Ep 137. Overwintering Potted Perennials
Sat, Dec 02, 2023 3:00PM • 11:42
SUMMARY KEYWORDS
pots, plants, garden, freezing, perennials, overwinter, gardens, foliage, root, garage, pink, remain, ghosts, annuals, dilemmas, spring, winter, soil, grow, mary stone, garden, nature, inspiration
SPEAKERS
Mary Stone
Mary Stone 00:00
Hello fellow lovers of all things green. I'm Mary Stone and welcome to Garden Dilemmas, Delights and Discoveries. It's not only about gardens, it's about nature's inspirations, about grasping the glories of the world around us, gathering what we learned from mother nature, and carrying these lessons into our garden of life. So let's jump in in the spirit of learning from each other. We have lots to talk about.
Mary Stone 00:26
Hello there, it's Mary Stone on the screen porch here in New Jersey, it was only 22 degrees today and I was still doing fall cleanups for clients here in this late November time of year. It seems much colder to me, because, you know, I just came back from Virginia and Tennessee, so I got a little soft, maybe. Or maybe it's because I didn't dress warmly enough, bringing in the potted gardens filled with perennials. I hope their little tootsies haven't frozen, poor things. I should have brought them in before we left, bringing me to today's story about Overwintering Potted Gardens.
Mary Stone 01:05
But before that, I'd like to thank those who reached back after last week's chat about Giving Thanks for the Gifts of Nature, including deep freezes, which helps those of us that suffer from seasonal allergies. And the snow squalls that passed by yesterday is hopefully a taste of things to come. You know how much I love snow.
Mary Stone 01:25
So the story we'll visit today is when I used to have garden ghosts, which I don't often have any more. I hope I piqued your interest, and it starts like this.
Mary Stone 01:36
Hello fellow listeners and readers. With the recent below freezing temperatures my garden ghost routine of covering pots with sheets to keep them from freezing has begun. This was in late October by the way. Admittedly, it's silly as acceptance that the growing season is over will eventually set in. About when I grow weary of the ritual, or when the ghosts are more in view than the plants left in hiding.
Mary Stone 02:03
Potted gardens have become more than annuals. Many include perennials and small shrubs to kick them up a notch. Mary hugger tree feels guilty for letting plants that can return each year die in their pots. But I suppose letting them go is okay. Are annuals or perennials in warmer zones. So, what are we supposed to do, save the world? Sound convincing? I'm not buying it. And neither is Ron from Bangor, Pennsylvania, who asked how to overwinter garden pots. I bet Ron has garden ghosts too.
Mary Stone 02:38
Concrete glazed or terracotta pots with or without plants will crack if left out in the winter. Except for those fancy shmancy ones. I should add costly ones made to withstand Old Man Winter. Generally, fiberglass, polyethylene and structural foam pots can remain outside. While these pots are insulating, even plants suitable in our zone will suffer from the freezing and thawing of roots if unprotected.
Mary Stone 03:06
Some say that two zones hardier - zone three plants in zone five, for instance - may overwinter just fine. Still, plants can quickly die if water accumulates and freezes. So be sure the insulated pots drain well.
Mary Stone 03:22
You can plant the pots themselves if freeze tolerant in a holding spot dug in the soil to the top of the pot until the following spring. Or gather them against the north or east side of your home and cover them with a foot of shredded leaves or straw.
Mary Stone 03:38
Containers moved into an unheated building such as a garage or shed where temperatures remain slightly above freezing are ideal, especially for the breakable terracotta. There's a picture of my dear Ellie, my golden retriever that preceded Jolee looking over the pots overwintering in the garage. I'll put a link in the show notes to the column.
Mary Stone 03:59
Regardless of your technique, roots must never dry out. So, keep plants moist until the first hard freeze and check the soil whenever the temperatures rise above 40 degrees. Lastly, allowing your plants to go dormant is essential before putting them to rest. So maybe my garden ghosts aren't so silly after all. Again, this was in late October. Garden Dilemmas, AskMaryStone.com.
Mary Stone 04:27
I have to say each year the pots come into the garage over winter, causing a bit of stress for Curt, as it impedes access between the garage bays. And so, he likely wishes the story of Filling Naked Pots Late in the Season. Never came to be. And I think we have some time to share that story.
Mary Stone 04:47
Six summers ago, the pots between the garage doors remained vacant since the Yellow Jacket dilemma due to the proximity of the nest and the risk of anaphylactic shock to loved ones. A non-organic approach was sadly called for. If the Yellow Jacket nest was not in the tenuous spot, I'd have let it be, as they only nest in one place once and will not return the next year.
Mary Stone 05:12
There's a more earth friendly spray that contains pyrethrin extracted from the pyrethrum daisy that will not harm established plants, but you must apply it every 48 hours due to its efficacy timeframe. The longer lasting artificial chemicals, called pyrethroids, works for up to three weeks. By the way, you won't see the word pyrethroid on the labels which is confusing or maybe it's intentional, but the pyrethroid ingredients listed often end in thrin. While the chemicals will kill the wasp nests quickly, they also harm plants. And of course, there's a concern for our environment. Many countries have banned the pyrethroid use as pesticides.
Mary Stone 05:55
Because of the chemicals, I dumped the soil and nest remains far from the compost and garden and filled the pots with new soil. I missed out on the annuals I used to plant but perennials are a perfect solution for container gardens that return their favor year to year, providing a happy ending to naked late season pots. I had fun perusing a favorite wholesale nursery. I barely am able to shop for my gardens during peak season. I found the ‘Mini Penny’ mophead hydrangea I was looking for to serve as the anchor place in the collection of pots. However, she was blooming pink rather than blue due to the alkaline soil versus acidic it was rooted in. And as my dear sister can attest, I'm not a fan of pink. You see my sister's seniority offered her the right to choose the color of her bedroom, which was Pink Panther Pink, not the real name but certainly a descriptive that haunted our walls growing up. It seems to me the warm and earthy green I campaigned for would have been more soothing, not leaving a residual dislike. Who doesn't like green. It's the primary color of our dear Earth after all.
Mary Stone 07:07
When the three- to four-foot-tall bloomer is planted in my acidic soil, she'll become a beautiful baby blue. Or I could add Holly Tone or Pro Holly or lime pellets to the potting mix. But I couldn't fathom waiting for the shift. Some childhood aversions last forever. Instead, I chose a perennial option as the anchor plant grabbing three brunette snake root, Actaea ramosa, aka Cimicifuga simplex, with dark purple foliage. They'll grow four feet tall with bottlebrush white flowers with a tinge of pink in early fall. Yes, this a hint of pink is okay. One must remain flexible.
Mary Stone 07:46
To complement the snake root, I stumbled upon Sugar and Spice foam flour, Tiarella x ‘Sugar & Spice,’ with her bright green deeply lobed leaves and dark burgundy centers. She too forms spikes of pinkish white flowers in spring above her foot tall foliage.
Mary Stone 08:04
I couldn't help but try the shiny heart shaped leaves of Beesia, Beesia deltophylla, from the Dan Hinkley collection. Dan Hinkley is a legendary American plantsman, known for collecting and propagating unusual plants. And while Beesia is best in zone six to eight which pushes the envelope here. When it's time to transplant from the potted gardens to the garden beds, I'll opt for a microclimate protected by winter winds for this spreading semi green woodland plant that grows 18 to 24 inches tall.
Mary Stone 08:37
Then ‘Alexander’s Great’ Siberian bugloss, Brunnera macrophylla, called my name. He's a larger version of the more well known Brunnera ‘Jack Frost’ with silvery dark vaned heart shaped leaves and sky blue clusters of flowers that come spring above the 18 inch tall foliage.
Mary Stone 08:56
I planned to divide the Hakonechloa macra ‘Aureola,’ Japanese forest grass, spreading nicely in the rock garden to add a wispy edge along the garden pots. But instead, I opted to adopt pots of 'All Gold', a variety with bright golden yellow foliage. And it's so fun because they grew in like the bangs on my much-adored Mother Earth face pot gifted to me by dear clients.
Mary Stone 09:21
All these selections will contrast nicely with the big leafed blue Hosta donated by a client. Plus, the new plants have good deer resistance and will spread over time when I move them into the woodland garden in the fall. A happy ending to my naked garden pots begging for attention. Yes, indeed. But the punchline is that I've never moved them into my gardens. Well, I think actually a few of them I have, but by and large I've been moving the pots in and out of the garage year after year for the last six years. So, talk about a happy ending that's recurring, year after year. Well, maybe not for Curt because it does take up space in the garage. But it's always such a delight to see the reemergence of the plants in those pots in the garage each early spring. And I look forward to bringing them out each year.
Mary Stone 10:12
But I do have to admit the ‘Brunette’ Snakeroot, (the Cimicifuga) with a dark purple foliage that is the hair of my Mother Earth pot has not bloomed the last few years. So, it's probably root bound, and time to free them from the pot and place them in my woodland garden, which would be a happy new beginning to look forward to come spring. But for now, if you don't mind, let's enjoy the winter rest from gardening. As we dream about the new season of growth ahead. It is something to look forward to indeed.
Mary Stone 10:45
So thanks for coming by. I always enjoy our time together and I hope you have as well and if so, please share the podcast with a friend or two. It's such a joy to watch our community grow. And the more of us that learn and grow together can make a big difference in the world around us and with each other. Thanks again. See you next time on the screen porch. Hopefully it'll be a little warmer. But Snow please bring on the snow.
Mary Stone 11:12
You can follow Garden Dilemmas on Facebook or online at Garden Dilemmas.com and on Instagram and hashtag Mary Elaine Stone. Garden Dilemmas, Delights and Discoveries is produced by Alex Bartling. Thanks for coming by. I look forward to chatting again from my screen porch. And always remember to embrace the unexpected in this garden of life. Have a great day.