Raising Monarchs, routing aphids

It was a heart-stopping moment.

I was cleaning the Monarch caterpillar trays and Ami, the new puppy, grabbed a milkweed cutting from the container used by caterpillar #9 and proceeded to strip all the leaves off. I naturally was terribly upset – not only because of the apparent demise of #9, but also because I thought Ami might get sick; #9 was particularly large and juicy. Then I noticed #9 on another cutting in the same container. Relief! and a more careful separation of canine and cat.

My adventure with Monarch juveniles starts 10 days ago when I get back from a week away and notice that the Swamp Milkweed in the bog garden is in glorious flower, but also looking a little droopy. I take the hose over and started to trickle water in, thinking the area had dried out. It’s a busy spot. A Monarch butterfly hovers around me, landing on the flowers. Many bees and syrphid flies are feeding there too. Then, I see the aphids. Every stem right up and into the florets, is thickly coated with a layer of tiny orange insects.

I go to consult the internet and find that this species is Aphis nerii, the Oleander Aphid, aka the Milkweed Aphid. A helpful site called Monarch Butterfly Garden – the work of one Tony Gomez - has a whole page devoted to removal of these creatures. Not only do they weaken the plant, but they reduce the viability of any seed it produces – so immediate action was indicated. I start squirting jets of water at the pests, a method that a couple of years ago I found worked well to remove Milkweed Tussock Moth, which starts off looking a little like aphids. (When these guys got to the stage of looking like hairy caterpillars, I moved them from my potted Swamp Milkweed to patches of Common Milkweed in my field and they continued their lifecycle there.)

The Oleander Aphid is not so easily removed. Day 2 of the battle reveals the infestation is even worse than I first thought, starting right at ground level. But, as Mama Monarch dances around my head, I find a Monarch caterpillar. Back to the internet – which is best, to leave them be or to raise them myself? There’s conflicting advice out there. I find the Monarch Butterfly Garden website to be most specific, with a lengthy list of potential predators – ants, wasps, spiders, assassin bugs, praying mantis, stink bugs and more, resulting in a 95% mortality rate in the wild.

So, the decision is made, I am to be a Monarch Mama. I go back to rescue my caterpillar and in doing so find two more. I bring in three pots of Common Milkweed and place next to them small containers of water into which I put the stems of the cuttings of Swamp Milkweed the caterpillars are on. This is a temporary arrangement while I do battle with the aphids to ensure I have a continuing supply of nutritious foliage. I use paper towels to wipe the aphids off the stems, a small sprayer and a paintbrush to get them out from tighter spaces. The job’s not done by evening. On the other hand, I have found three more caterpillars.

Day 3 - “Beastly aphids not very apparent,” I note in my diary. But #4 has disappeared. We purchase a large plastic container to act as a nursery and move it with all the potted (Common) and cut (Swamp) milkweed to a shady spot outside on the patio. Instead of using the plastic lid, we top the container off with a piece of mosquito netting.

Day 4 – It’s complicated, keeping track of which caterpillar is which, as they move around and sometimes can’t be found. This time, #3 is AWOL. During my daily cleaning routine, I measure them and provide fresh cut Swamp Milkweed. I notice that out in the bog garden, the aphids seem to have rallied and appear to be increasing in numbers. To the attack once again, with paper towels, sprayer and paintbrush (the latter is somewhat effective in flicking the bugs off the flowers). I don’t want to use any chemicals or even soap because Mama Monarch is still in evidence. In the evening, I discover #3 has moved in with #1 on a potted milkweed.

Day 5 – Welcome #7 and #8, found this morning in the bog garden. They measure in at 1.5 and 2 cm respectively. Of the rest, three have reach 3 cm and look exceedingly plump and healthy. All the others are 2 cm or more.

Day 6 – More newbies - #9 and #10 - to join the gang. Meanwhile, I can’t find #5 and #6. It’s a hot and humid day and outside, the aphids keep on coming. All the new shoots are coated with them. But removal is easier now I have drastically reduced the population and know where to look. I hear from a Return of the Native customer who is also raising a Monarch family that it’s important to put the caterpillars where they will get sun and wind. “Otherwise they will not develop the ability to over winter or know where to fly to in Mexico!” This makes sense to me and leads to a major operational change. Out with the plastic nursery with solid sides that don’t allow the wind to get in. Instead, I put the cut Swamp Milkweed containers into two large plant trays and cover them with mesh food protectors. The trays go into a flower bed I have just cleared for replanting, it gets sun much of the day.

I decide to get rid of the potted Common Milkweed, the pots take up too much space and only one caterpillar has remained on it. The rest seem to prefer the cut Swamp Milkweed, which looks fresher. According to Gomez, Swamp Milkweed is the species that’s most palatable at the end of the season.

Day 7 - #1, #3 and #9 have reached the 4 cm mark. As for the others, there’s a lot of moving around so I can’t be 100% sure of who is who, but at least no more have disappeared. Every fresh shoot on the Swamp Milkweed plants that I’m clipping to make fresh food for these voracious feeders is covered with aphids. I carefully wipe them off. There are also what look like greyish white aphids – they are in fact the ‘excuviae,’ the orange aphids’ shed skin. Mama Monarch is no longer around but there’s a lot of life (and death) in the milkweed patch – many different kinds of beetles and bugs, including lady bugs - and I come across a crab spider clutching a dead honey bee.

Day 8 was when #9 had his brush with death in the form of a bouncy Golden Retriever/Husky pup. That was close. And one caterpillar, #10, went walkabout on the mesh side of the food protector.

Day 9 - #10 is back in the game, off the wall and shacked up with #8, feeding on some cut Swamp Milkweed. And lo and behold, an extra caterpillar showed up with #7 – so I called him #6. Only #5 remains missing. #1 has reached 4.25 cm. Not bad for the bog garden’s five plants, as a female will usually only lay one egg per plant, to ensure there’s enough food for each one. Also not bad since the females apparently avoid aphid-infested plants.

Day 10 (today) - I find two fat caterpillars on a mother plant outside, measuring 3.5 and 4 cm. I hesitate to bring them into the nursery because they seem to be doing so well, but nearby there’s a nest of wasps, insects that are major predators and parasitizers of these caterpillars. And I know there’s a killer crab spider in the neighbourhood. So I clip the stem they're on and move them. To be sure of not spreading disease, I put the newcomers - #11 and #12 - in a third tray, with another food protector.

So far, so good. But I’m flying by the seat of my pants, learning as I go along and hoping I can do the right thing and give these magical migrants a good start for their trip to Mexico. As for the Swamp Milkweed plants, the flowers are just about over, and I have clipped many off because it’s so hard to get the aphids out from within the little stalks. I don’t think I’ll be getting seeds from these plants this year. Lesson learned: be ready for the aphid infestation early in the year, and nip it in the bud. Coffee grounds at the base are said to be a good deterrent. And early removal the best prevention.

These are the websites I have used
http://monarchwatch.org/rear I have followed Monarch Watch for years (I have one of their waystation signs)
https://monarchchaser.wordpress.com, recommended by a friend, who’s also on this journey.

September hours The Return of the Native nursery will re-open Saturday September 9, 10am-4pm and will be open on Saturdays 10-4 - except for Saturday September 23, when we will be closed. Other times can be arranged to suit your convenience. Email This email address is being protected from spambots. You need JavaScript enabled to view it. or call 705-322-2545 to arrange a time.

New for fall Check the plant list – there have been additions.
Susan Beharriell
- 24 August 2017 at 05:51pm

Well done Kate! Keep up the good work. I also have about 9 caterpillars, but they do move a round a good deal so it is hard to know for sure. Any response from the scientist? Good luck to us all! Susan
Diane Greenfield
- 24 August 2017 at 07:25pm


I have so enjoyed this narrative... my own story just involves disappearing tiny caterpillers that never reach a significant size. The many adult monarchs are probably reporting an unhappy summer despite my having so many goog host plants... now i need to think predators too. Wrens??
Sheesh. Next year......
cheers, Diane.
- 25 August 2017 at 08:12am

I didn't hear back from your scientist, Susan, but if I do, I will update the post.
Oh those wrens... both my bluebird boxes are occupied by fiercely territorial wrens. I am told the solution is to put wren nesting boxes beside the bluebird boxes. I have my doubts....
Cathy Krever
- 25 August 2017 at 12:07pm

This is fascinating. Read it at work - was almost late for a meeting. I felt like I was like reading a novel - I was so absorbed and obsessed with finding out what was going to happen. Can't wait to hear about next year's episode.
Sharon Middleton
- 29 August 2017 at 10:18pm

After reading your saga, I checked a grouping of Asclepias syriaca left to multiply where it really wasn't supposed as I wanted to attract Monarchs. Amazingly I found two - one large and one medium length. Also found a group of Tussock Moth babies and moved them elsewhere also.
Two days later I could not find the monarch caterpillars but found a new wee one 1 cm long! Today I searched and searched but no luck. With a gut feeling I found the two had migrated across a piece of lawn to a row of Hydrangea shrubs in part shade. The large one upside down in a j position and the medium caterpillar munching on a hydrangea leaf about 60 cm away. Must be sisters!
So thanks Kate for alerting me to search for the Monarch caterpillar.
- 30 August 2017 at 02:26pm

You're welcome! Now I am going to go looking on nearby shrubs for my two missing caterpillars
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