Brenda and I have just returned home (Midhurst, Ontario) from helping out at the Monarch Teacher Workshop in Connecticut. When out for the field trip on the second day of this 3-day workshop, we visited the home of one of the local West Hartford teachers, Mary, who leaves a patch of milkweed in her lawn. In the photo, some of the teachers attending are looking for eggs and caterpillars on the milkweed plants.
They found quite a few, because this patch contains nice fresh plants. Mary had mowed the milkweed down in early July and it has now grown back providing good plants for egg laying and for feeding caterpillars. Mary also has milkweed growing at the other side of her house but it was not cut back, so it provides more mature plants with seed pods.
Both patches also provided a good selection of other members of the milkweed community such as milkweed bugs, milkweed leaf beetles, aphids, etc. On some plants, Mary had used a mesh bag enclosure that she purchased from Monarch Watch. It protected the caterpillars that were on the plant from pedators.