SEED ORDERS OVER $100 SHIP FREE!
Silphium perfoliatum

Cup Plant

$3.00 - $225.00

Packet
$2.00 $3.00
1/8 oz.
$4.00
1/4 oz.
$6.00
1/2 oz.
$9.75
1 oz.
$15.00
1 lb.
$225.00

Bare Root Plants
Out of Stock

3 Pack
Out of Stock
Tray of 50
Out of Stock

Standing tall at around six feet (more in wetter soils, less in drier soils), Cup Plant's yellow blossoms can be seen starting in July when the butterflies visit them, and then later when the birds begin to feed on its seeds. Throughout the growing season, the water held in the leaf cups attract birds and other critters looking for a drink.  Cup Plant establishes well in average garden soil or in heavier, wetter soils. It is easy to start from seed by fall planting outdoors, or, if planted in spring, a period of 60 days of moist, cold stratification is recommended prior to sowing.

A vigorous plant throughout its range, this species can be invasive when planted outside of its historic regions.  Check the RANGE MAP tab to see if this species is historically native to your state.  If your state shows blue-green coloring instead of lime green, this species is best not planted there. It is listed as noxious (pink) in NY and CT. Even within its range, it would not be a good choice for small landscapes as it could overwhelm smaller plants. 

As the specific epithet "perfoliatum" suggests, each pair of leaves clasp the stem, making it look like the stem has pierced through them. The leaves themselves form a small basin that allows rain water to collect in tiny pools around the stem, hence the cup comparison. It has been suggested that this may be a primitive form of carnivorous behavior in the plant world. Certainly, one can see how this would set the stage for more specialization in that niche but, at least currently there has been no evidence of the plant gaining any nutritional benefit from the insects that may have drowned in there. It is more likely that this anatomical feature is a way of deterring potential flower predators from crawling up the stem in search of a meal. Indeed, for insects, these pools can form a considerable barrier against vertical movement. 

Live Plant Shipping Table

Spring Fall Age/Size
Dormant Bare Roots April/May October
Potted 3-Packs May/June September 2.5" wide x 3.5" deep pots
Potted Trays of 50 May/June N/A 2" wide x 5" deep plugs

Silphium perfoliatum - Cup Plant

Map Key

Present in state
Present but introduced in county
Present and native in county; not rare
Not present in state
Present and native in county; rare
Species extirpated (historic)
State or county listed as noxious
Present in state; exotic

This map shows the native and introduced (adventive) range of this species. Given appropriate habitat and climate, native plants can be grown outside their range.

7 Questions asked on Silphium perfoliatum

I live in Maryland, which is brown on your range map. Should I not grow the cup plant here?
The maps show the historical range (native and adventive) of a native species. Adventive means it was introduced by humans but is growing successfully; and in the case of Cup Plant on the East Coast, it is very aggressive. We don't experience that here in the Midwest. Because of this, I would only suggest planting it after talking to a Professional in your state. Yes, we are surprised Cup Plant was never documented in MD. Perhaps just a lack of Botanists there at the time :)
hi, how long does a Silphium plant take to bloom from seed? 1st year or 2nd year? thx!
Hi Sue. Most of the Silphium species, including this Cup Plant, germinate readily and grow fairly fast. But, being a long-lived perennial plant, I wouldn't expect a bloom in the 1st year; 2nd year or 3rd year is more likely.
Hi, I have some cup plants in my garden. I love them. Do I need to do any pruning? And if so, do I prune in the fall or the spring? I live in southeastern Wisconsin. Thank you!
No, Cup Plant will come back from the ground up each year. We advocate leaving garden plants fall and winter for food and cover for wildlife. Cup Plant especially is full of nutritious seeds to sustain the birds that stay the winter with us. The stem is also hollow and sturdy and many beneficial insects will overwinter in the stems. When you do perform your spring clean-up, consider just piling the dead Cup Plant stalks to the side until the insects have emerged.
Hi, I planted a cup plant a couple years ago and last summer I had three new plants up. This spring looks like a lot more. I was going to divide it up and give some of the new ones to friends, is there a preferred method to do that?
Thanks for writing, Meaghan. Cup Plant is a robust grower and prolific self-seeder. Transplanting any plant always involves some shock to the roots, so we recommend digging only when the plant is dormant, either in spring before it starts growing or in fall after the growing season has ended. Those are the two times we dig dormant plants for sale as bare roots. As you can see in the root photo reached through the following website link, this species develops deep roots, so you will need to dig deeply and carefully to preserve them.
I live in Bucks County, PA, outside Philadelphia. This is showing 'lime green' on your range map, which I think means that it is native to this area and it is fine to plant it (maybe I'm color blind, but I can't figure out what you mean by blue green, I see dark green for areas not to plant it in). I am thinking of this plant as a good one to combat nasty invasives, such as knotweed. Basically attack the knotweed, than plant this on the same ground, and let it overwhelm the knotweed. Is this a sound idea?
Hi Erich. Yes, it may be hard to see on some screens but the blue green means "present in county, but introduced" by human intervention. Eastern PA counties in lime green and Northern NJ counties in blue green, if you can see the difference in color that way?

Cup Plant is very tough and, yes, I think it could compete with Japanese Knotweed, although you may need more aggressive methods to eliminate such an invasive plant as Knotweed. You'll note that some areas in the Northeast actually classify native Cup Plant as a noxious weed (pink - as in CT). That is not our experience here in the Midwest. It thrives where planted but does not spread in an overly aggressive manner.

I winter sowed cup plant seeds and I see that they are germinating! I am not expecting blossoms this summer, but I'm hoping they will get big enough to contribute to what I hope to be an obvious row of plants to mark our property line this summer...in ideal conditions, what can I expect this first season? Thank you!
HI Erin! Great to hear of your successful germination. If this property line is free of competition from other plants, and gets plenty of sun and ideal moisture, you will get good-sized juvenile plants this year. Maybe 1/2 their mature size of 6'? I would bet you get blooms next year! Cup Plant makes a terrific living fence!
Is there a native alternative to cup plant for those of us in the northeast? I really like its flowers that attract pollinators, its height, and its hollow stems that native bees nest in. However, I live in MA where cup plant is invasive so I want to find a plant native to the northeast with those qualities.
Hi Bob. I understand! Cup Plant is so great for pollinators, and lucky for us in the Midwest, it does not behave quite as aggressively. I could suggest the other popular Silphium species - Compass Plant, Prairie Dock or Rosin Weed, but they are not native to your area. They should grow in the East, it just depends if you want your planting to be strictly native to your area. We have RANGE MAPS on each plant webpage; only Whorled Rosin Weed is native to some East Coast states.

Seed

Growing your own plants from seed is the most economical way to add natives to your home. Before you get started, one of the most important things to know about the seeds of wild plants is that many have built-in dormancy mechanisms that prevent the seed from germinating. In nature, this prevents a population of plants from germinating all at once, before killing frosts, or in times of drought. To propagate native plants, a gardener must break this dormancy before seed will grow.

Each species is different, so be sure to check the GERMINATION CODE listed on the website, in the catalog, or on your seed packet. Then, follow the GERMINATION INSTRUCTIONS prior to planting. Some species don't need any pre-treatment to germinate, but some species have dormancy mechanisms that must be broken before the seed will germinate. Some dormancy can be broken in a few minutes, but some species take months or even years.

Seed dormancy can be broken artificially by prolonged refrigeration of damp seed in the process of cold/moist STRATIFICATION. A less complicated approach is to let nature handle the stratifying through a dormant seeding, sowing seeds on the surface of a weed-free site in late fall or winter. Tucked safely beneath the snow, seeds will be conditioned by weathering to make germination possible in subsequent growing seasons.

To learn more, read our BLOG: How to Germinate Native Seeds

Dormant Bare Root Plants

We dig plants when they are dormant from our outdoor beds and ship them April-May and October. Some species go dormant in the summer and we can ship them July/August. We are among the few still employing this production method, which is labor intensive but plant-friendly. They arrive to you dormant, with little to no top-growth (bare-root), packed in peat moss. They should be planted as soon as possible. Unlike greenhouse-grown plants, bare-root plants can be planted during cold weather or anytime the soil is not frozen. A root photo is included with each species to illustrate the optimal depth and orientation. Planting instructions/care are also included with each order.

Download: Installing Your Bare-Root Plants

Potted Plants

3-packs and trays of 32, 38, or 50 plants leave our Midwest greenhouses based on species readiness (being well-rooted for transit) and order date; Spring shipping is typically early May through June, and Fall shipping is mid-August through September. Potted 3-packs and trays of 38 plugs are started from seed in the winter so are typically 3-4 months old when they ship. Trays of 32/50 plugs are usually overwintered so are 1 year old. Plant tray cells are approximately 2” wide x 5” deep in the trays of 38 and 50, and 2.5" wide x 3.5" deep in the 3-packs and trays of 32; ideal for deep-rooted natives. Full-color tags and planting & care instructions are included with each order.

Download: Planting and Care of Potted Plants

*PLEASE NOTE: we are a mail order nursery and have no retail facilities, but you may pick up your order if prior arrangements are made. Pick up orders are subject to **MN Sales Tax.

US Shipping & Handling Charges

SEED $100.00 and under: $5.00
Retail SEED orders over $100.00 ship free!

Custom seed mixes or discounted seed sales over $100, add 5% of the total seed cost
(for orders over $1,000 a package signature may be required)

BARE ROOT and POTTED PLANTS $50.00 and under: $9.00
over $50.00: 18% of the total plant cost. (For orders over $1,000 a package signature may be required.)

TOOLS and BOOKS have the shipping fee included in the cost of the product (within the contiguous US).

**We are required to collect state sales tax in certain states. Your state's eligibility and % will be calculated at checkout. MN State Sales Tax of 7.375% is applied for orders picked up at our MN location. Shipping & handling charges are also subject to the sales tax.

Shipping Season

SEED, TOOLS and BOOKS are sent year-round. Most orders ship within 1-3 business days.

BARE ROOT PLANTS are shipped during optimal transplanting time: Spring (April-May) and Fall (Oct). Some ephemeral species are also available for summer shipping. Since our plants are field-grown, Nature sets the schedule each year as to when our season will begin and end. We fill all orders, on a first-come, first-serve basis, to the best of our ability depending on weather conditions beyond our control.

POTTED PLANTS (Trays of 32/38/50 plugs and 3-packs) typically begin shipping early May and go into June; shipping time is heavily dependent on all the species in your order being well-rooted. If winter-spring greenhouse growing conditions are favorable and all species are well-rooted at once, then we ship by order date (first come, first serve). We are a Midwest greenhouse, and due to the challenges of getting all the species in the Mix & Match and Pre-Designed Garden Kits transit-ready at the same time, we typically can't ship before early May. Earlier shipment requests will be considered on a case-by-case basis.

*We are unable to ship PLANTS (bare root or potted) outside the contiguous US or to CALIFORNIA due to regulations.

Delivery

We ship using USPS, UPS and Spee Dee. UPS and Spee Dee are often used for expediting plant orders; they will not deliver to Post Office Box numbers, so please also include your street address if ordering plants. We send tracking numbers to your email address so please include it when you order.

FOR MORE DETAILED SHIPPING INFORMATION, INCLUDING CANADA SHIPPING RATES (SEED ONLY), PLEASE SEE 'SHIPPING' AT THE FOOTER OF THIS WEBSITE.

Details

Seeds/Packet
75
Seeds/Ounce
1,250
Germination Code
C(60)
Life Cycle
Perennial
Sun Exposure
Full, Partial
Soil Moisture
Medium-Wet, Medium
Height
6 feet
Bloom Time
July, August, September
Bloom Color
Yellow
Advantages
Pollinator Favorite: butterflies, moths, bees, wasps, beetles
Bird Favorite: seeds, insects, fruit, nectar, nesting, perch
Deer Resistant
USDA Zones
4-8
Plant Spacing
2-4'
Catalog Code
SIL56F