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Ministry of Agriculture, Food and Rural Affairs

cup plant

Other Common Names Include:

Carpenter’s weed, cup rosinweed, compass plant, pilot weed, squareweed, Indian cup

Latin Name: Silphium perfoliatum

Plant Family: Asteraceae

Close Relatives: Sunflower (Helianthus annuus)

Uses and Markets: Cup plant is a native perennial to Ontario.  It has been studied as a forage crop and compares well with corn silage.  It is a tremendous pollinator crop, flowering from July to September.  More recent research has looked at its usefulness as a feedstock for biomethane production via anaerobic digestion.

Stand of cup plant during the peak flowering period of late July.Cup plant seed Emerging cup plant seedlingCup plant stem showing how the leaves from “cups” around the square stem Cup plant flowers are excellent sources of pollen for bees.Mature stand of cup plant in late AugustMature stand of cup plant in late August showing plants that are 2 to 3 m tall.Cup plants at the end of the first growing season in November Emerging cup plants showing growth in early spring


Production Life Cycle in Ontario


Hardiness Zone


Special Notes

Cup plant can survive flooding for 10-15 days.

Propagation method

Seed at 10-40 kg/ha.  Germination can be low and seed collected in fall must be stratified for 12 weeks.

Greenhouse Seeding/Propagation Dates

Transplants can be started in March and planted to the field in late May.

Field Seeding Date:

Early May.

Field Transplanting Dates

Late May.

In-Row Spacing
10-25 cm

Between row spacing

40-70 cm

Optimal Soil temperature at planting



No current Ontario fertility recommendations exist. Research and recommendations from outside Ontario do not necessarily apply to Ontario growing conditions.  Research from other jurisdictions shows cup plant yields increase with increasing nitrogen availability, but the rate increase begins to decline at rates above 100 kg N ha-1.   Click here for phosphorus and potassium application guidelines and for more information on specialty crop fertility.

Soil type

Well-drained, sandy soils.

Soil pH

Neutral soils.

Special requirements for growth habit

A packer should be used to ensure good seed to soil contact.  Weed control during the first year is critical to ensure good crop establishment.

Optimal Temperature Range

Temperate climate.

Temperature sensitivity

Freeze tolerant.

Irrigation requirements

Irrigation usually not required.

Days to harvest

Typically harvested in September.

Specialized equipment

Forage harvester.

Harvest Scheduling

Typically 1 fall harvest but double cropping is possible with first harvest in June during initial budding stage.

Hand harvest or machine harvest

Machine harvest.

Quality parameters/grades:

No established grades.

Additional Harvest Notes

Flowers and leaves provide food and shelter to animals and insects (especially bees), and so harvesting after flowering is ecologically beneficial.

Post harvest
Special handling/curing

Crop is ensiled when used as a feedstock for anaerobic digestion.  Storage losses can be reduced by wilting the crop prior to ensiling or by adding silage additives (e.g. formic acid, wheat, oats or maize).

Storage Conditions

Relative humidity (RH): N/A

Temperature: N/A

Air Exchange: N/A

Duration: Indefinitely

Specific pests observed on this crop in Ontario (observations based on limited experience with this crop)

Unknown – limited to no production of this crop in Ontario to date

Other Potential Pests: The following pests have not been observed on this crop in Ontario. However, they are either significant concerns for closely related plants in Ontario, or are reported on this crop in other production areas. This is not a comprehensive list of all potential pests. Not all of these pests will necessarily survive Ontario’s climate, but could potentially survive in a protected environment (e.g. greenhouse, storage facility).

Insects and Invertebrates: In other regions, the larvae of various moths have been found on the leaves and stem (silver Y, Autographa gamma; mouse moth, Amphipyra tragopogonis; broad-barred white moth, Hecatera bicolorata and giant eucosma moth (Eucosma giganteana) as well as the larva of the tumbling flower beetle (Mordellistena cf. aethiops Smith – Coleoptera: Mordellidae), and the aphid, Uroleucon cf. ambrosiae).  The giant eucosma moth has been the most significant pest, attacking apical tissue, flower buds and the rhizome. 

Diseases: A number of fungal diseases, including Sclerotinia spp. (stems),  Fusarium spp. (seeds),  Alternaria spp. (seeds and biomass) and Botrytis spp. (seeds, flower buds).  Other potentially pathogenic species diagnosed from cup plant include the fungi Uromyces silphii, Uromyces junci, Septoria silphii, Puccinia silphii, Puccinia obtecta, Puccinia albiperidia, Ascochytasilphii sp. and the disease Pseudomonas syringae.


*Indicates pests commonly mentioned as causing significant damage or economic loss to this crop in other regions.


Crops grown for biomass can tolerate higher levels of insect and disease damage than those grown for food or ornamental use. There is some concern that biomass crops can serve as a refuge for pests of neighbouring crops. Weed control will likely be necessary during the first one to two years as weeds will compete with establishing plants.  To date the following pests have been the most significant in Ontario: none. This crop is not in a crop group.  For more information on Crop Groups, refer to the Pest section. There are few to no pest control products registered on this crop.  Always refer to product labels, and follow all directions specified on the label, before applying any pest control product.  For more information, consult an OMAFRA specialist.

Additional Notes


Ontario Research Projects Used to Create This Profile

  1. Todd, J., Thimmanagari, M., Gilroyed, B. and DeBruyn, J.  Cup Plant for Biogas Production.  OMAFRA’s Environmental Management Branch’s Kickstart funding program.  2015/2016
  1. Gansberger, M., Montgomery, L. and Liebhard, P.  (2015).  Botanical characteristics, crop management and potential of Silphium perfoliatum L. as a renewable resource for biogas production: A review.  Ind. Crops Prod. 63:362-372
  2. Stanford, G. (1990).  Silphium perfoliatum (Cup Plant) as a new forage.  Proceedings of the 12th North American Prairie Conference.  P33-38
  3. USDA NRCS.  2003.  Cup Plant Silphium perfoliatum L. var. connatum (L.) Cronq.  Plant Fact Sheet.