The Rise and Fall of the Cup Plant: Lessons
from the Pollinator Garden

By Maureen Williams

🌱 2011 – Planted

📏 2012 – 6ft Bloom

⛏️ 2019 – Excavation

“Cup” at its finest in 2014.

Based on personal experience with the Cup Plant – Silphium perfoliatum.

2011 was the year I met Cup; it appeared on a list of plants recommended  by the Native Plant Nursery at Lemoine Point to feature in our Pollinator Garden  project. The plan was to plant a collection of native and other hardy perennials that pollinators would love and humans would appreciate enough to consider planting in their own gardens. Thus, the project was named a Demonstration Garden.

The baby cup (12 inch seedling) was planted in September 2011. A year later, it was the tallest plant in the garden at about 6ft with a crown of yellow flowers hosting many bees, a pollinator friendly success story! As it grew, it formed a tidy clump and really impressed us all.

“Cup”, a Garden Giant, Requires Too Much Staking & Care

Alas, the story shifts gears! In 2019, our volunteer team decided to remove “mother Cup” because of extensive maintenance.

  • Stakes and ties to keep it upright in spring
  • Cutting back old stalks at fall clean-up
  • Removal of many cup babies
Gardening Kingston Volunteers Excavation Team In Action, November 2019!

The moral of the story: In the right place (maybe by a farm gate) Cup is an attractive  pollinator-friendly plat BUT it will overpower in most gardens. For that reason, we are no longer recommending it as an addition to your garden.

2020 update. There are a few baby cups still sprouting!

Garden Takeaways ⚠️

  • Aggressive Growth: Cup plants quickly overpower average gardens as it forms large colonies that crowd out neighboring plants.
  • Prolific Self-Seeding: The cup plants produce high volumes of seed that birds and wind distribute. The result is hundreds of tiny hardy seed all over your garden every spring.
  • Space Requirements: A cup plant can reach 8-11 feet tall and spreads about 3-5 feet wide.
  • Strategic Placement: Cup plants prefer full sun with rich soil that is consistently medium to wet but will grow in drier conditions and produce a shorter plant. Because it can spread aggressively, consider it for spacious, naturalized areas.