IT’S BULB-PLANTING SEASON–or more accurately, I should say it’s geophyte-planting season, because not all the dormant storage organs sold in bulb catalogs are actually bulbs, technically. But all are clever stockpiles of water and carbohydrates stashed by these sturdy plants for when there’s not a rainy day.
Whether you get technical or go generic with your terminology, it’s time to tuck tubers and corms and tuberous roots and rhizomes and yes, even some true bulbs into the soil for years of enjoyment. But which ones, and how?
With help from horticulturist Jonathan Wright of Chanticleer Garden, who joined me on my public radio show and podcast, we’ll learn some less-than-expected uses of bulbs, like massed in lawns [photo below, at Chanticleer], and layered in containers. Plus: tips such as which bulbs are more animal-proof than others, or how to get your tulips to last many years.
Jonathan has his BS in horticulture from Temple University, and a diploma from the famed Longwood Professional Gardener Program at Longwood Gardens in Kennett Square, Pennsylvania. Since 2004, he has been a horticulturist at Chanticleer Garden, a public space in Wayne, Pennsylvania, known for its dynamic plantings. He is contributor to the new book, “The Art of Gardening” (enter to win a copy at the bottom of the page). Most important of all: Jonathan knows his way around that group of plants we call bulbs.
Read along as you listen to the Sept. 28, 2015 edition of my public-radio show and podcast using the player below. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).
my q&a on bulb planting, with jonathan wright
Q. You’ve been at Chanticleer since 2004, as I said—but gardening far longer than that, and in the same general vicinity, too. Was your first horticulture job was at age 13?
A. My sister is still making fun of me for an article called “Early Bloomer” talking about the fact that I have been gardening since I was 13. I started at the local garden center, potting up plants and helping customers with purchases. I had been a customer and would be answering questions for my Mom, and would help other customers, so they sort of had to give me a job.
Q. [Laughter.] And where was “local” at the time?
A. It’s a great little local family-run nursery in Unionville, called RP Nurseries, just around the corner from Longwood. I was very fortunate to grow up out that way.
Q. At Chanticleer, which areas are you responsible for–I know there are seven horticulturists on the team, and you each have specialties. Each of you contributed to the new book about Chanticleer called “The Art of Gardening,” too – congratulations on that.
A. Thank you. My area is around the Chanticleer House—what we call the main house, and the terraces that surround it. I am responsible for all the seasonal displays, the containers. For those who have been to the garden, there is a big, beautiful, rolling hill that rolls down away from the house. I take care of the Serpentine Garden, the area as you look down the hill off to the side, and sort of everything in between that, down the hill and up to the plantings around the house. And that includes a big new elevated walkway that we have done—a big mixed grasses and herbaceous plant palette, which is a lot of fun.
Q. So you have your hands full.
A. But it’s a good kind of full; it’s a gardening kind of full. You’re never done, so that’s good.
Q. I love the word geophyte, as I say in the introduction, and in it there really is testament to just how tough and rewarding bulbs and bulb-like plants are–and how easy, if you know how to make them happy. But sometimes they confound people anyway.
For example: People think tulips are like an annual–and they can be used that way, where you plant them an then basically throw them away after bloom as if they aren’t going to come back. But that’s not the case, is it, if you select the right ones and plant them the right way?
A. It’s not the case; they’re not just annuals. Certainly many people grow them that way, and there are a few that we grow that way, too. Depending where you are in the country—for instance, in the Pacific Northwest they’re longer-lived perennials—but typically people on the East Coast and Northeast think of them as annuals. But if you choose more perennial types—a lot of the more species perennial types like Tulipa tarda and batalinii, the small species ones…
Q. ….the non-hybrids.
Q. The non-hybrid ones [left, T. clusiana]—keen gardeners have known for years that they are more dependable. I think people think of them as rock-garden plants because they’re smaller, more diminutive. One of our gardeners, Joe Henderson, uses them beautifully on a steep hillside where he’s used gravel as a mulch. He’s tucked them in with other bulbs that are obviously hardy, like grape hyacinth—Muscari armeniacum. People love Muscari because it’s easy and dependable, but tucking in a few of these tulips with it—the color combination is gorgeous, and they’re much more reliably hardy than some of the big hybrids. [Photo, top of page.]
Q. But some of the big hybrids can be pushed a little, yes?
A. We’ve been noticing that the Darwin hybrids, as I’d heard years ago, can be more reliably perennial. Then I learned a trick from our friend Brent Heath at Brent and Becky’s Bulbs, who told me he found that if you planted them extra-deep, it sort of insulated the bulbs from summer rain fluctuation, when it can be dry or it can be wet—it depends.
If they’re planted really deep—not just 6 or 8 inches but 10 or 12 inches—that really insulated the bulbs from that moisture fluctuation. It also puts them just a little bit more out of reach of the moles and voles that go around at the top of the soil that would get them.
Q. Yes, I know of those creatures [laughter].
I didn’t know it was Brent Heath who told you that, but I think I must have picked up the tip there, too. I don’t have tulips in the garden, but I like to have them for cutting, so I pick my favorite colors and I get a few dozen of this and a few dozen of that, so I could pick some bouquets. [Below, cutting tulips in a raised bed at Margaret’s.]
I think what you said about being deep enough to be away from moisture fluctuation—that gets back to the geophyte thing. These are plants that typically have a long period each year where they are fully dormant and not only don’t need the resource of water, but they don’t want it.
A. They don’t want to be getting that deluge of water from that errant summer thunderstorm. So putting them deep really helps. And you’re absolutely right when you said there is so much of the year when they are completely dormant and don’t need anything.
We gardeners see a hole in the garden and want to go fill it with an annual or a pot, and if they’re only 6 inches deep you’re very likely to slice through that beautiful bulb or corm or tuber with your spade or your trowel. So putting them deeper, you’re less likely to nick them.
Q. The margin of safety.
Let’s go even smaller for a moment, to the idea of bulbs in pots. You are quite a daring container-garden designer, I know, Jonathan—including with bulbs. So how does that really work? And what Zone are you in, I should ask?
A. We’re a solid Zone 6; when they started with the changes they said we were a warm Zone 6, but then the last two winters we were a cold Zone 6. So Southeastern Pennsylvania I’d put in a solid Zone 6
So bulbs in pots can be tricky. Some people say just pot them up and leave them outside, but then the pots can get damaged or the bulbs can rot. So it’s actually not difficult—but you just have to find a place that’s somewhat protected.
For me, doing a lot of bulbs in pots started as my obsession of wanting to try everything. So as a home gardener, at the end of the season when they were on sale at the garden center, they’d have a bag of unusual Narcissus or hyacinth or tulip. I’d get bags here and there, and I didn’t have a greenhouse or anywhere to force them, so I’d pot them up and put them along the back of the garage under the hedge. They were out of the sun, out of the wind, and I’d cut up the Christmas tree at the end of the season and cover them with branches.
Then you have to remember if you have a snowy winter to to get out there when the snow melts and uncover them, or if you have a mild winter, earlier—so you don’t crush the foliage that’s starting to emerge. That worked really well.
Q. When you say pots—these are pots that themselves are weatherproof? Not a terra cotta pot?
A. Yes, I’d recycle plastic pots or nursery pots. With a little bit more protection you can get away with using terra cotta, like in a coldframe or an unheated garage that is a little more stable. In an unheated garage, I’ve potted them up in simple terra cottas and put them against the inside wall of the house, and that works almost as a coldframe.
You have to watch the moisture if it’s inside, though; you don’t want them to dry out.
Q. Yes, you said a few times that you don’t want them to dry out, and also you mentioned that they can rot. I had some Narcissus left over from big backs I naturalized last fall—and I guess I got tired of digging the holes [laughter]. I had a few-dozen left and I thought, “Oh, I’ll put them in these tubs,” almost whiskey-barrel sized ones.
But of course Margaret didn’t think about the fact that those particular tubs don’t really drain as well as bulbs need to. So they had the freeze and thaw and freeze and thaw, and they ended up with ice on top and almost a waterlogged situation, or “wet feet.” Not a good thing for a bulb, right?
A. Geophytes in general don’t want to sit in water; there are a few exceptions of things that grown in boggy soil. We have to be very careful with that.
If they are leftover bulbs and you want to experiment, covering those plants with branches, such as pine boughs, could help shed a lot of that water. We have to then just remember to take it off before they start growing in the spring.
A. [Laughter.] It sounds so funny, but that may be another thing I picked up from Brent and Becky Heath. I think they talked about it. It works really well. One of my colleagues, Dan Benarcik, has done it really well, where you take a large container that’s frost-proof or that you’re putting into a sheltered spot for winter.
You put a little compost on the bottom or good garden soil, good potting medium. And then you start with your biggest bulbs on the bottom, and do a layer of those, and top it off with a little compost. So as you work up, the soil is getting shallower and shallower and you use smaller bulbs, so it might be giant Narcissus on the bottom, a large tulip next, then followed by a Camassia or hyacinth, and the whole thing could be topped with Crocus or Muscari. At each layer in the pot, you’re got this sort of soil-bulbs, soil-bulbs.
The great thing is that you’ve got this progression of bloom, and there is always something happening in the container from early spring on.
Q. And that’s a great way—layering, which is what that essentially is—layering is a great way to use bulbs in the garden, too. You can use just one kind in mass, but you can also do this mixture in your garden beds, at different depths.
A. Definitely. All the bulbs want a different depth, and maybe as a lazy-gardener’s approach since you’re digging that hole anyway, you dig one hole and fill it three times. We did that with our wildflower lawn. We had an area of lawn that we were turning over from traditionally mown turf and we were going to replant it with a no-mow fescue. We thought, “How great would it be if we had bulbs coming up through it in the spring?”
We actually dug holes in it with a bulb drill, and we put a large Narcissus in the bottom, backfilled a little, then put a large tulip in—a Darwin hybrid. Then on top of that with a little more soil and then a smaller narcissus bulb so that we ended up with two different daffodils and a tulip in each hole, and they all bloom at different times, but occupy the same space.
Q. You said “bulb drill,” and is that like an auger—on the end of a drill?
A. Exactly. They’re particularly good if you’re naturalizing. Ours is essentially like a chainsaw engine but comes with an auger bit, made for professional horticulturists and landscapers. I know they sell heavy-duty bits you can use with your cordless drill or even your corded drill. It really does save a lot of effort, especially if you’re going between existing plants and don’t want to big a big, wide hole. This is pretty precise and makes quick work of it.
Q. Now about bulbs in lawns—you’re used things like species Narcissus, and you just mentioned a layered approach including tulips. With the tulips, did you expect those to dwindle over time? You knew the Narcissus would keep on keeping on, or Camassia would for instance, but what about the tulips?
A. We chose ones that were Darwin hybrids that I thought were pretty reliable; ones that I’d known had come back if I’d left them in. And we did the extra-deep planting, which was another nice thing about the drill: I could put a tape-measure mark on the drill bit, and know that I’d gotten to a depth of 12 inches. That was really helpful.
So we planted them extra-deep. The mix of tulips we used included three or four different yellow cultivars; a beautiful purple one called ‘Negrita,’ which is lovely…
Q. Oh, that’s a great one; I think it’s the best of the dark ones.
A. Isn’t it great with that sort of Concord grape color. And then ‘Queen of the Night,’ really lovely, too, and darker, but is much later and a smaller head. So it was sort of a progression of yellows to purples and blacks.
I thought, we’ll plant them extra-deep and maybe we’ll get two seasons out of them.
A. They have been so prolific that I tiptoed through the lawn and I cut them because they almost look like bouquets—they multiplied.
Q. They overdid it?
A. They’re almost coming up like bouquets, yes. Part of me is thrilled that they’re so happy and proliferating, and part of me thinks I wanted it to look like a wildflower meadow and now it looks like bouquets.
Q. It’s the tussy-mussy lawn! [Laughter.]
A. It has that sort of little tufted effect. And then you can cut them for the house.
Q. I told you about my “crocus lawn” project a number of years ago: 4,000 planted, 4 flowered. As for animal-proof bulbs, we’ve mentioned Narcissus a couple of times—seems like nobody in general eats daffodils. Alliums (the ornamental onions), and Fritillaria—are there others you have noticed don’t have interest for animals?
A. Those are the top three. And you burst my bubble when we spoke recently and you told me that the crocus that you tried were the Tommie crocus, Crocus tommasinianus.
Q. Well, yes, but I have fierce animals here; I swear I live in “Animal Planet.” Don’t worry; maybe it won’t happen to you. [Above, beheaded Crocus tommasinianus at Margaret’s garden.]
A. We’ve been really fortunate so far here; they haven’t eaten our Tommie crocus, and we have them in big numbers in two parts of the garden—one in lawn [above], and one in a perennial border. They’ve naturalized and become carpet in both areas, and the rodents haven’t seemed to bother them at all.
Other gardens in our area have had no problem. Winterthur and Longwood have beautiful stands of them.
Q. I may try again.
Q. My favorite. [Above, winter aconite under a magnolia in Margaret’s garden.]
A. The rodents haven’t seemed to bother it.
Q. That’s the first bulb for me in my garden; as soon as the snow melts, it’s up within two days or so.
A. It’s right with the snowdrops for us. And snowdrops have been very rodent-proof for us as well; I haven’t noticed any problem with the Galanthus.
Q. Do you have some favorite bulbs that you think everyone should try? I love Nectaroscordum [left], the Allium relative, for example.
A. You’ve already mentioned the Allium as being rodent-proof, but it’s probably my Number 1. It blooms later—many of the alliums fill that gap between late spring and early summer. There is the cheapest, most readily available Allium ‘Purple Sensation,’ and they are prolific for us. They just come bask; they look like little purple fireworks bouncing through the borders.
And they don’t break the bank. Some of the really big ones like ‘Globemaster,’ the Allium giganteum like ‘Lucy Ball’—there are all these great cultivars of ones with massive heads. They’re really stunning, but they can be really pricey.
What I usually do: I buy a bunch of the cheap ones, and I buy a few of the expensive ones each year, and just keep adding to it. I think they’re really good fun. They’re the ones that even my sisters, who aren’t really into flowers or plants much—when they see pictures of things like that they really respond.
A. I’m also a big fan of fritillaries. You mentioned them as also being rodent-proof. A sort of lesser-used one is the checkered fritillary [F. meleagris], which I think is so beautiful, and it can tolerate a little bit of moist soil if that’s an issue for people.
Q. When do you transplant bulbs if you need to? “In the green?” (meaning when they have leaves on them), or…
A. Experts disagree on this. I tend to be very successful with moving many bulbs in “in the green.” Mostly because you can see them and know you’re not damaging the bulb itself. The other answer for gardeners is ”when you have the time.” We were joking about that yesterday: When you have time is the right time to do it.
Q. Do you bother with “bulb food?” either at planting time or any other time?
A. Generally, no.
Q. Me, neither.
A. But there are a few bulbs that I do put some bulb food on, if I want something to be really, really showy. I bought a couple of stunning Fritillaria raddeana last year from Brent and Becky, and it was one I hadn’t grown—sort of a chartreuse-apple green. A smaller version of the crown imperial. I don’t know if it made a difference, but it made me feel better.
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MY WEEKLY public-radio show, rated a “top-5 garden podcast” by “The Guardian” newspaper in the UK, began its seventh year in March 2016. 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 Sept. 28, 2015 show using the player near the top of this transcript. You can subscribe to all future editions on iTunes or Stitcher (and browse my archive of podcasts here).
enter to win the chanticleer book
I’LL BUY A COPY of “The Art of Gardening: Design Inspiration and Innovative Planting Techniques from Chanticleer,” for a lucky reader. All you have to do to enter: Comment in the box at the very bottom of the page, after the last reader comment, answering this question:
Is there a bulb you rely on most, and another you keep meaning to try, and why?
I so look forward to the Eranthis each March or April (and so do the earliest-awakening bees), and am a nut for Nectaroscordum, as Jonathan concurs.
No answer, or feeling shy? Just say something like, “Count me in,” and I will, but an answer is better. I’ll select a random winner after entries close at midnight on Sunday, October 2. Good luck to all.
(Photo credits: Rob Cardillo, from “The Art of Gardening” from Timber Press, except Eranthis, tulips and beheaded Crocus from A Way to Garden and bulbs in pots from Jonathan Wright.)