PlantFiles: White Snakeroot Ageratina altissima 'Chocolate'
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Hardiness: USDA Zone 4a: to -34.4 °C (-30 °F) USDA Zone 4b: to -31.6 °C (-25 °F) USDA Zone 5a: to -28.8 °C (-20 °F) USDA Zone 5b: to -26.1 °C (-15 °F) USDA Zone 6a: to -23.3 °C (-10 °F) USDA Zone 6b: to -20.5 °C (-5 °F) USDA Zone 7a: to -17.7 °C (0 °F) USDA Zone 7b: to -14.9 °C (5 °F) USDA Zone 8a: to -12.2 °C (10 °F) USDA Zone 8b: to -9.4 °C (15 °F)
Sun Exposure: Full Sun
Danger: All parts of plant are poisonous if ingested
Bloom Color: White/Near White
Bloom Time: Mid Summer Late Summer/Early Fall
Other details: Average Water Needs; Water regularly; do not overwater This plant is attractive to bees, butterflies and/or birds
Soil pH requirements: 6.1 to 6.5 (mildly acidic)
Patent Information: Non-patented
Propagation Methods: By dividing the rootball From herbaceous stem cuttings
Seed Collecting: Bag seedheads to capture ripening seed Allow seedheads to dry on plants; remove and collect seeds Properly cleaned, seed can be successfully stored
On Dec 25, 2012, SunnyMeadow from Brevard, NC wrote:
Nancy Hanks Lincoln, Abraham Lincoln's mother, died after drinking milk from a cow that had eaten White Snakeroot. All parts of White Snakeroot are highly toxic. White Snakeroot should be grown in an area that is inaccessible to pets and children. Wear gloves when handling White Snakeroot.
On May 22, 2012, Weerobin from Saint Louis, MO (Zone 6b) wrote:
Mine arrived uninvited and I'm still pulling it.
I have a large yard and I can't pull it as fast as it's spreading. I'll admit it is refreshing to have a plant flowering in september, especially flowering nicely in the shade. But it chokes out everything else in the woodland.
In my yard, it competes with vinca, euonymus vine and honeysuckle as my worst invasives.
On Apr 7, 2012, cargarden from Goodview, MN wrote:
I only have had the plant last year & wasn't sure if you cut it down in the winter which I did, did I read right that it takes awhile for them to spring up or did I kill it.
I was supprised though that the flowers weren't larger, I planted mine in the shade.
On Sep 22, 2011, Zy from Hamilton, NJ (Zone 6b) wrote:
Have seen it growing well in any type of soil that doesn't completely dry out. On one property I've got it thriving in rich sandy soil and on my other property it's thriving in a clay loam. They can be readily transplanted from mid-spring through late autumn.
They provide good color contrast for most other plants EXCEPT those that are either very dark green (such as yews and 'Dragon Lady' hollies) or anything else with dark foliage (such as ninebark 'Diablo' and any of the maroon colored Japanese barberries). For the most striking effect, plant them adjacent to anything that has golden or chartreuse foliage.
Rather than discard all of the 'Chocolate' seedlings, I tend to save the most attractive ones for creative new uses in the landscape. Because they grow quickly to significant size, and then can be easily re-transplanted out at some later time, they are very useful for temporarily plugging spaces in the garden that are reserved for the long term growth of larger shrubs. And they can also be used en masse too. A dozen of them can quickly cover a significant area, bursting the center of an otherwise monotonous, oversized, open, sunny lawn. I created a nice quick woodland garden using a 10 sq ft patch of them surrounding a wild locust that volunteered itself near the center of my lawn. The locust seedling originated from my neighbor's ancient 90' tall giant. Locusts grow rapidly, and respond well to coppicing. Thus I maintain it as a lush 12' tall shrub by cutting it back to the ground every year. The contrast in both color and texture between the 'Chocolate' and the wild locust is striking.
In full shade its mature height is only about 60% compared to full sun, but it will still flower there just as profusely. White flowers are perfect for brightening up full shade, especially during the early autumn when few other perennials are still blooming elsewhere. It also self-seeds in far less than optimum conditions, including full shade, although not so nearly agressively as in full sun.
If you have a small garden to maintain and wish to keep just a few 'Chocolates' then it's easy to prevent them from reseeding. However, if you're always busy in a large landscape and have at least a dozen of these growing in good conditions, then it can be quite challenging to prevent an invasive spread.
They are certainly NOT a good neighbor plant in my climate zone. If you plant them anywhere within a ¼ acre parcel in zone-6, they can spread to an adjacent parcel within a year or two. Neighbors who are already negligent about controlling various other tall weeds may have even less success controlling this invader. So invading back from your neighbors' parcels it could possibly become a persistent weed problem for you, years after you changed you mind and "eradicated" it.
Fortunately though it doesn't have a tap root, lending its shallow clumpy root system easy to hand-pull when the soil is moist.
Nine years ago I purchased (3) 'Chocolates' from a garden center in Vermont. I now have approx 100 growing at my two homes and I'd have many, many thousands if I didn't weed out at least a thousand of them over the years.
I've observed that many of its seedlings are a good likeness of its true cultivar, even a few generations later. However, there will always be a large proportion of the seedlings that revert to its boring albeit native general species, which has plain green stems and lighter green leaves. I've seen large patches of that less interesting "ancestor" growing natively along shaded banks of the Delaware R. at Bordentown, NJ.
On Jun 14, 2011, AmandaEsq from Greensboro, NC (Zone 7b) wrote:
Love it - chocolate eupatorium has shiny, deep purple stems with chocolate leaves and delicate white fuzzy blooms in late summer/fall. It stands 4’ tall and 3' wide. Bees and butterflies love it too.
I have read sources which suggest it can take full sun, but I wouldn't recommend it!!! It likes moist, well-drained soil. I recommend morning sun. If you're in a cooler climate, it will probably take more sun than it does here in sunny NC.
I collected the seed in MA and grew it here from seed in 2009. I set 5 plants in a perennial bed then, and all 5 survive here in zone 7b. I planted them under a large pecan tree, but the sun doesn't pass over until after high noon. The plants suffer wilt at high noon but recover well in the afternoon shade. I have mulched them heavily which may have kept them from re-seeding. I have never seen a volunteer. I expect to move these plants to a shadier location this season.
On May 1, 2010, SalviaFanatic5 from Dover, DE wrote:
I really haven't had any problems with this one. Its a slow perennial to get going. I haven't had any problems with it being invasive. It does tend to fall over once it's in full bloom. I love it, though. It's a bee magnet. If you're a fan of bees, this is the plant for you.
On Sep 16, 2008, GardenKrol from Clarksburg, MD wrote:
I was thrilled this to find this lovely plant blooming in scattered shady locations around our 15 acres of wooded hill and wetland. I was able to identify it using the CT Botannical Society plant list. It seems to be most robust in the moister areas with good leaf litter, but I have not observed it in the wetland. I'll report back if I do find it there. I have not noticed it on the property in previous years, but I'm just becoming really aware of the wonderful wildflowers in our area. I'd love to have it my shade garden but I'm loathe to disturb any of the native wildflowers; I'll try to collect some seeds. My plant is obviously NOT the cultivar 'Chocolate', but I thought folks would be interested to hear about the wild parent plant.
On Apr 27, 2008, artemiss from Toledo, OH (Zone 5b) wrote:
I planted this plant in a semi-shaded/morning sun bed in the front and it seemed to thrive. I LOVE the dark foliage and the contrasting late-season white flowers.
However, like another poster, mine didn't survive the winter. Someone else mentioned that it seems to prefer wetter areas, so I might try it in a different spot this year.
Apparently this is a VERY late one to sprout, as of today I have a little nub coming back. So I would advise anyone thinking this one is a goner to give it some time.
On Jun 17, 2007, daryl from vernon, BC (Zone 6a) wrote:
A little known species related to the tall Joe pye weed,native to large areas of eastern north america.This new selection has dark bronzy-brown leaves in the spring turning green when the autumn display of fuzzy white flower clusters appear.Excellent for foliage contasts in the border.Attractive to butterflies.Tolerates shade.
On Jun 18, 2006, ifonly from Brookfield, CT wrote:
I have NO clue what caused me to think this plant likes shade, but it's growing under a peegee hydrangea. I do like its late white flowers against its dark leaves - very pretty with dark-leaved cimicifuga and the green-leaved Joe Pye weed in front of my white wood birdhouse with verdigris copper roof. Terrific late season grouping. Let's see what happens when I move it into more sun.
On Jun 7, 2006, sterhill from Atlanta, GA (Zone 7b) wrote:
I've not had the invasive problems with this plant but I also mulch well. I have mine in heavy shade as in the sun it wilted and fell over. I had to move it twice to get it out of any afternoon sun. Pretty contrast plant.
On Jun 6, 2006, Erynne from Hillsburgh, ON (Zone 5a) wrote:
I have two of these plants; one in moist shade with 2 hrs of filtered sun in the evening and the other in a drier partially-shaded site. The one in moist shade is doing better hands down. I haven't experienced the self-seeding issues as yet but I am a mulch-aholic so this could be why I haven't found any seedlings. I find the growth habit of this plant in my garden to be very tidy at this stage (2nd year plant) and the foliage is very attractive, especially when companion-planted with dark heuchera. Personally, I don't grow it for the flowers and may cut them off when they appear.
September 2006.....go figure, I found a seedling afterall. It's about 8 inches tall now and I'm not sure how I managed to miss it being there. I love the foliage on this plant but you can be certain I'll be snippety-snipping off those buds so they don't get to flower! Another thing I've noticed on my Eupatorium rugosum.....leaf miners! I removed the affected leaves and so far they haven't come back (crossing fingers).
On May 15, 2006, victorgardener from Lower Hudson Valley , NY (Zone 6b) wrote:
Could not agree more strenuously with the other negative. The first four or so seasons were great. Nice foliage and pretty late-season white blooms. Then, the horror began and has not stopped. It is one of the WORST re-seeders out there. It will take me years to get rid of it. Don't do it - there are other plants with similar characteristics without the horror.
On Oct 13, 2005, CaptMicha from Brookeville, MD (Zone 7a) wrote:
I had no idea that this was the plant I had growing in my butterfly garden but I just IDed.
My plant was growing in the shade of my common milkweed and butterfly bush and it's COVERED in flowers. I appreciate this plant's ability to produce flowers so late in the season b/c it provides an important nectar source for fall migrating monarchs.
I plan on digging up my sole plant and re-planting where it will get complete sun.
This plant is beautiful, but is growing wild in my area. It appeared in my border this year where I neglected to pull it due to it's purple leaves. I was astounded at the beautiful tiny white airy flowers. I have another growing in a more negelected part of my property that is in shade and had green leaves.
On Sep 27, 2005, levilyla from Baltimore, MD (Zone 7a) wrote:
This plant reseeds so much that you do not want it anywhere near your perennial border. It may be pretty off in a wild area in early fall, but somehow the seeds seem to arrive back in the border. Everytime I see one I pull and throw away.
On Aug 14, 2005, janesdtr from Pittsburgh, PA (Zone 5b) wrote:
Lovely foliage and vigorous grower in full sun area. I've found the foliage loses the chocolage color and vigor in part-shade/shade. Looks especially pretty when placed near a purple or white buddeleia.
One warning - it self-sows prodigiously! I pull hundreds of seedlings every year.
I purchased this plant in April 2002 while living in Dundalk, Maryland. At that time I had only a cement backyard and gardened only in containers. Five months later in September we moved to Cecil County, Maryland (USDA Zone 6b/7a.)
All 250 pots of trees, shrubs, perennials, and ground covers were moved to our new - and COLDER - residence.
Today I checked all pots to find that my 'Chocolate' White Snakeroot is doing extremelly well.
On Jan 26, 2003, Terry from Murfreesboro, TN (Zone 7a) wrote:
Purchased this plant two seasons ago; so far, it has been very well behaved in a semi-shade bed; the foliage has remained dark, which contrasts nicely with the flowers.
This plant has been said to grow in the following regions:
, San Francisco, California Brookfield, Connecticut Rodney Village, Delaware Atlanta, Georgia Chicago, Illinois Glendale Heights, Illinois Mount Prospect, Illinois Palmyra, Illinois Rockford, Illinois Washington, Illinois Balltown, Iowa Davenport, Iowa Lawrence, Kansas Baltimore, Maryland (2 reports) Brookeville, Maryland Conowingo, Maryland Dundalk, Maryland Green Valley, Maryland Lexington, Massachusetts Rehoboth, Massachusetts Wakefield, Massachusetts Bay City, Michigan Charlevoix, Michigan Ludington, Michigan Goodview, Minnesota Grant, Minnesota Gladstone, Missouri Independence, Missouri Hanover, New Hampshire Folsom, New Jersey New Milford, New Jersey White Horse, New Jersey Boone, North Carolina Brevard, North Carolina Elizabeth City, North Carolina Greensboro, North Carolina Blaine, Ohio Dayton, Ohio Fruit Hill, Ohio Toledo, Ohio Williamsburg, Ohio Oklahoma City, Oklahoma Ambler, Pennsylvania Mercer, Pennsylvania Morrisville, Pennsylvania Pittsburgh, Pennsylvania North Augusta, South Carolina Murfreesboro, Tennessee Lexington, Virginia Newport News, Virginia Clinton, Washington East Port Orchard, Washington Fircrest, Washington Kalama, Washington Lake Goodwin, Washington Olympia, Washington Shorewood Hills, Wisconsin