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Milkweed guides

Everything practical: getting seed to germinate, when to sow, what is eating your plants, and how to build habitat that works.

Growing

Growing How to plant milkweed seedsMilkweed seed is easy once you understand one thing: most species will not germinate until they think winter has happened. Everything else is detail. Growing When to plant milkweedThere are two good windows for milkweed and one bad one. Fall suits seed; late spring suits plants; midsummer suits almost nothing. Growing Collecting and storing milkweed seedTime the harvest wrong by a week and the seed either is not ripe or is halfway across the county. Here is how to get it right, and how to de-floss a pod in thirty seconds. Growing Milkweed pests and problemsAlmost nothing you find on a milkweed needs killing. The bright orange aphids are the exception people ask about most, and even they rarely matter. Growing Buying milkweed seeds and plantsThe two things that matter when buying milkweed: is it native to your region, and has it been treated with systemic insecticide? Everything else is preference. Growing Growing milkweed in containersMilkweed in a pot is entirely possible if you respect one thing: these are deep-rooted plants, and depth matters more than width.

Monarchs

Monarchs Milkweed and monarch butterfliesA monarch caterpillar can eat milkweed and nothing else. Remove milkweed from a landscape and you remove monarchs from it. That is the whole conservation story in one sentence. Monarchs The tropical milkweed problemIt is the most widely sold milkweed in America and, south of the frost line, the most damaging plant a monarch gardener can buy. Monarchs Creating a monarch waystationA monarch garden is three things: enough milkweed to raise caterpillars, enough late nectar to fuel the migration, and no pesticides. Everything else is refinement.

Identification

Identification How to identify milkweedEvery milkweed shares one unmistakable flower structure. Learn to read it and the genus becomes obvious; after that, leaves and habitat do the rest. Identification Milkweed lookalikes and how to tell them apartMilky sap is not enough. Several unrelated plants bleed white, and two of the lookalikes actively kill monarch caterpillars. Identification How milkweed pollination worksMilkweed does not shed loose pollen. It packages it into saddlebags that clip onto an insect leg like a piece of luggage, and it does this so awkwardly that fewer than one flower in a hundred sets seed.

Safety

Safety Is milkweed poisonous?Milkweed is genuinely toxic, but the practical risk in a garden is low. The species that cause real harm are the narrow-leaved ones, and the usual route is contaminated hay.

Ecology

Ecology Everything else that lives on milkweedMonarchs are the famous tenant, not the only one. Roughly a dozen insects in North America eat milkweed and almost nothing else, and most of them wear the same orange and black warning colors.