We transplanted common milkweed from the roadside in Manitoba in August '06. Not a great time to be moving plants. But it came up in the spring and in May Mrs. Monarch visited. The plants have now taken over a good portion of our garden. It comes up in the echinacea, the monarda, the lilies but hey! what a great place for the mature cats to live next to. I have purchased some hybrid asclepias and pretty though they may be, and attractive as nectar plants, they just don't have the leaf mass to support a thriving Waystation. Without exception, eggs hatched and larvae grown on the hybrids (non-invasive varieties) have to be moved to the common milkweed for maturing.
I have found there is a very small window for potting up common milkweed. In the spring when all plants want to propagate, you can dig it up and plant it anywhere with some certainty of success. Two weeks past that window and the root hairs seem to have disappeared and it just ain't gonna work. I have potted up many plants, in fairly smallish pots, and while they do survive, they don't seem to thrive. BIG pots are the answer. I dig up a newly emerged plant, track it back to a longer root and literally wrap it around inside the pot, fill it with earth and wait for the shoots to pop up. They STILL don't seem to grow with wild abandon as the plants directly in the garden, but they're great for 'baiting' the Monarchs. The leaves on these potted plants remain smaller and tender, attracting the female Monarch depositing her eggs. I then cut a small portion of the leaf, move it inside and let her continue to deposit more eggs. The garden-grown plants have leaves by now that are hard and leathery, NOT attractive to the Monarchs. It seems that they only deposit eggs on tender plants which the newly emerged larvae can eat through. The potted plants provide that texture of leaf.
Southern Ontario, Manitoba, and northern Minnesota have an abundance of roadside common milkweed. In our little pocket of northwestern Ontario, we don't or didn't until we moved ours in. Our growing season just doesn't seem to be conducive to produce the beautiful pods of blowing, whispy seeds with their sparkling umbrellas. So it's a bit of a surprise to find new plants 40' from the original plants. I do believe James Price when he said the new shoots can surface 10’ from the original plant. My garden proves that.
I’m going to set up a Picasa web album and share some photos of our garden and the striped creatures which have taken over our lives! I had no idea this could become such an obsession and SO labour intensive!