If you live in Southern Canada, Eastern or Southern US, or Mexico, you may be in a place where Black Swallowtail (also called Eastern Black Swallowtail) butterflies live. These beautiful large butterflies are one of over 500 species of swallowtails, and one of the more common ones to be seen in urban areas of their habitat.
Swallowtail butterflies in general are large with bold colours, and most have the characteristic ‘tail’ that looks so similar to the tail of a Swallow (bird). Although their populations aren’t in danger at the moment, watching them grow from tiny egg to butterfly is a magical experience that I believe helps us to connect with nature. If you’re interested in learning how to care for these beautiful creatures, keep scrolling.
1. Find the eggs
They will look like tiny, perfectly round (except for a SLIGHT flat edge where they attach to the plant), creamy white-to-yellow balls about 1mm diametre. Black Swallowtails lay their eggs on plants related to carrots:
carrot greens
dill
fennel
rue
golden alexander
Queen Anne’s lace
celery
(and in some areas – citrus trees!)
2. Bring the eggs inside
Although many eggs will hatch in the wild, the little round eggs are a perfect ‘protein pop’ for many snacking predators, so you will increase their chances of survival by sheltering them indoors.
Many of the plants that eggs are found on do NOT like to be removed from the garden, and will quickly wilt. One thing that you can do to help is to plant a pot of the caterpillar’s food, then lay found leaves with eggs on top of the healthy potted leaves. When the egg hatches, it can quickly crawl away from the wilted leaf and start eating the fresh, healthy leaf. Another thing that you can do is to replenish picked leaves often, and try to sustain them for longer by placing the stems in a vase with water.
3. Store the eggs and caterpillars
I usually keep these caterpillars in open-topped jars and on greens rising our of vases. Unlike milkweed leaves for Monarchs, which don’t wilt that quickly in an enclosed environment, the food of the Black Swallowtail will dry out and rot easily. As long as I keep the caterpillars well fed, they stay with their jar or vase. If you really don’t want them to escape, consider placing a cover (like an upside down tote container) over your set-up.
4. Feed the caterpillars
In general, the caterpillars want to eat the same food for all of their lives. If you find an egg that was laid on fennel and starts to eat fennel leaves, it won’t be very happy if suddenly you try to feed it carrot greens. They also eat A LOT. Check that they have enough to eat at least twice a day.
5. Let the caterpillars hang from something sturdy
A stick works well! Thin enough that the caterpillar can reach around it to attach it’s silks, but sturdy enough that it won’t collapse. The caterpillars are great at attaching themselves to many places, though. If they get loose in your home, they may attach themselves under chairs or tables or even along power cords! Placing a lid loosely on a jar containing the caterpillar and some food can prevent them from ‘going rogue’.
6. Release the butterflies
Almost as soon as they hatch, the butterflies are ready to go outside – but they may hang out nearby for a long time if conditions are damp. Take advantage of their hesitation to take lots of pictures!
Throughout our summers here in Southern Ontario, Black Swallowtails will go through 2-3 generations, and the last pupae set will overwinter until Spring. You can start finding eggs as early as a few weeks after the last frost, and keep finding them until just a few weeks before the first. Keep those food sources growing in your garden, and the butterflies will keep coming back for more – hopefully helping to pollinate your other plants at the same time!
My family is known to brag about our environmentally-conscious produce. Pumpkins served in pie form at Thanksgiving have been smugly referred to as ‘zero footprint’, and we’ve all thought ourselves minor climate heroes for having a second slice. Are we just greenwashing ourselves?
Recently, the largest study to date comparing urban ‘low tech’ agriculture to conventional agriculture was published(1), largely from University of Michigan researchers. The authors compared conventional (i.e. what we usually think of) farms with urban farms, home ‘kitchen’ gardens, and community gardens – and they concluded that on average, the carbon footprint of food grown in cities is inflated six-fold. Six times WORSE for the environment to grow it yourself on what would otherwise be a boring, water guzzling lawn.
What does this mean for climate-conscious home gardeners? If we care about planetary health – should we just throw in the towel and buy all of our food from conventional growers?
I give you my take on the whole thing, and why there’s plenty to keep gardening for, in this video:
Suffice it to say, the headline is dealing with average carbon footprint, and “average” has a big spectrum. Consider two home gardeners each growing a tomato – Brandy and Roma. Now, Brandy and Roma have very different biases and backgrounds, and that leads them to make different choices in their quest for yummy backyard tomatoes:
Brandy
Roma
Builds a new garden bed in a sunny spot
Reuses the garden bed that’s been there for 10 years
Drives across town to buy a seedling
Starts plants at home from saved seeds
Buys new gadgets to protect the young plant, like a water collar and clear cloche
Waits until later in the season to transplant and doesn’t buy gadgets
Buys a flimsy unrecyclable trellis that will only last one season
Uses natural fibre (compostable) twine to make a string trellis
Buys soil, synthetic fertilizer, tomato food spikes, and a new watering can
Adds a layer of homemade compost when planting, feeds throughout the season with compost tea
Waters with municipalpipedwater
Waters with collected rain water
So many other little details can also be different between these two growers. Maybe one uses grow lights; maybe one gets attacked by hornworms and loses half of their plants; maybe one uses recycled yogurt cups for seedlings, and the other buys new Styrofoam (ugh!!).
The point is, even without a published study it’s easy to see that some urban growing choices are better for the planet than others. The same is true with conventional growing.
What, then, is the takeaway from this study?
Essentially they found that there are three big drivers of urban agriculture’s climate impact – or, flipped around, three ways we can optimize our urban gardens.
Reuse infrastructure. Typically, conventional growers use the same equipment and infrastructure for decades, while a home gardener may be more likely to use beds or outbuildings for only a few years. This is the biggest driver of urban carbon footprints; so if you change NOTHING else, but extend the lifespan of your gardening space a little longer (or, recycle other materials to build your garden space), you can drastically reduce your urban gardening environmental impact.
Self check – last year the wind broke one of my arbours, and I couldn’t fix it, so it unfortunately went in the trash… and I keep adding to my garden beds every year… and I replaced existing garden beds with my metal raised beds. BUT, those beds were falling apart, and I reused the wood where I could. And I bought a second hand arbour to replace the one that broke. And I’ve made many of my garden bed borders by reusing old stone. Not all bad, but just to be sure I’d better use my garden for at least another 40 years!
Grow things that are hard to store. Food that is:
flown into our shops or
requires extra packaging or
needs a greenhouse and lots of fertilizer to grow or
is as likely to be discarded from the store as sold
…is all high conventional carbon cost. If we grow that food ourselves, it’s overall better for the environment.
Use ‘urban waste’ to nurture the garden. Really, this means to amend existing soil with high quality compost and collected water. They make a point that poorly managed compost is no good – that’s actually going to increase greenhouse gas emissions. Luckily it’s pretty easy to make a good compost heap in urban settings (the key is usually good aeration!). See my How-To for more details!
If you grow a tomato in your backyard in soil that you imported, with fertilizer that you imported, and with water that your pipes are importing – is it really ‘locally grown’ anymore?
The study is also quite optimistic that there are a lot of climate benefits to urban agriculture, despite the huge footprint (on average!). Extending their discussion:
People who grow their own veggies tend to consume more veggies, and therefore less meat and dairy(2). One kg of beef generates 60kg of CO2e, by far the highest of any of our foods – when we eat a little less beef and other meats, we reduce the overall carbon footprint of the things that we eat.
Spending more time in nature, as naturally tends to happen when people garden, also improves physical and mental health(3). Healthcare has a huge carbon footprint, it accounts for 5% of Canada’s annual greenhouse gas emissions, so if gardening improves physical and mental health and may lessen the burden of healthcare even a little, there are carbon savings there as well.
Looking even more big picture, research also shows that when people do more to connect with nature, like gardening, they are more likely to address their carbon footprint in other ways(6). I know that’s true for me, the more time I spend in nature, the more I realize the importance of planetary health.
And I also worry about my health, and my family’s health. I’m careful with the food I grow, not to contaminate the soil or spray it with noxious pesticides, because I don’t want to eat that. If all of my plants were ornamental, maybe I wouldn’t be so careful – and my pollinator friends would be more likely to get sick from my flowers.
With all of that – is it better for the environment to leave food growing to conventional farmers?
No.We should still be growing food in urban spaces, but this study highlights that there’s a lot of room for improvement. The average food produced in urban agriculture has a higher carbon cost than the average conventional farm food, but some of the sites that they studied were more carbon friendly than conventional farms. We need more urban agriculture like that, with slower infrastructure turnover, greener growing practices, and more recycled water and truly local nutrients to feed our plants.
We can always try to do better, in all spheres. That seems to be the point of the study. We shouldn’t just assume that we’re being better for the environment when we grow in our backyards, we need to continue to be environmentally mindful in our choices and to continue to research so we can learn and optimize. Canadian gardens, and other areas with shorter growing seasons, were notably absent from the data! Are there more potential gains when we’re growing our own food up north? Or more pitfalls?
One more concern raised, before I sign off; if we have a big shift to urban agriculture, and perhaps it becomes less desirable to have as many conventional farms, we have to consider what may happen to that land and if that would be a positive environmental step. With our growing population and increasing global hunger, and increasingly vulnerable food supplies, I’m not sure if that risk will come to pass, but it’s worth thinking about.
So, I’m still growing in my urban setting, and still feeling like I’m overall helping planetary health, but with lots of notes for how I can do better going forward. And for you, however your garden grows, keep growing as a gardener.
Citations:
Comparing the carbon footprints of urban and conventional agriculture (DOI 10.1038/s44284-023-00023-3) – Hawes, J.K., Goldstein, B.P., Newell, J.P. et al. Comparing the carbon footprints of urban and conventional agriculture. Nat Cities (2024). https://doi.org/10.1038/s44284-023-00023-3
Puigdueta, I., Aguilera, E., Cruz, J. L., Iglesias, A. & Sanz-Cobena, A. Urban agriculture may change food consumption towards low carbon diets. Global Food Security 28, 100507 (2021). ; Scarborough, P., Clark, M., Cobiac, L. et al. Vegans, vegetarians, fish-eaters and meat-eaters in the UK show discrepant environmental impacts. Nat Food 4, 565–574 (2023). https://doi.org/10.1038/s43016-023-00795-w
White, M.P., Alcock, I., Grellier, J. et al. Spending at least 120 minutes a week in nature is associated with good health and wellbeing. Sci Rep 9, 7730 (2019). https://doi.org/10.1038/s41598-019-44097-3;
Hunter Mary Carol R., Gillespie Brenda W., Chen Sophie Yu-Pu. Urban Nature Experiences Reduce Stress in the Context of Daily Life Based on Salivary Biomarkers. Front. Psychol., 04 April 2019 – Sec. Environmental Psychology Volume 10 – 2019 | https://doi.org/10.3389/fpsyg.2019.00722 ;
Caoimhe Twohig-Bennett, Andy Jones, The health benefits of the great outdoors: A systematic review and meta-analysis of greenspace exposure and health outcomes, Environmental Research, Volume 166, 2018, Pages 628-637, ISSN 0013-9351, https://doi.org/10.1016/j.envres.2018.06.030.
Caroline M.L. Mackay, Michael T. Schmitt, Do people who feel connected to nature do more to protect it? A meta-analysis, Journal of Environmental Psychology, Volume 65, 2019, 101323, ISSN 0272-4944, https://doi.org/10.1016/j.jenvp.2019.101323.
For those bitten by the bug, it’s one of the most exciting times of the year – choosing what you will grow next season!
I am constantly on the lookout for new companies, new varieties, new techniques – whatever is going to evolve my gardening skills and get me through the winter blahs! So, by now I think I’ve done enough perusing, buying and trying to have some solid favourite companies.
A few years ago my neighbour, a fellow gardening-enthusiast, gave me some bean seeds. She told me that they grew a kind of pole bean that tasted better than a typical pole bean. She had grown and saved seeds from these beans for years, and she called them “ugly beans”.
These beans are now the only kind of pole bean that I grow, year after year. We eat tons of the large flat pods, steamed and then tossed in butter and salt. When we’re a little sick of beans (or, sick of the kids complaining that we’re having beans with every supper!), we dice and pickle them in a simple refrigerator brine. Then, we let the pods mature and the beans plump into navy seeds, to save for next year (with leftovers for winter chili).
Gardening gifts, the gifts that keep giving and multiplying, are one of my favourite social interactions. A few years ago a friend gave me a squash, and when we ate the squash I saved some seeds to plant the next year. In retrospect, ONE plant would have been plenty, and our freezer still has some of that subsequent harvest to prove the point. But, I still have the seeds, and as soon as I find some inspiring new squash recipes I’ll be starting too many squash plants again, more connected to those little seedlings because of their origin story.
Saving seeds, too, helps to preserve seed biodiversity. As many seed companies over the last century or so have concentrated on quality seeds over quantity, many varieties of fruits and vegetables have disappeared. (See this article for some staggering statistics!) Most grocery stores carry an even narrower collection. There are hundreds of varieties of edible bananas in the world, but my kids’ alphabet books only show the standard Cavendish kind. In this way, trying to grow and save the heritage of different plants feels a bit like preserving a culture – and then passing it on.
When I started saving seeds for holiday cards, my thinking on the subject was much more superficial and my emotional connection to seed saving was much less developed. It started as a fun novelty, and a little interactive gift to send across the country – and it still is that, I still like saving and sharing seeds for the same reasons. But, this year, I decided to choose seeds that may or may not be available through a seed catalogue, and that were the descendants of someone else’s gift to me. It doesn’t have to be sentimental, but for those of us who like a little sentimentality as winter settles in, there it is. I still call them “ugly beans”, but they feel pretty darn beautiful.
Planting instructions:
If direct sowing, wait until the soil has warmed so the seeds don’t rot (10C overnight). Plant next to a tall trellis or fence – they will climb up to 10ft tall. They love sunshine, and like to be generously watered but need free-draining soil to keep from rotting.
Avoid planting onions, leeks or garlic nearby.
Harvest beans when the pods are green and flat, just before or just as the seeds start to bulge. Harvesting early and often will increase your yield.
If left, the pods will mature and start to yellow as the bean seeds will turn from green to a dark navy. They can be removed from the pods and saved for next year, or cooked and eaten like any culinary dried/mature bean seed.
In the garden (as in life?), I tend to take on slightly more than I can comfortably handle. It’s hard to curb my enthusiasm for garden adventures. I always want to try something new, improve my efficiency, and ‘wow’ my family. But, perhaps expectedly, in the hum of the busy season, this often means my careful plans from the winter are entirely forgotten.
Carrots pop up unexpectedly because I didn’t mark it down when I planted them; fruit trees get tired of waiting for me and start to prune themselves; varieties of peppers are forgotten, and the saved seeds start being labelled as ‘the ones that were good in soup’. It all devolves into improv.
This year, I attempted to grow mini corn (as are often seen in stir-fries). When I selected the seeds, it was January. I might have re-read the instructions when I started the plants, in May, but May is already getting fairly frantic and I likely didn’t. By August I was harvesting my cobs, and the effects of over 6 months of progressive memory fuzziness started to show.
The cobs were well pollinated, small, yellow – they looked pretty perfect! But they were hard, and overly chewy even when cooked for a long time in extra liquid. They seemed like a dud, but not just because we didn’t like the variety… something was off.
This week, I finally figured it out.
Per the seed packet… one is meant to harvest mini corn BEFORE they are pollinated. And if you wait for them to be pollinated, well then they become a popcorn variety of corn.
I had saved one small final cob of the stuff, I can’t even remember why… perhaps I thought the chickens would enjoy it? But today, I de-cobbed the kernels and saved them for seed. A very small extra handful, I also popped on the stove (without a lid – another ill-advised shortcut. Those things get some air!).
So, haste makes waste and I lost a year… but I’ll never forget when to harvest mini corn, now! A bonus is that I managed to save more seed than I had originally purchased. I’ve learned from my mistake, but probably not enough to prevent myself from making similar mistakes in the future!
Here in Ontario, we’re just barely at the tail end of summer. The leaves have started to change colour, typical for us in early to mid September, and the weather is still in the 20s (C) during the day and above 10C overnight. Pepper flowers are still coming, my roses are putting out new blooms, and my watermelons are trying to set a new round of fruit.
But it’s October 6, only a few days before our typical first frost date.
It would be awesome if it weren’t so terrible.
Climate change is an anxiety provoking thought, one that I dwell on a lot. It’s hard to know if it’s good to think about it a lot, because it makes me really environmentally mindful of my choices… or if I’m pushing myself more into climate anxiety and paralysis. My daughter recently asked me “what if there isn’t clean water to drink when I grow up?”. I didn’t have a good or convincing answer for her, because privately I’m concerned about the same thing.
I can’t end this entry on that note, so my little bit of hope is that today I learned the monarch butterflies are no longer considered endangered. I like to think my little garden and caterpillar hatchery is partly responsible. Now to go help the puffins…
Wow, a milestone! Somehow the excitement at 1000 is familiar – it feels like the same excitement I had at 16, at 100, and at 500. The number grows, the views increase, and I feel super lucky to get to “talk” to so many people about one of my passions.
My YouTube channel is many things to me – it’s a way to share my love of gardening, a way to ‘pay it forward’ for all of the gardening advice I’ve received over the years; it’s an ongoing exercise in how to present information so that it is clear, entertaining, and accurate; it’s a growing community and a way to connect with people I otherwise would never meet. I love working on it with my husband, and I’m looking forward to whatever the next garden season brings.
Another person’s trash, another person’s treasure… this year my seedlings are falling victim to pillbugs. Three garden beds are overflowing with the creatures. What is usually benign to beneficial has become malignant. They’ve eaten pepper, tomato, eggplant and broccoli seedlings. They are not interested in the dill, which is the one plant I actually have in abundance.
So, I’m setting the beer traps and wrapping the new seedlings in collars and trying to figure out what happened. Last year there were a few trying to eat some of my potatoes, but nothing like this.
My best guess so far goes back a little ways. I think, maybe, I planted something in those garden beds a few years ago that was particularly attractive to pill bugs (also called potato bugs, roly polys, or maybe wood louse, depending on who you ask – and some may disagree with the accuracy of alternate names!).
Pills bugs live a remarkably long time, I’ve learned – a few years. Not quite the same scale as a fruit fly. They also don’t start laying eggs right away, it takes a few years. Hence my timeline – I unwittingly attracted them, and now they have exponentially increased their populations.
What attracts pillbugs? Dead and decaying things. I don’t trench compost, but I do often leave old plants in the garden over the winter. I think that might have done it, I think I had some old broccoli or other brassica with a huge stalk, and I didn’t cut it off at the soil level when I had the chance, so the whole thing started rotting in situ – beaconing the pill bugs to come and feast, and move into the neighbourhood while they’re at it.
Lesson learned – including that the plants I left over the winter in OTHER beds are likely to have this issue next spring. The tops of my old plants, like the pill bugs, belong in my compost.
I’ve been forgetting to write, so a brief catch-up to where we are: almost all crops are now in the garden, with some succession seedlings started, hardening off, etc. Still a few radishes and peas to plant, and lots more beets and carrots. My first soft-neck garlic has already fallen over! Asparagus and hosta harvesting is over, and rhubarb is starting to take off. Yesterday we inventoried the freezer stash to make sure we menu-plan appropriately and clear the backlog!
It’s been a fairly typical spring with one glaring exception. Our last average frost date is around the last week of April. I planted a lot of my cool season, frost-tolerant stuff just before then, including cabbage, pak choi and lettuce. I also had a little over-wintered kale that was starting to grow. Shortly after that, still in April, we had unseasonably warm weather for a few days, then back to our usual April/May climate. The warm jolt was too much, the kale, choi and cabbage all bolted.
Bolting, or flowering, happens for one of two reasons. One is that a plant is mature and ready to produce seeds, and the other is that the plant has been very stressed and thinks it’s going to die, and it wants to quickly clone itself before it kicks the can. Too hot, too cold, too dry, too wet – any of those things can spook plants and cause them to bolt. Often they bolt quickly if they are planted out too late, when the weather is warmer than they’d prefer.
A few weeks after that, WELL into May and a full 3 weeks after our usual average last frost date, we had a week of very cold nights – and it frosted! My tomatoes were already out – even some peppers were out! I’m very thankful some cloches protected the majority of them, only lost 1-2. But, shortly after, one of my tomatoes started flowering! It’s barely got two sets of leaves. I think it thinks we’re headed into fall and it had better get a move on.
Other gardeners have noticed other effects from the bizarre weather. The blooms on their peonies aren’t as lovely, or the buds on their fruit trees fell off prematurely. Last year it was something different – we don’t often get hail, but it fell with a vengeance on apple orchards, blasting tiny holes in many of the premature apples. The year before it was something different again, and of course other areas get increasingly severe floods, wind storms, fires, etc.
The increasing frequency of these unusual weather whims are an uncomfortable reminder of our global food supply’s vulnerability. It takes so little to wipe out a field of produce, or thousands of fields. For me, the bolted plants can go to the chickens – but that’s not an appropriate or available solution for the world.
It’s April 1, and consistent with the day’s moniker I have planted my first seeds in the ground.
Around here I can expect my first frost-free 24hrs around the beginning of May, but it’s not unusual to have weather anomalies. Days may be below freezing, or they may creep into the high Celcius teens. Local wisdom is often quoted as saying not to plant out until after May 21, although experience has taught me that’s a little too conservative if I’d actually like a harvest before frost hits on the other end of the season.
A few days ago, in a frenzy of clearing last year’s weeds, I planted some climbing peas in the ground. I’ve done this before and gotten no time or yield gain whatsoever from my impatience, but it still scratched an itch to do it. Whenever I know I’m wish-planting I have a back up plan, and in this case I reserved most of my seeds to fill in the gaps or sow-anew.
This morning I put out three kinds of radishes, my yellow beets, and a bok choi seedling. I’ll sow the radishes every two weeks until early June, some more beets in 3 week intervals, and some more bok choi and other brassicas over the coming days. I like to space my early transplants out so if a squirrel or slugs find them and think they’re a tasty treat, hopefully they only get 1-2.
The seeds that I started inside about 10 days ago are doing as predicted. The tomatoes and peppers are slowly sprouting, the melons and squash are already looking like they’d prefer to be in the garden, but they somehow need to wait 6 weeks. Good thing that family transplants so well (they don’t!). There’s something comforting about making the same mistake every year, even knowing that I’m making it as it happens. Plants love to grow… for most of them, it will turn out fine despite me.
