Category Archives: Garden Design

thoughts on garden design

In Bloom for the Winter Solstice

A number of years back, one of the seed exchanges we belonged to listed Pycnostachys urticifolia, aka Blue Witch’s Hat. How cool, I thought, and with a common name like that, maybe it will be in fun bloom for Halloween! I clicked the “add to order” box without doing any more research.

The seed arrived and it was then that I sought the technical data:  Pycnostachys urticifolia has deep cobalt blue spires, with a noted bloom period of late fall into winter. It is not hardy here in southern New England…it winters over outdoors only in zones 9-10Blue Witches Hat grows quickly from seed and can flower the first year, with an eventual height of 4-5′. It is considered a shrub where it is hardy but its late blooming time hinders its sales potential  as a tender perennial in colder climates (which might explain why it’s seldom seen on plant lists). If you want to grow it on well you will need indoor space, either a greenhouse or a large sunroom, but what a treat it is to see its conical spires of intensely colored indigo blossoms on the shortest days of the year.

Lucky us, we have a greenhouse and now, at the Winter Solstice,  Pycnostachys provides us with lovely stems to add to a holiday bouquet of white variegated Boxwood and silvery Elk Horn Cedar cuttings.

Would you make room for this in your indoor winter space?

 

“Persistent” Perennials

Glossy evergreen European Ginger with fallen Acer foliage in early November.

I’m already missing the technicolor foliage of early November, but so it is and it’s not ALL brown out there. During this morning’s garden stroll my gaze caught sight of  various shades of green, silver, and even gold…not only from conifers but from perennials with persistent foliage.

Helleborus foetidus

It’s good to remember there are perennials that retain handsome foliage into winter. Some are considered semi-evergreen as their leaves may finally succumb once the temperatures drop into the low teens.  In order to extend their attractiveness, consider planting in a protected spot, perhaps close to the house or at the base of larger evergreens.   

Of course there are the Hellebores. There is Helleborus foetidus which begins to set bud in mild December weather, and the legendary Christmas Rose (the hybrid clones ‘Jacob’ and ‘Josef Lemper’ can begin flowering by Thanksgiving).  The many Helleborus orientalis clones retain their leaves but won’t set buds until March in our area.

Cyclamen coum

Another shade lover is Asarum europeanum commonly called European Ginger,  with its glossy dark green round foliage persists all winter. By spring it will need a cut back to welcome fresh new growth.  It doesn’t increase that quickly but is hardy in zones 4-8.

Hardy Cyclamen bloom in autumn, but their attractive foliage persists through winter. They love dry shade and actually do well at the base of trees with root competition. The two species to try are C. coum and C. hederifolium, both of which are hardy in zones 6-10.

Arum italicum ‘Pamela Harper’

A walk about the garden offered Arum italicum ‘Pamela Harper’,  other wise known as Lords and Ladies, which pops up in the October garden from summer dormancy and remains until late spring.

Rhodea japonica foliage in December.

Rhodea japonica (Japanese Sacred Lily) is grown for its evergreen lustrous dark green strap-like  foliage . We’ve had this in the garden for 20 years, a testament to its hardiness.

Very happy Epimedium ‘Domino’ foliage.

Many Epidemium are considered semi evergreen here in southern New England. ‘Domino’ , pictured above, looks especially sturdy despite last night’s temperatures in the mid 20’s.

More shade area candidates: Disporopsis pernyi is commonly referred to as Evergreen Solomons Seal.  It will form nice thicket in a shady protected bed. Of the persistent ferns, I especially like the Dryopteris erythrosora (Autumn Fern).

Sedum reflexum 'Angelina'

Sedum ruprestre ‘Angelina’

Don’t forget that Sempervivum (Hens and Chicks) and a number of Sedum species keep their foliage year round.  There’s golden leaved Sedum ruprestre ‘Angelina’ which takes on amber tones.  Another evergreen little creeper is Sedum album ‘Coral  Carpet’. Cold temperatures will bring out coral red tints to the dark green succulent leaves.

Yucca filamentosa ‘Color Guard’

Many gardeners have a disdain for Yucca, but I celebrate its ability to put up with hot sunny dry conditions, produce bayonet stalks with white lily flowers which attract hummingbirds and pollinators, and  for the their architectural form in winter.  Yucca ‘Color Guard’  boasts  yellow variegation that glows.

Euphorbia myrsinites

Other candidates for a sunny well drained spot are some of the Euphorbia (Spurge).   Euphorbia myrsinites, above, perpetuates by self sowing in poor gravelly soil.and is hardy in zones  5-9.

I do try year after year to winter over outdoors the Euphorbia x martinii hybrids such as Ascot Rainbow’ ,  not always with success. They are listed as being hardy in zone 6, but I stress this is only in a protected spot with great drainage. The ascending stems will bear showy flower bracts come early spring (flowers are formed on last year’s stems), but that is only if they do not get blasted by arctic winds.  Plants may not die, but the top growth will need to be cut back hard. The plants will break ground with new foliage growth in the spring.

There are many evergreen Euphorbia native to the Mediterranean  which are hardy to zones 7-8.  We are in zone 6B (I won’t say 7 yet).  I think with climate change upon us, we may soon be able to grow more Euphorbia species here in Southern New England.

Please share which persistent perennials you have in your garden.

Container Report Fall 2023

Phormium ‘Sundowner’ makes a great vertical feature when combined with succulents. This container had about 4-6 hours of sun, (it could have used more!) but still looks pretty fantastic. There was one casualty in the group: Echeveria ‘Afterglow’ didn’t last for long.

It is now mid October, and after a rather warm and wet September, we are being treated to a nice lingering early autumn with no frost in the forecast (fingers crossed). After so many dry summer seasons, I don’t think many gardeners here in the northeast were expecting to get so much rain this year! Foliar Fungal diseases made themselves known, but I found it interesting that our succulent combinations did so well (the key is be sure you use a succulent soil mix).

The tall cylinder urn across from the parking area gets full day sun and the succulents grew well, but the tall Euphorbia ‘Blackbird’, which added height, died sometime in early summer. The iron fiddleheads came in handy to give a little elevation.

Perhaps this rectangle terra cotta planter could have used more sun. The crassula muscosa sort of melted by September.

Echeveria ‘Lucita’ which sat in a spot receiving only morning sun, filled this Apulia bowl from Campania. This Echeveria is generous with offsets.

Bouteloua ‘Blonde Ambition’, with Lantana montevidensis (just an outstanding plant!) carried this 36″ long rectangular planter. Erigeron karvinskianus ‘Profusion’ got overwhelmed, and the annual Orlaya gave off a few white umbels and then petered out.

Think house plants for shady planters. Begonia ‘Raspberry Truffle’ is complemented by the variegated Goldfish Plant, Nematanthus ‘Golden West’ and Rhipsalis baccifera. We use mini white pumpkins to add a little fall pizazz.

The 36″ diameter Zen bowl was sited in a tough spot where it only received a couple of hours of mid afternoon sun. The Colocasia didn’t mind, nor did the Pilea microphylla (Artillery fern) and variegated Bermuda Grass, both of which overwhelmed the black leaved Geogenanthus and even the dwarf variegated Papyrus. I thought this combination of black and white variegated foliage would be more exciting….maybe it needed an urban setting and not a shady gravel area in front of an old farmhouse.

These urns are also getting more shade than sun. The yellow form of Begonia boliviensis is just not as vigorous as the more common orange form, but it still did okay. The pinky variegated Ficus is slow growing…it took all summer to grow up. Still, with Ming Fern, Oxalis spiralis aurea and Heuchera ‘Southern Comfort’ as supporting players, this combo passes the test.

The left shot was taken in late July, the right image is from a few days ago. Cordyline ‘Mocha Latte’ shot up a bit , and the Flowering Maple, Abutilon ‘Harvest Moon’ went through blossoming spurts all summer. Heuchera ‘Southern Comfort’ had better color when it received more sun earlier i the season. Oxalis spiralis ‘Aurea’ does well in so many different conditions.

Maybe it was the weather we had this year, but the Petunia ‘Mocha Latte’ was a bit of a dud by August, despite being fertilized regularly. The ensemble was relying on a constant show of white blossoms etched with chocolatey purple. One Petunia just completely died, so we tucked in a black raven statue to fill in the hole.

I realize now that the placement of these urns needs to be rethought. They are now getting much more shade than a few years ago. The combination of succulents and Elaeagnus x ebbingei would have been more impressive if it received more sun.

As I mentioned in the June report, the goal each season is to have containers that hold up throughout the season without a lot of fuss and bother. All things considered, (lots of wet and overcast weather, less time maintaining and fussing) the planters still look pretty good, and they have inspired me to do variations in 2024.

How did your containers hold up? Did you have any combos you  were especially happy with?

September Bloomers for the Shade

Aralia cordata ‘Sun King’

We’ve all learned that we should focus on foliage plants for our shade gardens, and think of any flowers as welcomed surprises. May we bring to your attention a few plants that you may want to add fora fall surprise? I would say that all appreciate partial sun…perhaps about 4 hours for a good display .

Salvia koyame

First, there is the soft yellow blooming Salvia koyame native to Japan, commonly known as Yellow Woodland Sage. It grows 2’ tall and 3’ wide, with bold gray-green leaves that are generally left undisturbed by deer, but bumbles butterflies and hummingbirds are happy to discover it.  Salvia koyame likes a well drained soil with perhaps 4 hours of sun to flower well, and is hardy in zones 5-9.

Boehmeria platanifolia

Another plant we’ve enjoyed in our shade garden for years is Boehmeria platanifolia commonly called Sycamore Nettle.  It too has bold foliage, reminiscent of Sycamore Maple with incised edges, and can attain a size of 3-4’ with equal width.  The flowers are a curious pale green-white,  and fuzzy, on drooping tassels. It is enjoyed by various bees. Plants are hardy in zones 5-9.

Japanese Shrub Mint bloom

Leucosceptrum japonicum ‘Mountain Madness’

Leucosceptrum japonicum ‘Gold angel’, with a spring Allium peeking through the foliage. Note: a good way to disguise Allium leaves.

Japanese Mountain Mint is a shrubby member of the mint family; it does not run. The form ‘Gold Angel’ with its pale lemon leaves. is more restrained in growth (2-3’) than its gold and green variegated counterpart, ‘Mountain Madness’ which quickly grows to 4-5’. Both  ‘Mountain Madness and ‘Gold Angel’ display bottle brush cream colored flowers in late September-October) and are welcomed by various bees. Generally undisturbed by deer, plants are hardy in zones 5-8.

Aralia cordata ‘Sun King’

Aralia cordata ‘Sun King’ offers a bold golden foliage alternative to Hosta that the deer bypass. In September, clusters of tiny white flowers are produced that are favored by Honeybees, which are then followed by deep purplish black seeds.  Plants can reach heights of 4-5’ in height and width, although it is generally listed to 3’, ‘Sun King’ is hardy in zones 3-9.

Plectranthus effusus longituba

Yes there is a hardy Plectranthus (through zone 6, anyway). Plectranthus effusus longituba has gone through several Genus names…It used to be called Rabdosia and also Isodon. Willowy stems adorned with long tubular soft blue lavender flowers add a softness to the partial shade garden. Plants enjoy well drained soil, and grow 2′ to 3’ tall. hardiness zones 6a-9.

a showy Toad Lily…Tricyrtis hirta ‘Tojen’

Tricyrtis ‘White Towers’

Of course there are the many Toad Lilies.  we think ‘Tojen’ gives you the best floral display, but the very graceful Tricyrtis ‘White Towers’ is a charmer. Toad Lilies like an evenly moist soil and  prefers a soil that drains well in the winter. Both are hardy in zones 4-9.

Which are your favorite late season bloomers for shady gardens?

 

 

 

A native Aster you should be growing!

Sky Blue Aster. It’s Botanical name is quite a mouthful, Symphyotrichum oolentangiense, and yes we’re fans of  its former and much more appealing name Aster azureus. This beauty is a late summer/early fall prolific bloomer with masses of sky blue-lavender flowers on stiff 2-3’ stems that rise above ovate to oblong basal foliage.  It is found throughout much of eastern North America in dry, rocky, “edge of the woodland” habitats, but will grow in most garden soils that have good drainage.  Plants spread by rhizomatous roots, so expect it to form colonies where it is happy! Like most asters, it is a favorite of many beneficial insects, bees, butterflies and moths.

Combine this aster with Bigelowia nuttallii in the foreground (Rayless goldenrod… a great undiscovered native with clusters of tiny yellow flowers held above evergreen grassy foliage clumps,) and/or any of the taller Goldenrods, such as Solidago ‘Solar Cascade’, and native grasses like Sorghastrum nutans (Indian Grass) and Schizachyrium scoparium (Little Blue Stem).

Oh yes, it likes full sun, and Symphyotrichum oolentangiense is super hardy…it grows  in zones 3-8.

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Vernonia’s time has come

A ;ate summer tapestry with Vernonia

Valued for its vibrant purple flower clusters as the gardening season wanes, Vernonia, commonly called Ironweed, is a must have for a pollinator friendly garden, and there are native forms hailing from the midwest and southern Appalachians. The common name may derive from the sturdy nature of its stems, or possibly the bronzy tan coloring of its seed heads that remain well into late autumn. The genus name honors the British botanist William Vernon, who catalogued plants on a visit Maryland in the late 1600’s.

Vernonia gigantea with tall Joe Pye Weed

We’ve had a tall form of Vernonia in our garden for a couple of decades. When I say tall, I’m talking  6-8’ tall depending on the soil moisture level that year. We purchased it as Vernonia altissima which is synonymous with Vernonia gigantea.  All too often folks shy away from tall plants, but I think that’s a mistake. Looking eye to eye, or even up at the blossoms and pollinator activity adds a dynamic  dimension. If you have very narrow planting beds, I can understand being hesitant to add such stature, but there’s a remedy…expand the size of your beds.

Vernonia lettermanii coloring in late day light

There are many Vernonia species (Kew lists over 300), and yes, some have a more restrained height. Take Vernonia lettermanii ‘Iron Butterfly’, which can fool the eye early in the season with its thread- leaf Amsonia-like foliage. It grows to 24-30” in height and becomes covered with purple flower clusters in September.

Vernonia ‘Summer Swan Song’

A number of good hybrids were recently developed at the Chicago Botanic Garden. Vernonia ‘Summer Swan Song’ is hybrid of V. lettermanii and Vernonia angustifolia ‘Plum Peachy’. It grows to about 3’ tall and wide. Vernonia x ‘Summer Surrender’ is similar in appearance but grows larger, up to 4’ tall and wide. A note about ‘Plum Peachy’, we like it for its dark tinted stems but it has proven to be slightly less hardy than its hybrid forms.  Perhaps it’s best to grow it in climate zones 6 and warmer.

Vernonia angustifolia ‘Plum Peachy’

As mentioned before, there are many other species of Vernonia, but I’ll describe one more. This year we are growing Vernonia crinita (aka V. arkansana) which is also native to the Ozark’s. It blooms a bit earlier than the others, in mid-late August, and grows 5-6’ tall. The clusters of purple asters it produces provide nectar to butterflies and bees.

Vernonia crinita

Vernonia pair well with Ornamental Grasses, Solidago, Eupatorium and Helianthus. They prefer moist soil with good winter drainage, but adapt well to a range of soil types. Vernonia are somewhat deer resistant, but watch for bunny nibbling on the new shoots when they first emerge in the spring. We treat with a rabbit repellent such as Plant Skydd.

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Container Report June 2023

Our goal each year is to create container ensembles that hold up from the beginning of the season into September or longer.  Interesting foliage is the key, with flowering plants acting as accents, rather than the other way around. Of course you know we have to do succulents…. they are so incredibly easy and look fabulous right up to frost.  Check back for our end of the season report on how well they held up.

Drum Pot 2023. Ingredients:  Cordyline ‘Mocha Latte’, Abutilon ‘Harvest Moon’, Oxalis spiralis aurea,  Heuchera ‘Southern Comfort’, Ming Fern, Begonia thurstoniiNearby Iron Urn 202. Ingredients: Begonia boliviensis yellow, Heuchera’ SouthernComfort, Oxalis spiralis aurea,  Begonia sutherlandii,  Ficus elastica variegatedDetail with iron fiddleheadsClassic Bowl on Pedestal. The foliage has filled in, but flowering is just beginning. Ingredients: Gaura ‘the Bride’, Origanum rotundifolium ‘Kent Beauty’, Cosmos ‘Chocomocha’, Stipa tenuissima, Heuchera villosa ‘Autumn Bride’, Erigeron karvinskianus ‘Profusion’2023 Brown Urn. Ingredients: Petunia’ Mocha Latte’, Heuchera ‘Obsidian’, Ming Fern, Euphorbia ‘Starblast Pink’Detail…not generally a fan of Petunias, but this proven winner selection came highly recommended by a gardening friend, and it is nice next to dark leaved foliage.Zen Bowl (36″).  Colocasia  with Cyperus  alternifolius  variegata (Dwarf Papyrus),  Pilea  microphylla (Artillery Fern), Black leaved Geogenanthus  and trailing Variegated Bermuda Grass.

Succulent Planter, potted up in early  March: Graptoveria ‘Fred Ives’, Graptosedum cv, Senecio vitalis, an Echeveria from Dick Wright, trailing Senecio The Cylinder Pot, potted up in early May:   Echeveria hybrid,  Aeonium, Portulacaria afra aurea, Graptoveria ‘Moonglow’,  Sedeveria hybrid, Euphorbia ‘Blackbird’, AsteliaUnbusy pot: a specimen Echeveria ‘Lucita’ in a blue Apulito Bowl

Simple Terracotta Rectangle, with mini Sedum adolphii ‘Shooting Stars’, Sedum rubrotinctum, Sedum borchii sport and Crassula muscosa.

Check back in the autumn to see how these fared over the summer.

 

 

Amaryllis and their Aftercare

Amaryllis ‘Wedding Dance’

So you’ve purchased or were given a gorgeous Amaryllis, and you love it. Amaryllis (Hippeastrum) are fabulous winter bloomers from the southern hemisphere. There are many species and cultivars and they can be bold and showy or delicate and ethereal. The long lasting flowers can show off for several weeks, and top size bulbs can produce multiple stems.

Amaryllis ‘Evergreen’, with smaller spidery flowers

The big question is: What should you do with your Amaryllis after the holidays to keep these plants happy and encourage them to bloom in the future?  Here are some tips.

  1. When the last flowers fade, remove the flowering stem(s). Do not let seeds form, as this will draw strength from the bulb and may inhibit flowering.
  2. Leave the green strap-like foliage on the plant to provide nourishment to the bulb and continue to give it bright light. Once warm weather arrives, you can put your plants outdoors in a spot that gets morning sun. Water only as needed. Your bulbs should be in a well drained soil mix. Do not keep soil constantly wet.

    Be sure to leave the upper third of the bulb above the soil line when you pot up.

  3. In mid-late summer (August) introduce your plants to dormancy.  They need a 2-3 month period of darkness and cool 45-50F temperatures, and during this spell, withhold water.  This is the challenging part: some of us have basements that remain dark and cool, but most of us do not.  Another option is to use your refrigerator, and this is where a spare fridge is handy.  Place the potted Amaryllis inside, minus any dead foliage.  Or, unpot your Amaryllis bulb, cut off any greenery and place in a bag with some wood shavings or dry sterile potting soil and leave to chill for at least 6-8 weeks.  In mid-late October, remove your bulbs out of their chill cycle, pot them up using a well drained soil mix and water once. Move into a sunny warm spot and do not water again until you see signs of green shooting. Sometimes it takes awhile to wake up the bulbs. Bottom heat can help.

More tips:

4. The choicest varieties need to be purchased from reputable bulb vendors in the fall.  If you want blossoms in time for the December holidays, choose bulbs that have the distinction that they were grown in the southern hemisphere, rather than having been imported from northern regions such as the Netherlands. Give yourself 6- 8 weeks lead time.  Often, these southern hemisphere grown bulbs will be labeled specifically as “Christmas Amaryllis”. Bulbs imported from Northern Europe will still bloom this winter, but they take longer to come into flower. No worries…it’s still delightful to have them burst into bloom in midwinter!

5. After the big chill, be sure to pot up in a sterile, well drained potting mix with the top third of the bulb above the soil surface.  Use a pot that’s only 2-3″ wider than your bulb(s). You could plant multiple bulbs in a large pot for a dramatic display but pack tightly, and a large container will require ample space in a sunny spot to grow on. Remember Amaryllis bulbs do not mind being pot bound. It may be 3-4 years  before it is necessary to move up into bigger pots, and/or divide.

 

 

 

 

Winter Wreaths: Thoughts and Tips

A 26″+ diameter wreath featuring selections of Elkhorn Cedar, Hinoki Cypress, Korean Arborvitae and Curly Willow.

I purposely titled this post Winter Wreaths, not  “Christmas” Wreaths. This isn’t a political statement but a simple acknowledgment that Winter Wreaths have pagan roots. At the Winter Solstice, the early Northern Europeans created wreaths to symbolize the circular rhythm of the seasons. Winter wreaths made from freshly cut greens will last well into February. There’s no need for red bows and Christmas tucks when you use beautiful plant material.

Detail of a wreath featuring Elkhorn Cedar, Cryptomeria and Hinoki Cypress.

Wreath making is a family tradition worth keeping. For years now, I’ve offered “The Day after Thanksgiving”  Wreath Making Workshop here at Avant Gardens (an alternative to mall shopping) using cuttings and branches gathered from our garden and nursery. Of course it helps that the many conifers we planted years ago have matured to give us ample material to work with (and I’m able to get in some much needed pruning at the same time!).

Many Hinoki Cypress branches in various shades of gold and green, some bearing delightful cones. (Note the leaf undersides facing up.)

So what are some of my favorite conifers to work with?  Early on I learned that Spruce and Fir, often used in commercial wreath production, did not prosper here in southern New England;  both prefer cooler summer climates. However, the many selections of Cedar do thrive: Hinoki Cypress (Chamaecyparis obtusa cv.), Japanese Cedar (Cryptomeria japonica), Korean Arborvitae (Thuja koraiensis glauca prostrata) and Elkhorn Cedar (Thujopsis dolobrata)  offer a variety of texture in shades of gold to darkest green. If you live in warm winter climates, you  have different options…I want to make a wreath using various  asparagus ferns and semi tropical evergreens.

Notice I placed some of the conifer branches so that the back side faces up...it reveals a delicate tracery, and a lovely silver color in the case of Korean Arborvitae and Elkhorn cedar.   Last year our native red cedar, Juniperus virginiana had an amazing blue berry set. Alas, this year was disappointing; there was no fruit to speak of and I worry about the poor birds who relish them. What will they feed on instead?

A wire box wreath form is covered with moss plus gathered dried fern leaves to create the base.

Our holly cultivars regularly produce a great berry set thanks to our pollinating bees. We grow ‘Blue Princess’ (Ilex x meserve cv) and  the smaller leaved Ilex x pernyi ‘Dr. Kassab’.  We have the native American Holly in the woods  at the back of our property, but they are a tad more prickly. I also use other broadleaf evergreens such as Boxwood, Inkberry, Laurel, Andromeda and even Ivy, but take note. Broadleaved evergreens desiccate quickly, especially indoors. To compensate I use a wreath base wrapped with moist sphagnum moss. Keep the moss hydrated and your holly wreath will stay fresh much longer.

Working clockwise, bunches of branches and stems bound on using 22 gauge wire. It is important to pull the wire tight as you work.

More and more people are finding the informality of foraged plant  material preferable.  Use woody plant stems with a wilder character, such as curly willow, rose hips, winterberry, or various colored osier dogwoods.  Search for moss and lichen covered twigs that may have fallen to the ground after a windstorm. Collect dried grasses and seed pods to add a variety of textures.

Let it be wild. Resist the urge to make your wreath too balanced and neat.

if you haven’t done so already, and are inspired, take a walk about your property to see what branches you can gather. Don’t hesitate to experiment; that’s what wakens your inner child and makes your wreath an original.

Note:  Please, do not harvest greens and cuttings from public spaces or private property without permission.

For winter: Arum italicum ‘Pamela Harper’

Look who’s popping up in one  of our shady corners, on cue, in mid October.  This Ellen Hornig selection of Spotted Arum (named for the wonderful gardener, Pamela Harper)  has stunning white marbled foliage edged in dark green throughout the winter, even when temperatures dip well below freezing.  It does send up a flower spathe in spring, which will be followed by orange  fruit that encases the seeds. The foliage is summer dormant, so you may forget that it’s in your garden until fall arrives when once again the new growth emerges.

Arum italicum ‘Pamela Harper’ is hardy in zones 5a-10. It prefers well drained soil in dappled shade.  Foliage height is 6-10″ tall. Not especially fast growing for us in a northern climate, but the bulbous roots produce little offsets which can be lifted and divided to spread about your garden.

Do note that all parts of this plant are poisonous.

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