big moptop blue hydrangeas.
Margaret: Right? They aren’t reliably hardy, the buds; the flower buds aren’t reliably hardy for me. So, yes.
Ken: You know how you always see them by the ocean, and they look so beautiful?
Margaret: Yes, yes.
Ken: Well I think because the ocean moderates the temperature, the autumn is very long and the buds have time to ripen. So I don’t think it’s necessarily freezing temperatures that gets mine. I think it’s that they don’t ripen cause my season’s too short. But I can’t grow any of the delicious, lovely oceanside varieties of the mopheads, which are Hydrangea macrophylla.
Ken: You know, there’s ones like the one that she mentioned, the ‘Endless Summer,’ that bloom twice. And they don’t bloom twice for me.
Ken: But I do get a bloom the second time because the first set of buds, since they bloomed twice on the same plants, the first set of buds are killed by the winter, but I do get the second set of buds. But you and I both are not the best people to talk about as far as macrophylla because we can’t really grow them. Well, we can grow them. They just don’t bloom. What’s the point?
Margaret: Right. And the ‘Twist-n-Shout’ [a lacecap form] that she’s talking about is similar to that ‘Endless Summer,’ I think, in that, I believe it’s one of those that blooms on old and new wood.
Ken: Right, right.
Margaret: Yes. But so not everybody’s in Zone 5B, and there are other types of hydrangeas and so forth. But what I like in a hydrangea, and if I could grow those, but in any hydrangeas, the paniculata types that are starting to bloom now, in late summer that are much hardier; the oakleaf types, Hydrangea quercifolia; whatever. And some of the newer ones that I haven’t tried that are serrata and aspera species and so forth. [Above, H. aspera var. sargentiana, from Broken Arrow Nursery.]
I like the lacecap arrangements, where it’s not just all those big, flat sterile flowers that can give a hydrangea that moptop, big, big overblown kind of a look. But I like it where it has the little tiny, almost like dots, you know? The little tiny flowers, as well; those fertile flowers.
Ken: Fertile flowers.
Margaret: Yes. So I like that lacecap-y look, no matter what hydrangea we’re talking about, because I love the insect interaction. You know? I love to watch all the bees and everybody else come to hydrangeas, but they don’t come to the ones that have only those sterile …
Margaret: You know, some people call them male flowers, but the sterile flower.
Ken: And they don’t look as natural when you-
Ken: If you want a natural look in the garden, those big-head, baby-head hydrangeas don’t look quite as natural. I love [Hydrangea serrata] ‘Blue Billow.’ I can’t grow it, but that’s a big shrub with those very large lacecaps, and it does have wonderful color. But since we’re saying I can’t grow it, I do have plenty of other kinds. And also lacecaps, especially of the Hydrangea arborescens types.
I know a lot of people grow ‘Annabelle,’ which is a double one, with the kind of round head. But I grow one called radiata, that is lacecap, but it also has silver, or really platinum, on the back of the leaves. [Above and below, Hydrangea radiata, the silver-leaf hydrangea, in photos from Mt. Cuba Center.]
Margaret: Yes, beautiful.
Ken: And if you plant it on a wall or something where there’s a breeze, it just flutters like a quaking aspen. It’s beautiful. And there’s a new one going around called ‘Haas Halo,’ with very large lacecap flowers and dark green leaves. This year, mine is 5 feet tall.
Margaret: Oh my goodness. Well, and again, what’s great about that is it’s a little bit … These are still cultivars; these are named varieties you’re talking about, not just straight Hydrangea arborescens as nature made it. But, they do have some of those fertile flowers in the center, usually, that are of an appeal to insects and can provide some nectar and so forth. So that’s kind of good.
My friends at Broken Arrow Nursery… I did an event there not long ago, and we were walking around doing kind of show-and-tell as part of the day with people at the workshop, and they have an extensive offering of hydrangeas and they love this ‘Lady In Red.’
Ken: Oh, with the red stems. [Above, stem detail photo from Broken Arrow Nursery.]
Margaret: Yes. And it starts out blue, and then it gets sort of fiery-colored later in the season. It’s also a lacecap style. That was one that they really liked a lot. Have you ever grown that? I haven’t grown it.
Ken: I’m growing it now. It has one flower.
Margaret: Oh, O.K.
Ken: Just got it.
Margaret: All right, so you just got it? O.K. Well, so that’s another one. Any others to recommend before we move right along?
Ken: Well, you’ve mentioned some of my favorite plants. I mean, the oakleaf hydrangeas, I love them. [Above, oakleaf hydrangea and hosta and Ken’s garden.]
Margaret: Oh, yes. Yes.
Ken: And they’re originally from the South; from Georgia, but they are very hardy, and there are people who are testing new selections that they want to grow up into Canada. So they’re going to be even hardier.
Ken: But they’re beautiful and reliable. I do know that they’re flood-intolerant. I discovered that.
Margaret: Yes, well, you with your floods. [Laughter.] Generally speaking, plants do not like floods.
Ken: But they’re so easy to grow, except they’re flood-intolerant.
- More: An interview with plant explorer and breeder Dan Hinkley on best hydrangeas of now and the future
why is a bird tapping on window glass?
Margaret: So we had a question, also, from Anita, about birds tapping on window glass.
Margaret: And this was a funny one. This one, I’ve heard before, and it’s one I’ve experienced at home, too. She says, “I have a Brown bird with a red breast.” It turned out to be a robin; she saw at a second time and wrote back to me. But she saw it, really, in a flash and then … You know. She continued, “…that’s tapping on my windows. I installed a high-frequency sound box outside,” you know, like one of those things that deter rodents and things like that. Didn’t help. And she knocked back on the glass from inside, as in, “Go away, go away. Stop banging.”
Nope, uh-uh, he keeps knocking. So she was like, “What’s going on?”
And this is one of those things that’s kind of fun. Of course what’s happening is he is seeing his reflection [laughter] thinking there’s another male in the territory and it’s his territory. Right?
Ken: I usually hear about this with rear-view mirrors on cars. And cardinals, actually.
Margaret: Yes. They’re one of the birds that is inclined toward this behavior. Absolutely. But I thought it was funny. And so what have you ever had to deal with it? I mean, I guess the thing is you need to put some fabric or paper or something on the outside of the window. I mean, putting something on the inside won’t necessarily get rid of the glare. You have to kind of go out and check, because the idea is to get rid of the reflection.
Ken: And if you have screens on the outside of your windows, that kind of takes care of it, too.
Margaret: Yes, yes. Yes.
Ken: I have not had that problem. I used to have a problem when the windows didn’t have divided lights. You know, with mullions or muntins.
Margaret: Sure, sure.
Ken: I would have accidents, and that was always so sad and depressing. Sometimes … Well, once, a bird crashed into the window. But now I have divided lights and it hasn’t happened since. So you don’t have to put those stickers on your windows if you have some kind of division in the glass.
Ken: But that’s a totally different thing. I have never had that happen, and I’m not sure what she should do. Wait until the bird gets old?
Margaret: [Laughter.] No, just you got to get rid of the reflection. So that there’s not that … Yes. I mean if it’s a car, you can change where you park the car and that’ll change the glare, the glint, and maybe they’ll stop looking at them. [More on this subject from Massachusetts Audubon.]
Ken: You could probably get booties or rear-view mirror cozies. And when you park … A lot of cars now have folding rear view mirrors, too. You could just fold them in.
Margaret: Yes, so I’d say at least temporarily, some kind of barrier. Like you said, the screen would do it, but taping up some paper, hanging a sheet, whatever, on the outside of the window. Get rid of the glare.
Ken: You know, there’s a get-rich-slow scheme.
Margaret: Oh, yes? Another one of yours?
Ken: Yes, rear view mirror socks.
junipers with brown inner needles
Margaret: Oh my. So Jo in central Missouri has a juniper question. She says, “I read with interest … ” She read a post on my website, which is very popular, especially in late summer onward, about inner needles of conifers turning brown. It gets a lot of search traffic, people searching for that.
And so she said, “I read with interest this story about foliage browning inside the shrub.” And she sent me some pictures [above, Jo’s photos of the shrub and a detail when she loves asdie the outer needles and looks inside], and she has some ‘Blue Star’ junipers, and says that some of the needles on the insides of the twigs were turning brown, but it was quite early, she thought, for this to be happening. She took pictures of the plant back to the garden center where she bought it and they said, “No, this is normal.”
And I looked at the pictures. The plants looked good, and apparently, they looked good unless you poke around inside. But junipers can suffer … I mean, you do see it; you drive by an area where they’ve used juniper as ground cover, for instance. And sometimes you’ll see enormous amounts of brown and so forth. Right?
Ken: Right. That’s kind of a different thing. That’s what you’re saying.
Ken: The brown on the inside, that’s just physiological. That’s the way it … Well, the plant is shading itself. And the new growth is on the outside. And as the plant gets larger and taller, it’s going to lose those needles in the inside. [Above, a white pine at Margaret’s exhibiting normal inner needle fading.]
Margaret: Right. So it unburdens itself of them because they can no longer conduct photosynthesis since no light’s reaching them, right?
Ken: Right, right.
Margaret: But the tricky thing with us all diagnosing our problems ourselves is that sometimes one thing can at first look like another thing, right? Yes, that may be very simple in some cases to see what it is. It’s only on the inner twigs, it’s not spreading, etc. But sometimes … You know, we’ve jumped to that conclusion and we haven’t fully examined.
So it’s good that she took it to the garden center. My feeling is if she’s not feeling comfortable after that visit to the garden center and doing some reading, I don’t think it’s bad to consult the cooperative extension plant-pathology lab, to contact your county cooperative extension or state cooperative extension and find out about getting a proper diagnosis. Because sometimes things are pathologies, not … You know what I mean?
Margaret: …not just the inner shedding of needles. So do you ever send things away for … Have you ever had anything tested?
Ken: No. [Laughter.]
Ken: I’ve had soil tests and I’ve had water tests over the years, and I do my own soil tests, but that’s really kind of different.
Ken: No, and especially now that you can look up almost anything online, you can find a lot.
Ken: But that’s a good idea. But, you know, cooperative extension and the land grant universities, they’re different in every state. There’s some states where they’re fantastic and they have all this money, and they have wonderful programs. And then some places I’ve been, there’s like 12 people and they’re hoping to get a guest speaker for $12. You know? It’s different everywhere.
Margaret: Right, it is different everywhere.
Ken: But of course it’s worth a try, of course
Margaret: Right. But there are various diseases of junipers and there is at least one that can also start on the inside.
Ken: Oh, really?
Margaret: From the tip. When it’s coming from the tip going inward, you know you’re in trouble. Right? So that’s like … You want to intervene right away, you want to get a proper diagnosis. And if you have other plants that it can be transmitted to, and so forth, like a giant juniper ground-cover area, that’s a problem. [A good diagnostic page for telling juniper issues apart based on the symptoms, from University of Minnesota Extension.]
But, yes. So I just don’t think that it’s a bad idea to try and ask for a diagnosis at the lab. I mean, a lot of extensions are staffed by Master Gardeners. I just talked to a Master Gardener the other day who actually volunteers at her county extension a certain afternoon a week, as do other people in the Master Gardener program. And she got a really tough question that she was telling me about, and she had no idea when the question first came in, what the answer was. But she did the research because she … You know, they have a tremendous database and library and lots of great materials there for her to use, so she sat and she did the research and she was able to get back to the homeowner. So I do think even in the counties that don’t have tremendous funding, is worth a try to-
Ken: And sometimes you talk to someone and if that person doesn’t know, they may know someone who will know.
Ken: Someone in the group often specializes in that.
Margaret: Right, right.
Ken: I think we talked earlier … I mean, a couple of … a month ago, or something, about juniper browning on one side from winter sun and wind.
Ken: And a bad winter. [More on winter burn of conifers from University of Wisconsin Extension.]
Margaret: Yes, also that. Yes, so where does it start? What’s the progression, if there is progression? Is it limited to one area of the plant? Are there any other … I mean, one of the things I asked her right away was it unusually wet? Because the ‘Blue Star’ juniper isn’t going to want to be in a pool of water. You know? Isn’t going to stand in wet feet, either.
Margaret: Things like that. Has anything changed? So, was there a dramatic weather event, or whatever? But, but yes, I do think that a lot of times, we want to find that instant Google search answer. Do you know what I mean?
Ken: Oh, of course.
Margaret: Without it being an authoritative site. And I feel like we need to go back to trusting, to asking for the help, whether online or using the phone number or the email service, or the Master Gardener answer lines and so forth. We need to go back to the source, to some more credible places that have a scientific orientation, that really have the resources to help us; as opposed to just, “Oh look. Wikipedia said to do this.” [Laughter.] You know? And then it’s like … And nothing against Wikipedia. I’m just saying it’s only as good as the people who put the information in there.
Margaret: And I’d rather get the plant pathology lab, in my case, at Cornell University … Do you know what I mean? [Read Cornell’s “Test Don’t Guess” fact sheet.]
Ken: As opposed to the box store.
Margaret: Yes, exactly. Exactly. So, O.K. I’m sorry, I’m just ranting now. [Laughter.]
Margaret: I’m ranting.
Ken: Well, isn’t that why we’re here?
Margaret: We’re here to rant. Exactly.
Margaret: Patricia had a question about Oxalis, the weed. Wood sorrel. Do you have that? [Above, photo from Wikimedia Commons.]
Ken: Doesn’t everybody? [Laughter.]
Margaret: Yes, I think so.
Ken: Yes, I do.
Margaret: And it’s funny, a lot of people think it’s clover, right? It looks like “clover.”
Margaret: Right? Right. So her question is … She’s in Maine, by the way. “Perhaps wood sorrel should be called a noxious ground cover,” she says. “I have those clover-like leaves with small yellow flowers throughout my gardens. And this year, when the heat finally arrived, it’s really taken off.” Yes. She says, “I’ve tried pulling it out, only to find that I might not be getting the long tap root. And also, if I disturb the soil, it seems like I’m releasing more seeds from last year so I’m helping it spread.” And mulching, she says, “hasn’t really seemed to make a dent.” And she tried vinegar spray. I mean, I don’t have any good answer for this. Do you have a good … I mean, I think I spent an hour yesterday, one hour was just on Oxalis. [Laughter.]
Ken: Oh, you mean weeding?
Margaret: Yes. Yes, yes, yes, yes, yes.
Ken: Yes, that’s … I-
Margaret: Because it had rained. It had finally rained, so it was moist, and so I pulled them out by the roots. You know?
Ken: Right. And some years are worse than other years. And this year, because we’ve had so much rain, it’s almost 18 inches tall in some places.
Margaret: It’s hilarious, right? And I have two different species. I have the sort of more creeping one that’s reddish [Oxalis corniculata].
Ken: Oh, yes. Like the reddish one? [Photo above of creeping wood sorrel from Wikimedia Commons.]
Margaret: And that’s a different species from … I think the yellow, more upright one is O. stricta, I think. I’m going to forget the species of the other one. But yes, I have two different ones. Not only do I have it, I have two. [Laughter.]
Ken: Well, in general, I’m not a fan of foraging because you have to really know what you’re eating.
Ken: You may think this is a leap, but wood sorrel is delicious.
Margaret: You’re kidding.
Ken: No. You never tasted it?
Margaret: Well, I’ve tasted sorrel, the plant sorrel [Rumex acetosa, not an Oxalis].
Ken: Well, it tastes like sorrel.
Margaret: Oh, it-
Ken: It’s lemony and-
Margaret: I see.
Ken: A little fruity. And lemony.
Margaret: I see.
Ken: And it’s very good snipping off a couple of leaves in a salad.
Ken: Or garnishing a soup. Trust me. You could try a leaf and you’ll be surprised how good it is.
Margaret: O.K., I’ll try a leaf. I’ll try a leaf.
Ken: Which doesn’t help at all with weeding, because you can only eat like three leaves.
Margaret: No, no, no.
Ken: But at least it’s some kind of revenge.
taking care in the heat and humidity
Margaret: Yes. So what’s going on over there? Any other … Besides your dodder issue, what else is going on over there?
Ken: Well we’ve had more rain than ever, actually.
Ken: And the hottest June on record.
Ken: And you’ll probably remember way back in July, there were three days … Well, here, it was over 90 for three days.
Ken: And I was out there, again, not thinking. And not for very long, and I couldn’t figure out what was wrong with me. I thought maybe I’d taken the wrong medication or something. I had the weirdest symptoms. And then I remembered that night that, over 30 years ago, I had had a very similar thing happen where I had heat stress.
Ken: And now it’s a couple of days later. Well, it’s almost a week later, and I was just out this afternoon and I started to feel it again, because it sort of lingers.
Ken: And it’s like my head is almost throbbing kind of quickly and I take little short breaths and I don’t exactly get out of breath, but it’s the weirdest thing. But I think it’s just too much heat. I have to be more careful, and drink, drink, drink.
Margaret: And I think it’s really a good thing for us all to remember because this outdoor work, especially when we get into the high heat of peak summer, and in our region it’s humid as well as in many regions, it’s humid, as well as hot. I mean, this is hard on the body. It’s not easy. You know? And so the early morning hours when there is some fresh air, or the evening hours are probably better than the mid-day hours are. It’s tough stuff. So yes. And as you’re saying, hydrate, hydrate, hydrate. Yes.
Ken: And you know I have a lot of shade, and you’d think that would be good enough. But-
Margaret: Not when it was as hot as it was.
Ken: No, and people who want to grow vegetables—in the morning, in the evening, cut flowers, vegetables. Just don’t be out there in the afternoon.
Margaret: In the middle of the day, yes. Well, I guess we will entertain some new questions in a couple more weeks. And I know, also, as we said at the beginning of the program, we’re going to be meeting up in mid-September at the New York State Writers Institute Book Festival and lots more good news to come. Right, Ken? You might be having a new book coming before too long? So we’ll talk about that someday soon.
Ken: [Laughter.] Yes, we will.
Margaret: O.K. All right, so I’ll talk to you soon.
Ken: Thanks, Margaret.
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MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its 10th year in March 2019. In 2016, the show won three silver medals for excellence from the Garden Writers Association. It’s produced at Robin Hood Radio, the smallest NPR station in the nation. Listen locally in the Hudson Valley (NY)-Berkshires (MA)-Litchfield Hills (CT) Mondays at 8:30 AM Eastern, rerun at 8:30 Saturdays. Or play the August 19, 2019 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes/Apple Podcasts or Spotify or Stitcher (and browse my archive of podcasts here).