Answer: Butterfly Milkweed (Asclepias tuberosa interior) typically grows only about 3' tall so I'm not sure what's up with yours! Pruning and pinching back milkweed is fine and does promote a bushier plant with more tender leaves that attract laying female butterflies. But don't overdo it if you want flowers and, eventually, fertile seed pods. Most milkweeds have a flowering period, and if you pinch off the budding tips they may not flower well or will flower too late to form viable seed. Pinching once early in the season and a second time above the flower stalks might be a good compromise and should keep your plant smaller next year, but this year you may have to sacrifice some flowering to reduce the size of your plant. Best wishes with your butterfly milkweed!
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