Milkweeds and Monarchs

Monarch butterflies have been in the news recently and sadly that’s due to disturbing trends in their numbers and migration patterns. Their numbers have been declining steadily during the last 20 years, alarming those who monitor their populations. One thing is agreed upon, habitat loss both in Mexico and especially in the U.S. and Canada is the leading factor in their decline. Monarchs lay their eggs, and use as their primary food source, a variety of milkweeds. These Asclepias species populations have shrunk considerably, not just due to habitat loss but also due to the increasing use of pesticides in commercial farming. And increasingly, climate change is having a negative effect. Excessive heat can cause some die-off in Monarch populations, adding another stressor to their lives.

The most common milkweed that Monarchs rely upon is Asclepias curassivica, commonly known as Mexican milkweed because of its abundance south of the border. North of the border this plant acts as an annual, dying off when the cold weather arrives, providing one of several triggers for Monarchs to migrate south.

However, there is an increasing trend for this Asclepias to continue to grow and flower in the winter, disrupting this normal migration. Milkweed hosts a protozoan parasite called Ophryocystis elektroscirrha (OE). As caterpillars, monarchs ingest this parasite and when they hatch from their chrysalises they are covered in spores. Infected monarchs are much weaker than their healthy counterparts and don’t live nearly as long. Migrating eliminates many of the sick monarchs, preventing them from passing the parasite along to their offspring. When the butterflies return in the spring, they have new, clean milkweed upon which to feed.

Native Milkweeds

This is where native species of milkweeds come in. There is some evidence that they are less prone to OE and thus less likely to pass it on to feeding monarchs. And native species do go dormant in the winter, thus not tempting monarchs to hang around. There are two excellent native species that experts are suggesting that gardeners can plant – Asclepias speciosa and A. fascicularis. Tough and beautiful, they will naturalize in your garden.

Love the A. curassivicas? There are ways to keep them. As fall lengthens, either cut them back so there is no danger of them blooming or simply yank them out and plant new ones in the spring. They grow quickly.

Monarch info source: For valuable information on Monarch butterflies check out www.mymonarchguide.com and www.monarchwatch.org

And now a few photos from my garden.

Dicentra scandens. I've posted so many photos of this yellow bleeding hearts that I know I'm in danger of having regular viewers rolling their eyes (not again!). But I just can't fathom how this incredibly prolific, exceptionally pretty vine has disappeared from the retail trade. 

Ixia hybrid. Ixias are a fun bulb, there's just no denying it. Check out the hot pink of this one and that's just one of a bushel of colors that now populate the Ixia world. One of the THE easiest bulbs to grow and they naturalize real easy like.

There's blue and then there's blue. Lithodora is blue, with an accent on the royal end of the spectrum. My plant of ten years has finally just about given up the ghost so I decided to start anew. One of my favorite cascading plants.

Tulipa saxatilis. One of the low growing 'species' tulips, saxatlis tulips are fun and pretty reliable. This is the classic pink and gold but other colors combos have appeared in recent years.

Scabiosa 'Fama Blue.' The 'star' of my early spring garden, this pincushion plant produces huge flowers and this one has a rich purple hue. This is my plant's first offering so can't wait for there to be a bushel of them.

Stylomecon heterophyllus. This wind poppy has been a pleasant surprise this spring. I'd never grown it before and wasn't sure what to expect. But it has proved floriferous and there's no denying it's an awfully pretty orange.

Sometimes one's 'victories' can be with common plants, not just with difficult species. This little wine-colored viola just went crazy on the blooming this year and spilled over the ginger pot in a very pleasing manner. I've designated it my 'official greeter,' as it's right at the head of our walkway.

I was 'promised' a zillion yellow flowers on my Hermannia verticillata and that's what this specimen has delivered. The little yellow flowers also offer a subtle fragrance. Now that I know what it does, I'll have to find a place for it in the ground.

Halimiocistus 'Merrist Wood Cream.' This cross between a Cistus and Halimium has one of the great cultivar names (Merrist Wood Cream, what the heck is that?) Well, it turns out this cultivar was raised at Merrist Wood College in 1970 (that's in England for those non-Britphiles). Lovely color.

Speaking of interesting names associated with a plant, this Pandorea pandorana probably makes the top ten list. I mean, Wonga Wonga vine? There may actually be an explanation. This Australian native may be named after a large Aussie pigeon called a Wonga pigeon ( Leucosarcia melanoleuca). 

Clivia miniata. Here's a much prettier photo of my specimen. Okay, here's an example where regular water improved the results 100%. Richer color. More bloom spikes. Happier plant.

There's nothing quite like the inky blues of Phacelia viscida. This CA native starts blooming in March and though the flowering season is short (6-8 weeks) one is rewarded with the most gorgeous flowers imaginable. Plus they feature cool, speckled nectaries.

Homeria ochroleuca. One of the prettiest bulbs that nobody has ever heard of. Hard to imagine why, given it's simple, sunny charms. Another gift from the great pantheon of South African bulbs.

Dutch iris. Though simple and common, I do love Iris of all kinds, even the most common types, the Dutch iris. They simply express joy.

Verticordia plumosa. This Aussie native is a survivor in my garden. Animals have broken off branches and it's been temporarily covered up by other plants. It keeps on ticking, somehow fending for itself.

No doubt that somewhere there's a list of the 20 weirdest flowers available for sale in the trade and if true then those of the Asarum maximum would surely make the list. They're a weird combination of colors (deepest burgundy with a creamy pink center) and the two inch flowers are actually rubbery. Plus they sort of smell. The common name for this plant, related to the flowers, is 'Panda-faced ginger' but I'm sorry I just don't see it. Cool flower though.