Plant of the Month (June) : California buckwheat - Eriogonum fasciculatum

California buckwheat (Eriogonum fasciculatum) in foreground

 

The buckwheats (genus Eriogonum) are among the most important summer-flowering plants in S. California gardens.  In a typical year, the period from May through October is replete with their beauty.  Beginning with the California, Conejo and Red buckwheats, transitioning into the giant St. Catherine’s lace and ending with the Coastal/dune and Ashy-leaf buckwheats, the Eriogonums span the seasons with floral, seed and foliage color.   Our hot dry winter and spring have confused many plants this year.  But true to form, California buckwheat is a standout in our June floral display.

California buckwheat has a wide geographic distribution compared to other local  buckwheats.  It grows from California, Utah and Arizona in the north to northern Mexico and Baja California, Mexico, in the south.  There are at least four recognized varieties.  Two of them (varieties fasciculatum and foliolosum) are native to western Los Angeles County, including the Palos Verdes peninsula and the lowland areas of the old El Segundo dunes (coastal area from El Segundo south to the Palos Verdes peninsula).   

The species grows in a number of plant communities including Chaparral, Coastal Scrub, Coastal Areas, Desert Chaparral,   Oak and other Woodlands and Grasslands.  Locally it is found in Coastal Sage Scrub, Coastal Shrubland and Back Dune/Coastal Prairie communities.   Variety fasciculatum grows primarily below 1200 ft. elevation, while variety foliolosum will sometimes be found as high as 5000 ft. elevation.   Both grow in hot, dry locations with well-drained soils, often on open slopes, mesas and bluffs.   It’s not surprising that California buckwheat is a tough, hardy survivor.

Eriogonum fasciculatum growth habit - Rancho Santa Ana Botanic Garden
Claremont, CA

Like many of our local perennial buckwheats, Eriogonum fasciculatum is a mounded sub-shrub with a woody base and more herbaceous new growth.  Variety fasciculatum, which is typical of coastal sub-shrubs, is more likely to be low-growing – even decumbent (lying on the ground) - particularly along the coast.  Variety foliolosum is more upright and mounded.  Both have numerous, rather thin branches and dense growth.  Mature plants are 3-5 ft tall and wide, but may spread to 6-7+ feet wide in the garden.  Plants have a moderate growth rate and are among the longer-lived native shrubs. 

Leaves, California buckwheat (Eriogonum fasciculatum)

The leaves of Eriogonum fasciculatum give California buckwheat its name.  They are clustered in dense bundles (fascicles) along the stems.  As is common for the genus, California buckwheat’s leaves roll under in the dry months.  In this species, the leaves become very tightly rolled, giving them an almost needle-like appearance.   The leaves are small (3/4 inch or less), dark- to gray-green above, lighter and hairy beneath.  Plants are evergreen except in the severest of droughts.

 

Flowers, California buckwheat: Madrona Marsh Native Plant Gardens,
 Torrance CA

Native buckwheats are amongst the prettiest of flowering plants and California buckwheat is a real prize winner.  The plants are massed with flowers from late spring through mid-summer.  While individual flowers are small (see below), they form dense terminal clusters that can nearly cover the foliage.  California buckwheat’s flowers range from white to pale pink.  The flowers are in parts of six and the stamens (pollen producing organs) extend beyond the perianth, giving flower clusters a fuzzy appearance. 

 

Flowers: California buckwheat (Eriogonum fasciculatum)

California buckwheat is an important pollinator plant.  On a warm summer day, plants are alive with insects ranging in size from butterflies to tiny native bees.  Buckwheats are probably our best all-round summer pollinator plants.  They attract the entire range of pollinator insects: butterflies, European honey bees (honey is delicious!), native bees of all sizes, pollinator flies, beetles and many others.  Plant a native buckwheat if you’re concerned about the health and welfare of our pollinators.

If you’ve only space for one native habitat plant, let it be a buckwheat.  Native buckwheats are long-blooming, supplying thousands of flowers at a time.  The flowers produce high quality nectar and pollen, so they attract both pollen- and nectar-seeking insects.  Many of them are larval (caterpillar) food sources for native butterflies.  For example, California buckwheat provides larval food for Mormon Metalmark, Bernardino Blue and Bramble, Common and Avalon Hairstreak butterflies.  Rabbits and some birds (quails) eat the flowers and foliage. Birds and small creatures take cover under the dense, shady foliage.
 

 

California buckwheat flowers, seeds

As if that’s not enough, the Buckwheats also produce small, tasty seeds.  On a fall day, it’s not uncommon to spot a group of seed-eating birds on/near a garden buckwheat, busily partaking of the feast.  Among those you may encounter are the finches, Dark-eyed juncos and Brown towhees.  Many gardeners let their buckwheats go to seed simply to attract the seed-eaters.  But that’s not the only reason to hold back on deadheading your buckwheats.
 

 

California buckwheat through the seasons. Plant is the shrub just behind
 the right side of the arbor

Buckwheats help us celebrate the cycle of seasons.  Their fresh new growth indicates the height of the growth season; their flowers the end of growth and beginning of the dry season.  And their dried flowers and seeds – with their lovely rust and brown tones - signal the end of the dry season.   The color palette of the buckwheats is an inspiration to artists and garden designers alike.  But the yearly cycle of the buckwheats – unchanging, unhurried and rhythmic – connects us to the earth and our S. California natural heritage.  Priceless!

California buckwheat prefers full sun but will take some afternoon shade.  While it likes a well-drained soil, it can be grown in any local soil from sandy to clay.  If you have a clay soil, consider planting buckwheats on a small berm and be careful not to over-water in summer.  

Eriogonum fasciculatum and most other locally native buckwheats do well in alkali soils, which don’t bother them in the least.  If you use an organic mulch, go lightly.  We recommend starting with a 2” layer at planting time, then letting the mulch degrade naturally, without replenishment.  Once this buckwheat gets going, you won’t need mulch to control the weeds!  For more on mulches see: Understanding Mulches - http://mother-natures-backyard.blogspot.com/2012/07/understanding-mulches_23.html.

Watering California buckwheat requires an understanding of the plant’s survival mechanisms.  This plant has a long taproot, allowing it to access deeper soil water.  It also has shallower, fibrous roots.  It needs good winter/spring water.  In fact, in a dry year like this, we watered our buckwheats deeply about once a month to supplement the rainfall.  The dry season is a bit more challenging.  Some buckwheats, for example Eriogonum parvifolium, are very sensitive and do best with very occasional or no summer water.  California buckwheat – and particularly the cultivars – are more forgiving.   They look good with occasional summer water – perhaps several times in a summer in western Southern California.

Buckwheats are fairly carefree garden plants.  They have few pests and diseases and are generally hardy plants.  Local gardeners cut this species back in late fall to promote plant health.   This cutting back should begin in the first years of life or the plants will become too woody.  Woody old plants should be replaced – with a pledge to prune the replacement properly and regularly.  Cut plants back to 4-6 inches above the woody part of the stem.  That’s about all it takes.

Eriogonum fasciculatum in garden.  It is the shrub with masses of
pale pink blooms behind the bright pink Red buckwheat

California buckwheat is a staple in habitat gardens.  It is often used mid-bed with smaller plants in front of it and can be used as a mid-sized ground cover.  It works well on dry slopes and in areas that are difficult to water.  It complements native Salvias in foliage and flowering.  California buckwheat is planted in rock gardens and can easily be included in gardens featuring water-wise Mediterranean herbs like Rosemary and Lavender.  Once in place, try not to move it – the long taproot makes it difficult to move successfully.

One word of caution: this plant is best planted within its natural range.  It has escaped cultivation and is becoming a weedy non-native  in some areas of Northern California, Oregon, Arizona and Texas.  Be a responsible gardener, particularly if you live near wild areas; plant the species and varieties that are native to your area.

 

Eriogonum fasciculatum 'Dana point'

There are several cultivars that are widely available.  ‘Dana Point’ is a lovely mounded cultivar that does very well in local gardens.  It grows to about 2 1/w ft. tall and spreads to 5+ feet wide.  We have this cultivar in Mother Nature’s Backyard.  It draws raves every year.

Cultivar 'Warriner Lytle' is lower growing – usually less than 2 feet – with dark green leaves and somewhat resembling a prostrate Rosemary.  It makes a good groundcover and would do well on hot slopes.   ‘Theodore Payne’ buckwheat is even shorter (1 ft.) and is also recommended as a ground cover.

Eriogonum fasciculatum 'Theodore Payne'

California buckwheat is used medicinally where ever it grows.  Native Californians and other Native Peoples use it primarily to treat headaches, stomach problems, diarrhea and wounds.  Both the leaves and roots are used, fresh and dried.   For colds, coughs and sore throats and pre-menstrual bloating a mild tea is prepared.  A stronger decoction from roots was traditionally used for diarrhea, stomach troubles and to ‘clean the system’.  A strong tea from the leaves is reported to cure headaches and a decoction from young flowers is used as an eyewash.  A poultice made from dried roots or fresh leaves and flowers was formerly applied to wounds.  For medicinal uses, older established plants are reported to be more efficacious. The small seeds and young shoots are edible.  The leaves were traditionally used to line granaries to keep acorns dry.

In summary, California buckwheat is an extremely useful shrub.  It is excellent for habitat, requires little care and is a great addition to water-wise gardens where ever it grows naturally.

 

 

For a gardening information sheet see: http://www.slideshare.net/cvadheim/gardening-sheet-eriogonum-fasciculatum

For more pictures of this plant see: http://www.slideshare.net/cvadheim/eriogonum-fasciculatum-web-show

 

 

We welcome your comments (below).  You can also send your questions to: mothernaturesbackyard10@gmail.com

 

Plant of the Month (August) : St. Catherine’s Lace / Giant Buckwheat - Eriogonum giganteum

Giant Buckwheat (Eriogonum giganteum) in Mother Nature's Backyard

Some native plants look good all year long.  Local gardeners depend on them as the seasons change from rainy spring to dry fall.  One such garden stalwart is a large native Buckwheat commonly called St. Catherine’s Lace or Giant Buckwheat.  Eriogonum giganteum is at the peak of bloom now in Mother Nature’s Backyard.

St. Catherine’s Lace is one of several Buckwheats included in our garden.  Southern  California is blessed with a selection of wonderful native Buckwheat species.  They do well in local gardens and are used extensively; they also provide important habitat for insects, birds and other creatures.  For more on local buckwheat species see ‘Plant of the Month’ for July and November, 2012.

Eriogonum giganteum (Giant Buckwheat/
St. Catherine's Lace) provides a spot of fall color

Giant Buckwheat hails from the Channel Islands just off the coast of Southern California.   There are three varieties (natural variants) of Eriogonum giganteum, each endemic to a different island: var. compacta grows on Santa Barbara Island,  var. formosum on San Clemente Island and var. giganteum (the one most used in local gardens) is endemic to Santa Catalina Island.   All variants are uncommon in the wild and species of conservation concern.  Their rarity – as well as their propensity to interbreed with other native Buckwheats like Eriogonum arborescens (Santa Cruz Island Buckwheat), Ashy-leaf Buckwheat (Eriogonum cinereum) and Eriogonum fasciculatum (California Buckwheat) – has prompted the California Native Plant Society to place all three varieties in its Rare and Endangered Plants Inventory.

All forms of Giant Buckwheat grow on dry slopes and rocky cliffs in the chaparral and coastal sage scrub plant communities.   They are hardy plants that survive dry summers, nutrient poor soils and blustery coastal winds.   They also have the flexibility to thrive under water-wise garden conditions, particularly if left to their own devices.

 

St. Catherine’s Lace is one of the showiest local Buckwheats.   Its foliage is gray-green to silvery white;  the foliage is most silvery under dry conditions.   The leaves are much larger than most Buckwheats and provide nice contrast to plants with either green or silver foliage (see photo below).   In most gardens, occasional water keeps St. Catherine’s Lace evergreen.  In the wilds – or with no summer water – the plants are semi-deciduous (lose some leaves).



Flowers of Eriogonum giganteum

Giant Buckwheat produces loads of small Buckwheat flowers (see photo above). The flowering season is late spring to summer: we’ve seen plants start blooming as early as May and as late as August.  The flowers are densely packed in large, rather flat clusters.   The cluster’s texture suggests a heavily embroidered lace, hence the common name ‘St. Catherine’s Lace’.  The young flowers are pink, turning more orange as the season progresses.  The flowers are so numerous – and the clusters so large – that this plant is a show-stopper in many gardens (see photo below). 

Like all Buckwheats,  St. Catherine’s Lace is a great habitat plant.  The many small flowers, with their abundant nectar, attract a wide range of native insect pollinators including native bees, pollinator flies, wasps and butterflies.  A blooming St. Catherine’s Lace will be alive with insects on a warm summer day. Among the butterflies will be the smaller skippers, acmon blues and gray hairstreaks plus a few larger butterflies. In the fall, the red-brown seeds are a treat for migratory seed-eating birds like finches.  What fun to watch on a warm fall day!  Mature plants also shelter birds and lizards all year long.

St. Catherine’s Lace is the largest of our S. California native Buckwheats, attaining a mature garden size of 5-8 ft. tall and wide.  Gardeners should carefully note the size;  this is a large plant that needs sufficient space to grow.   Choose one of the smaller Buckwheat species if space is limited.

 

St. Catherine's Lace after fall pruning

Like most local Buckwheats, St. Catherine’s Lace is a sub-shrub, with woody lower stems and herbaceous new growth.    The overall shape of mature plants is rounded and dramatic, with several main stems.  In fact, this species is best if left to develop its natural form, with only a little shaping.   We prefer to leave the orange-brown flower clusters in place until the birds have eaten most of the seeds.  The spent flowers provide a nice touch of fall color in the autumn garden.  Prune off the dead flowering stalks in late fall for a neater appearance (see above).  Often this is all the pruning that’s required.

Giant Buckwheat is surprisingly tolerant of garden conditions if not coddled too much. It does well near the coast as well as in hot inland gardens.  While its native soils are rocky and well-drained, it thrives even in clay (with judicious summer water) and requires no fertilizer.  It does well in full sun or part shade.  In fact it is quite easy and adaptable, even growing under eucalyptus trees with their thick natural mulch (see above).    Plants require only occasional summer water to look attractive.  Let the soils dry out between waterings, then water deeply.  In clay soils we usually water once a month or less in summer, depending on temperature and wind.

Eriogogum giganteum paired with 'Winifred Gilman' Salvia

St. Catherine’s Lace looks beautiful paired with Salvias (see above), other Buckwheats, white-foliage plants like Catalina Silverlace (Constancea (Eriophyllum) nevinii) and evergreen shrubs like Coyote Bush (Baccharis pilularis) and Ceanothus. It does well on slopes and can even be grown in large containers.  Some gardeners use it for an informal hedge.  Its dried flower clusters make a dramatic addition to floral arrangements. And Native Californians used St. Catherine’s Lace for medicines to relieve headaches and stomach aches.

As a final note, we return to the observation that native Buckwheats are notorious in their ability to hybridize.  The propensity of Buckwheats to hybridize (produce crosses between two species) is both good and bad.   Hybridization can be advantageous to wild populations during times of environmental change. In fact, it’s one way that some new species are eventually formed.   For the nursery propagator and gardener, hybrids can be  a source of plants with new, desirable traits.   So easy hybridization does have its positive side.

On the other hand, the propensity of Buckwheats to hybridize has plant ecologists worried.  As native gardening increases, plants once separated geographically are now coming in contact.   Hybrid Buckwheats are beginning to pop up in home gardens.   More alarmingly, hybrids are also occurring among wild populations of Buckwheats!  These hybrids are a direct consequence of plants in gardens and highway plantings:  bees transport pollen from garden to wild land -  and hybrid  plants are the result.

While hybridization may seem innocuous, the potential consequences are serious. The very characteristics that differentiate one species from another are in danger of becoming lost.  Each species has intrinsic value - in addition to its potential as medicine, food or other material.  The loss of a species is not something to take lightly; once lost, a species may be lost for good.   

Some scientists argue that buckwheat species should only be planted within their precise local range. That’s probably a good idea, although a bit late in coming in the case of Buckwheats.   At the very least, we should consider the impact of our gardening choices.  If you live near (say within ½ mile) of a population of wild/natural Buckwheats, consider planting only plants derived from the local population.   That’s a responsible choice; one that will help conserve the local native genes.  If you live in an urban area, your choices are more open, but you still might want to choose a local native species over one from further afield.  

 

 

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