Harvest Moon Newsletter

Hi Plant People,

Happy Harvest Moon!

Apologies for radio silence. Life has been wild. I had an incredible adventure in England, lecturing and touring gardens. But this is my favorite moon of the year and I’ve got a lot to share. It’s a Best of Summer Newsletter! The rundown:

I am happy to announce that I’m now a Program Associate with the Harvard Divinity School. I’ll be working with the Thinking with Plants and Fungi Initiative. I lectured for them this summer on the role of community, justice, and storytelling in ecological horticulture. I was so happy to be able to share this and you can watch it here.

My TED talk has nearly a million views!!! I am both entirely blown away that so many people have watched it, as well as like, really? 25k more people? Can we not make that happen?

And I’m worried this just sounds like boasting, I really don’t mean it to. There’s just a lot of awesome stuff happening and you’re reading the “about me” section so: Brook Klausing and I were awarded the Perennial Plant Association Award of Excellence for our Brooklyn Museum garden!!!

If you’ve missed me, you can hear me on the Wild Story Podcast, see Laura Fenton’s guide to lazy gardening, or read an interview with me in Horticulture Magazine by the amazing Scott Beuerlein.

After 3 years working on a 200 year old farm house, my family and I moved into the prettiest house I’ve ever seen. We finally have land to care for and wow, am I going to spend the rest of my life making it gorgeous. Once I get settled, I’m going to start designing again. If you have a public project you think I can help with, please let me know.

GARDEN NOTES

Fall is not for cutback. I know, you know. Wildlife need those seeds and also, seed heads make great winter interest. Fall is also not the time to rake out beds. Those leaves are critical habitat for animals, as well as one of the main ways that plants cultivate the soils they want to live in.

Leaving the leaves also benefits us. Leaves slow down water from extreme storm events and allow it to percolate into the soils. The leaf layer of an oak forest can hold all of the water of a 2” downpour. And a study in Maryland found that, by leaving leaves on landscapes, soils held on average 32% more carbon!

So what are we supposed to do in fall? PLANT of course. Aside from a few species, fall is really the best time for planting native plants. If you time it right and weather cooperates, roots get established over winter and watering the following summer can be minimal.

Fall is also my favorite time to divide plants. Rules of thumb encourage us to divide fall blooming plants in spring, but with rare exception, as long as I finish 6 weeks before frost, my plants appreciate the cooler temperatures of fall. While I appreciate that they need less water in summer, because I am actually a very lazy gardener.

Gardenista published a solid guide to dividing in the fall. And Fine Gardening has a helpful list of species with special requirements in their division guide. But perhaps my favorite info on plant divisions, comes from their very own root systems. Knowing how to read a root system can teach you more than any book. Noel Kingsbury wrote an excellent piece on learning plant behavior by looking at their roots.

RESOURCE SPOTLIGHT

• Brooklyn Bridge Park’s horticulture resource page is both quite useful and quite hard to find. It’s here. Enjoy. The weed guide is my fave.

• We all hope the trees we plant will live for a century or more, but the climate in 100 years is going to be very different from today’s. How to plan? The best resource is the USDA’s Climate Change Tree Atlas but a warning: it is not for the faint of heart. It’s complex and dense. Still, there’s info about trees species tailored for most US cities and states. Here’s New York. If you are a stat-savvy garden writer, mining this for climate adapted tree listicles would be a public service.

• This is the cutest video I’ve ever seen on the importance of organic soil management. It’s a 5 minute journey through the nitrogen cycle that will teach you more than many books have.

• Everyone loves trees. Flowers are the best. And grasses are hip. But what about shrubs? Where is the love? Kevin Philip Williams and Michael Guidi have published an elegant and somehow punkrock manifesto on shrub design. Shrouded in Light shares inspiration from natural shrublands throughout North America and is really just beautiful.

• Are you a member of Wild Ones? It’s a chapter-based ecological gardening group that provides support for those of us in the field, both newbees and oldbees. They have a library of free regional landscape designs and designer extraordinaire, Preston Montague, expounded on their usefulness in the New York Times.

IN THE NEWS

• Snags are officially having a moment. Every single fancy garden I visited in England, from Sissinghurst to Kew, had one prominently displayed. Dead and dying trees are one of the most biodiverse ecosystems we can encourage and the garden world is figuring out how to incorporate them into our managed landscapes. Margaret Roach profiled Basil Camu, an arborists who refuses to cut down trees all together. Sure, he makes them safer: if a tree is leaning, or branches may fall where someone might get hurt, he minimizes the tree, but pushes back on the idea that we should remove all traces of its existence. Why stump grind? Why cart away branches? Mr. Camu is like a tree hospice nurse, making sure they are safe as they travel to their final resting place in the soil.

• Gone are the days when we viewed cities as ecological wastelands. A new study out of Chicago found that small, urban patches of Milkweed, even in a pot on a roof, is a huge help to Monarch butterflies. Asclepias syriaca was most favored by monarchs, and older plantings were preferred to new ones. A diversity of nectar plants were also helpful. Paper here.

• And planting milkweed far from agricultural areas seems to be increasingly important, as the toxicity of those landscapes is harming butterflies in general, and Monarchs in particular. New data suggest that systemic insecticides like neonics account for 8% of all US butterfly declines, but a full 33% of Monarch declines. This is bonkers. We absolutely have to ban them.

• Super hip, west coast outfit Terremoto reimagined the landscape around a century old Frank Loyd Wright residence in LA and by god, they are good at their work. Look at this! It’s gorgeous! And cool and ecological, political and historic. Heart eyes galore.

• Gardeners like to plant. It’s what we do. But sometimes, it makes sense to NOT plant. Seed banks are local biodiversity reservoirs that many plants use to distribute themselves through time. In areas where seed banks might remain, under lawns and woodlands, allowing those plants to emerge makes more ecological sense than bringing in new species and genetics. This wonderful long-read in High Country News profiles restorations conducted by indigenous groups and the entire thing is worth studying carefully. It highlights the way non-native ecologists often want to “spray and plant” our way to restore individual species, while “some tribal scientists say that if traditional ways of caring for landscapes, through fire, harvests and seasonal flooding, return, plants will also return. So will pollinators, fish, birds, mammals and cultural connections to them, restoring a way of life, a long-term relationship between people and place.” Recognizing the leadership of indigenous groups and returning native land to its rightful caretakers are critical parts of biodiversity work. For gardeners, there can be “value to pausing and seeing how sites respond, letting the landscape talk to you and not try to force something.”

• Restrictive Homeowners Associations can be serious barriers to those replacing lawns with native plants. Strategies for getting around them are popping up all over but Illinois just made a law that HOA’s can’t ban native plants! They did it by nixing height restrictions on plants in yards. Hopefully this spreads.

• It can seem lame sometimes to promote biodiversity as a self-interest topic. Non-human organisms should be allowed to live their lives without being “useful” to people. But it’s also undeniable that we seriously harm ourselves when species decline, often in indirect ways. The loss of Ash trees in the US is believed to have caused 20k deaths from respiratory and cardiovascular incidents. Vulture decline in India killed a half million people from lack of sanitation. And white nose-syndrome in bats lead to more than a thousand infants dying from the effects of all the pesticides farmers were using to make up for missing bats. Protecting and supporting biodiversity is not just altruism. It is absolutely critical for humanity as well.

• Butterflies get a bad rep as pollinators. I can’t tell you how many ecologists I’ve heard describe them as “bad” at pollination because of their long, skinny legs. But just because bees are fuzzy and have pollen baskets, doesn’t mean that butterflies are less than. They’re just specialized. There are plants like Azaleas and Lilies who have hitched their reproductive wagons to butterfly wings, morphing their petals to provide a resting spot and diluting their nectar to fit through extra long proboscises. New research shows that butterflies have more tricks at their disposal. When they fly, they build up a positive charge. That static electricity attracts negatively-charged pollen so intensely that the pollen can JUMP a quarter of an inch off the flower’s anther, to land on the butterfly. Bees have been shown to do this as well but the next time you hear someone malign our scale-winged friends, remind them that butterflies are more than a nice set of legs.

• Axiom research published a new survey on lawn fertilizers that illustrates the vast gulf between what people want and what the market provides. Most people (70%) are concerned about synthetic fertilizers causing ecological and physiological harm, but about half of respondents say they’re using them on their lawns, as well as insecticides, herbicides, and fungicides. But there’s hope in that the other half of people use natural products and another 25% want to. When asked straight up what they want in their fertilizers, only 4% said synthetics. Time to talk to your neighbors.

• If you’re working to keep neonics and other pesticides off your land, maybe reconsider that tulip planting? Laura Fenton reveals that safe bulbs are hard to find. Fully organic bulbs aren’t available in the US yet, but Hudson Valley Seed Co doesn’t use any systemics, while White Flower Farms and Brent & Becky’s are free of neonics.

• Gardens are “fundamentally curated spaces of encounter, places for collective growth, and indispensable sites for nurturing hope” writes Giovanni Aloi in this reflection on the gardens of bygone artists. From Derek Jarman to Frida Khalo, it’s only been recently that these botanical works are recognized alongside those that can hang in a gallery. Artists now use land as a medium regularly, “no longer inviting us to build idyllic retreats from the hustle and bustle of city living, these artists, are determined to unearth the true potential of gardening as a thoroughly alive, critical and radical practice.” Snap snap.

• New trend alert! “Depaving” is sweeping cities around the globe and fairly self explanatory: volunteers rip out concrete, asphalt, and grow plants in their place. Cities can help by sending a “tile taxi” to pick up old pavers. A group in Portland has diverted 14 million gals of rainwater and a team in Belgium, where the practice is called “ontharden,” has de-paved >70k sq ft. “It feels like you're liberating soil.”

• The reward for making it to the end this month is truly special: cocaine! Haha! But truly, Coca is an incredible plant that has been used by Andean peoples for >8,000 years. That it is currently illegal to grow in its native range is seriously lame and it’s a wonder that these racist, hackneyed policies persist to this day (thanks CIA). Bolivians have organized to change the law and it looks like they might see justice soon, but this post is about the plant itself, four species in the genus Erythroxylum, who produce cocaine as an insecticide. Kew researcher Oscar Alejandro Perez-Escobar studies Coca taxonomy amidst intensive agriculture, armed conflict, and deforestation. He found that it’s quite difficult to do! Aforementioned disruptions threaten conservation and research, but it seems that the species are quite plastic, with gene flow blurring our imaginary boundaries between them.

• And YES, I did look up caterpillar specialists and was delighted to find Eloria noyesi, the Coca Tussock Moth, who sequesters pure cocaine while they eat the leaves. The one public study (from 1981) on the moth’s ecology speculates that the caterpillars may regurgitate cocaine-infused liquid as a defense mechanism, but we don’t know any more because the USDA attempted to WEAPONIZE this poor creature so they could drop caterpillars from airplanes as biological warfare agents and all further research is classified. And you thought this newsletter was about gardening.

UPCOMING EVENTS

• Margaret and Ken’s Virtual Garden Club

  September 19

  Virtual and open to the public

  Lucky us, we get to hang out with Ken Druse and Margaret Roach to talk gardens. I’ll be kicking off their virtual garden club with an entire lecture on mulching and cutback, with a generous Q&A.

• Washington State Master Gardener Advanced Education Conference

  September 27 - 28

  Virtual and open to the public

  I’ll be delving into specific techniques for ecological gardening in this instructive fall webinar.

• American Horticultural Society Lecture

  November 7

  Virtual and open to the public

  Get excited for Adventures in Ecological Horticulture! I’ll share my experience attracting butterflies and people to public land, and why they’re both so important.

• Native and invasive plants with Rebecca McMackin & Mark Weathington

  December 12

  Online and open to the public

  Mark and I both lectured at the Woody Plants Conference this summer, promoting wildly different opinions on the benefits and risks of native and exotic plants. Sadly there was no forum for conversation so the Morris Arboretum has kindly offered to host us, as we delve into what may even be described as a debate. Can’t wait.

www.rebeccamcmackin.com