Rose Milkweed - Asclepias incarnata - is the perfect perennial plant for Monarchs! Also known as Swamp Milkweed, Red Milkweed, Marsh Milkweed. KEEP IN FRIDGE 'TIL TIME TO GERMINATE! Germination: Pour 180F water over seeds, soak overnight, or 24 hours. plant 1/4" deep in moist sand, place in refrgerator for 1-2 months, place outside after danger of frost has passed. These seeds can be directly planted outdoors in fall or winter in hardiness zones 8 and below. One of the keys to having monarchs—for their survival now and in the future—is having lots of milkweed. Because of modern changes, such as suburbanization and Roundup-Ready crops, there's a lot less milkweed than there was in the past. This is a disaster for monarchs since monarch caterpillars can eat nothing but milkweed. No milkweed, no monarchs We want lots of monarchs, so we plant lots of milkweed for them to lay their eggs on. We've tried to maximize our milkweeds in a number of ways—especially since it's sometimes difficult to find them for sale or at least to find them for sale at an affordable enough price to buy more than just a few.