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Caulophyllum thalictroides

Blue Cohosh

$3.00

Packet
$3.00

Bare Root Plants
Out of Stock

Caulophyllum thalictroides (Blue Cohosh) is a beautiful woodland plant with a preference for rich moist conditions, typcial of a woodland floor. Compound leaves fill out the single leaf stalk with a lacy effect similar to Meadow Rues. New foliage can show a tint of blue or purple pigment.   The flowers are greenish yellow to greenish brown and form clusters. They are followed by berries that ripen to a deep blue.  These berries are NOT for human consumption.  Although not as poisionous as Actaea (Baneberry), Cohosh berries should never be eaten.  Leave them for the critters and for the plant to self-propagate.

*This species may be difficult and/or slow to germinate and grow to maturity.  Please note the germination code. Seed of this species is kept under refrigeration (33-38 F) in our warehouse. The days in transit to you in colder or warmer conditions won’t harm the seed, but it should be put back in refrigeration until you are ready to plant or apply pre-sowing treatment.

Live Plant Shipping Table

Spring Fall Age/Size
Dormant Bare Roots
April/May October 1 year

Caulophyllum thalictroides - Blue Cohosh

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.

4 Questions asked on Caulophyllum thalictroides

Height and width of these plants at maturity?
Hi Lora, Blue Cohosh will grow to be about 2 feet tall and 1 foot wide. In ideal conditions, Blue Cohosh does spread slowly though rhizomes.
Do you think this plant would be happy under a pin oak in full shade in my front yard. I’m worried because the oak seems to suck up all the moisture. Thanks
Hi Nicole. Blue Cohosh is often found in oak forests, so I think it could work in your yard. It does require moisture-retaining soil, though, so you may want to consider replicating a more natural environment, especially if the area under your pin oak is consistently dry. "Leave the leaves" and allow them to create a rich mulch which will store nutrients and water.
Hi, not a question, just an observation. Pic number 5 which has dark blue/brown flowers, bright yellow centers, and dark colored foliage, this picture is actually of Caulophyllum giganteum (early blue cohosh). Early Blue Cohosh is much more restricted in it's range, inhabiting primarily rich coves in the Appalachians and Allegheny plateau.
Hi William. Thank you for pointing that out! Early Blue Cohosh is a stunning plant - we have removed the photo and will be studying the two separate species.
I know that Germanation Code 'M' means that these seeds are best planted outdoors in the fall. But I missed the window--whoops! Will they still germinate if planted outside now (in mid-March) or the spring? Thank you!
Hi Andrew. This species tends to run on its own timeline, so it's hard to say. You can sow the Blue Cohosh right now (this will not harm it); the seed may germinate after experiencing the last few weeks of winter weather - or they may ride out the rest of the year and sprout next spring. Be sure to mark the area so you know where to expect them, whether it's later this spring or next year.

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
5
Seeds/Ounce
140
Germination Code
M
Life Cycle
Perennial
Sun Exposure
Partial, Shade
Soil Moisture
Medium-Wet, Medium
Height
2 feet
Bloom Time
April, May
Bloom Color
Green
Advantages
Bird Favorite: seeds, insects, fruit, nectar, nesting, perch
Deer Resistant
Highly recommended for home landscaping
USDA Zones
3-7
Catalog Code
CAU06F