Archive for August, 2010

Sensationally Simple Sedums

I often have people ask me in the nursery for easy groundcovers that fill in fast, dense and don’t need attention.  There are a lot of things to choose from in that category, but unfortunately most of them have a malevolent side- they don’t just peacefully occupy the ground, they are hell-bent on acquisition!  Advancing, strangling, unrelenting invasive groundcovers are not usually what a person has in mind when they ask for something ’easy’. Especially when you can’t get it out again!

Sedums are often my answer to groundcover in hot, dry or otherwise difficult sites in full or part sun.  Juicy, delightful little plants that grow in horrible soils and come in a wide range of shapes and colours, Sedums can be stuffed in rock wall cracks, hung in a basket or planted in those shallow, impossible windowboxes that won’t support as much as a geranium through one hot day. Sedums are most often the plant of choice in green roofing, too- they thrive when fully exposed to the elements and given sharp drainage.  Sedums can live happily where other plants fear to tread.

Sedums come in a dazzling array of colours, forms, shapes, growth habits and cold tolerance.  The one thing I would watch for when purchasing sedums is the zone hardiness, make certain they will make it through the winter.  Not all sedums love full sun either, there are a few that prefer part shade to quite shady, like sedum makinoi ‘ogon’ that sells itself with it’s cheery little lush gold leaves and then often disappoints if treated like other sedums and left fully exposed. Morning sun or partly shady conditions are best for this adorable gem.

Sedum acre growing in granite in Sweden

Sedum acre (aka ‘Wallpepper’ or a host of other names) will grow absolutely everywhere, and only the fact that it’s quite easy to remove redeem it from being a horrifically invasive plant. I like it as a green, matte base for slightly larger shrubs and perennials, it looks like moss from a distance and ‘takes’ fast and easily to cover the soil when I plant something new.  It turns into a raft of bright gold when in bloom in midsummer. I find it to be reliably evergreen in zone 7 and it colours up with a wine tint during winter.

Sedum spathulifolium has a special place in my heart- I love the look of it, a bold silver, and its original parent also a native plant.  I’ve found it growing locally, but it’s never quite as silvery as the nursery cultivars. (Sedum ‘Cape Blanco’ is most commonly found.) I find it to be a bit slower growing than many, so give it some space or plant with less aggressive plants so it can show off.

sedum 'Angelina'

Sedum rupestre ‘Angelina’ is a top performer in the garden.  It looks very good in hanging baskets and containers

too, especially the ones you forget about in the corners (you know which ones!) Golden yellow, fast growing and holding it’s shape and colour through winter, this one is a crowd pleaser and fills in fast and dense almost anywhere.  Sun exposure can change the colour, Angelina will grow in shade, but will be lime green instead of gold and not grow in as thickly.  In full sun it will develop hints of orange in the yellow.

sedum 'dragon's blood'

And finally, my favourite red is Sedum spurium ‘Dragons’ Blood’. It has a good ruby colour in full sun and the pleasant bonus of almost red but actually really deep pink blooms that don’t clash with the foliage! It is not as lush during winter but still present and contributes some colour, in summer it’s that dash of deep wine-red that can be hard to achieve with hardy plants and is very striking with plain greens. For almost-black foliage try to find some ‘Voodoo’, it’s even darker than ‘dragon’s blood’ and looks great with silvery or gold foliage.

Sedums are a large and diverse group of plants. Honestly, there are so many varieties and cultivars of sedum that I would need to write an entire book on the subject to begin to do it justice.  Just take a look in your local nursery and see what they’re carrying this month- it is possible to plant an entire rainbow of sedums and there’s certain to be something you like the colour and shape of.

Getting  Some

Luckily, sedums are an easily reproduced plant.  Small cuttings or big hunks are quite likely to take root if you simply toss them on the soil, but with a small amount of extra care you can have hundreds of baby sedums in very little time.  One large pot can become the stock for an entire swathe of garden if you divide it up, and a small handful from a friend’s garden giveaways is a great way to start growing these agreeable ground covers.  Simply tuck ends of sedum cuttings into well draining soil and give a little extra water in the beginning if the weather is dry and sunny to get them to root in quickly.

Then ignore and enjoy!



Okay, okay, I won’t do another one on a common fruit this month- I thought I might try instead, an uncommon vegetable- Goldenrod.

Goldenrod? Seriously?  I see you looking at the screen in bafflement…Goldenrod or Solidago has been saddled with a bad name, and one I think it doesn’t really deserve as it is an extremely useful plant in the ornamental and veggie garden, and it’s pretty smack-you-in-the-eye gorgeous when in full bloom.

Goldenrod in Fountain County Indiana

I both love and rue the Goldenrod in my garden- there’s a big patch of it that had become entangled with an azalea sometime before I took possession of the yard.  I’d sure like to see what colour that azalea is- but the goldenrod hogs all the nutrients and it has never bloomed.  Every year, I swear I’m going to dig out the entire plot, remove all the underground stems of solidago and let the azalea be what it should. And yet- when it blooms, glorious and gold in late summer, six feet high, it’s just so damn regal I just can’t bring myself to root it out.

Goldenrod is native to North America, with a sprinkling of species in Eurasia and South America, and one cannot peruse any text on ethnobotany without coming across the traditional uses of goldenrod in herbal treatments for colds, liver and kidney troubles, fever, skin ailments, nausea and as a general tonic tea. It was also included in some smoking mixtures or used as a smudge. To the Omaha tribe, it was an indicator plant that bloomed when the corn was ripening and harvest nearing.

Solidago canadensis

There haven’t been a lot of good studies on solidago, but it’s almost universally used by native Americans and Europeans alike for very similar reasons- I think there has to be some properties that haven’t been fully explored yet. The few studies that have been done reveal it to be anti-inflammatory, relieve muscle spasms, fight infections, and lower blood pressure.  It does seem to have diuretic properties, and is used in Europe to treat urinary tract inflammation and to prevent or treat kidney stones. In fact, goldenrod is commonly found in teas to help “flush out” kidney stones and stop inflammatory diseases of the urinary tract.  But herbal uses are just the beginning!

The young greens can be eaten as a vegetable, steamed and buttered in spring when still tender. The leaves, flowers and stems can be collected to make herbal infusions and teas. The flowers and seeds are edible raw.  And here’s another kicker-it makes rubber! Well, to be specific, it makes latex, but that can be converted into rubber quite easily.  Thomas Edison managed to breed a variety of solidago that yielded as high as 12% rubber.  (Incidentally, this is not the only plant to produce lots of latex.  Common dandelion is a great latex producer, too.)

AND- yes, there’s more to this multifunctional plant- it makes an unbeatable companion plant for the gardener- attracting massive amounts of predatory insects, butterflies and bees.  This plant produces a LOT of nectar and may just be the most popular plant in the garden in August, buzzing with activity.  It’s a must for butterfly gardens, many species find it highly attractive. Now- this is a bit icky, but if you’re an organic gardener you’ll appreciate it- this plant attracts hordes of aphids that are plant-specific, meaning they won’t touch the plants next to it. Mine’s always coated in grey aphids come late spring, but then the ladybugs arrive and begin to breed- there could not be a better nursery for ladybugs and other predatory insects. Simply put, if you want predators, you need prey- and you’ll have that in spades. And the goldenrod doesn’t even seem to CARE that it’s coated in bugs-it does just fine despite the annual infestation.

Carnica bee on Solidago

If all this wasn’t enough to encourage you to plant a little patch of goldenrod, the thing that makes it a pest also makes it a boon to amateur gardeners and people faced with a harsh spot where little else will thrive- Goldenrod will grow almost anywhere.  It prefers full sun but will make do with light shade, enjoys poor, rocky soils that horrify delicate perennials but will also grow in good garden soil (a cautionary note- it may go INSANE in good garden soil so don’t plant it where you’ll never be able to dig it out when it spreads. Or put it in a pot.) It is extremely hardy: Solidago canadensis is good to zone 3 and there are even hardier ones available. This is a plant that needs to be treated badly, in short.  Plant it in a pocket surrounded by packed, gritty soil- do not fertilize.  Cut back to the ground when the stems have died.  It will be well behaved and a valued addition to the garden- but give it good, rich garden soil and lovingly ladle compost on the plant as if it needed cosseting and it may become a rapacious monster, bullying less vigorous plants into submission.

Getting Some

Almost needless to say, goldenrod grows easily from seed that has been stratified (chilled in an artificial winter,) and can also be cloned from divisions of the original clump.  It should not be too hard to find a specimen in a nursery, but the consensus is still split between it being a weed or an ornamental plant, so it’s not carried in large numbers like fall asters, although they belong to the same family and bloom at the same time.  Purple asters, by the way, look fantastic paired with goldenrod! If you’re desperate for a plant and cannot find any in your local nurseries, you can probably find some walking in open areas in late summer, early fall- they are a native plant. Of course, I would never recommend digging up plants from the wild- but they can spare a root clod or two and there’s always collecting the seed.

Oh, and if you haven’t already found out- Goldenrod does not cause seasonal allergies! It has a heavy, sticky pollen that is carried from flower to flower by insects, not the wind. Something else is making you sneeze.

May your August be Golden;-)

I guess I’m on a bit of a campaign for plants that produce something useful or tasty, and that probably isn’t going to stop any time soon.  I do enjoy a useful plant in the garden!  The not-so-humble blueberry, however, is a plant most deserving of praise and planting in the ornamental garden. Or anywhere you can spare a place for two or three- or six or nine;-)  Where to begin?

How long have blueberries been around, really? The answer is just about the entirety of human history- the ancestors of the modern blueberry bush, which comprise a wide variety of Vaccinium species, are widespread and varied, ranging a wide variety of climates although most species are from cooler temperate climes.  A berry that is collected and dried easily, it lends itself to preservation in lands where food availability is very seasonal- and was used by nearly every culture in Europe and the Americas as a food source. The Vaccinium family includes such well-known berries as lingonberry, cranberry, bilberry, huckleberry and whortleberry- there are hundreds of them , it’s a large family. Common names for plants in the family vary from one region to another- don’t argue about the name though, just eat it!

There are a few people credited with the evolution of the blueberry- John and William Bartram certainly had some influence. An American naturalist when America was still a relatively new concept, John brought his son William with him on extensive collecting trips, teaching him how to draw and passing on his delight in the plants and animals of his native countryside.  Part of their work was to assess and recommend plants to the homesteads of Georgia- Vaccinium species were among them.  Also, John sent many packages of seeds and samples to various people in Europe, so quite likely some hybridizing occurred there as well.Another person given credit is Luther Burbank, a man responsible for the Burbank potato, Shasta Daisy and more than 800 other strains of fruits, vegetables, fodder and grains. However prolific Burbank was, though, he didn’t contribute much to the improvement of the blueberry other than noting that it was a berry of interest and should be developed.  The real makers of the modern blueberry are Elizabeth Coleman White and Frederick Colville.  Elizabeth was the daughter of a gentleman farmer and grew up farming cranberries, becoming interested in blueberry propagation in 1911, she collaborated with Frederick, Chief botanist of the USDA. They are the ones responsible for the transformation of the smallish, large seeded but incredibly delicious wild berries to the large, juicy berries on e-z pick sized bushes. Paying pickers to bring in the largest berries they could find, they doubled the size of berries, earning Frederick the George Roberts White Medal of Honor from the Massachusetts Horticultural Society for contributions to agriculture.  Elizabeth went on to help form the New Jersey Cooperative Blueberry Association in 1927.

Blueberries love acid, sharply draining soils. Wild blueberries are found on sandy, humusy soils- full of organic material like decomposing leaf litter but porous and fast to drain.  Yes, they do grow in bogs and will tolerate being partly submerged for short periods, but permanently waterlogged soil means eventual demise. Consistent available moisture is also necessary for good production. (I say this while two of my blueberry bushes regard me accusingly with singed leaves and a not-juicy-at-all crop because I forgot to water them while the weather was cool and we had little rainfall. D’oh!) Commercial blueberry farmers often mulch berries with sawdust to promote a more fibrous root system, and you can do this at home too, but don’t plant them in sawdust! Wood fibre takes nitrogen out of the soil while it decomposes, and blueberries have very low nitrogen requirements, but a light mulch yearly is enough fresh wood on the soil.  You can mix some black (composted) bark mulch into the planting hole when you put them in, but no more than 1/4 the total volume of your mix. Peat moss is good to use in your soil mix when planting, but remember that peat moss, though providing ideal acidity, is nutrient free- you’ll still need fertilizer, organic or otherwise. A balanced organic fertilizer will help build up the soil more than a chemical one, but a slow releasing granular fruit fertilizer or a rhodo/azealea fertilizer is the best choice if that’s your route.  In an organic fertilizer, anything slightly lower in nitrogen and higher in potassium & phosphorus would be fine.  In the Pacific Northwest you shouldn’t need aluminum sulphate or other acidifying additives.  If you don’t lime your plants, you’ll be fine-our soil tends to be naturally acidic.  Mulch with sawdust or (I like the look better) with composted black bark mulch over fallen leaves in fall. If your plants are not very green or not growing well, mulch with something ‘rich’ in spring like compost or worm castings.  Oh, and bone meal goes in the hole.  Bone meal always goes in the hole.  Situate your plants where they will get 6 hours full sunlight or more, the more sunshine they get the more abundant -and sweeter!- the berries will be.

The pollinate debate.  Blueberries are completely demanding princesses when it comes to pollination. Some people will tell you to obtain massive amounts of plants to ensure pollination, some recommend different varieties planted together, others say two plants is enough- none of them are wrong.  The straight dope is that blueberries require pollination multiple times per berry- if you want large ones.

‘According to Aalders (1958) every blueberry fruit should contain at least 6 to 10 viable seeds. When there are less than 6 seeds, the fruit may be small and/or drop prematurely. He reported that every additional seed is responsible for a 5% increase in fruit weight and a half-day advance in fruit maturity.

Fruit development is therefore directly related to the number of viable seeds which are set. These seeds produce “hormones” which act as magnets for drawing on the plant’s resources and making the fruit grow in size. The greater the number of viable seeds, the larger will be the size of the fruit and the greater will be the ability of the fruit to resist heat and water stress. Under poor growing conditions, fruits with few viable seeds will stay small and may abort or die. All attempts to increase the number of viable seeds within the fruit will result in a yield increase. In general, a little blueberry contains less than 8 viable seeds, a medium-sized blueberry contains 10 to 15, and a large blueberry contains 16 to 18.’ Department of Agriculture and Aquaculture New Brunswick

To add insult to injury, some cultivars are very infertile and won’t pollinate themselves.  This is where planting different varieties comes in handy, but be certain to get plants that are in bloom simultaneously, or your efforts will come to an unproductive end. Most highbush blueberries (most common in our temperate climate) are self fertile and if you have a cultivar name, you can check if the variety you have is self fertile or not.  Planting in multiples, whether they are the same cultivars or not, are always best- this method attracts more bees, keeps them around longer going back and forth, and exponentially increases the chances your flowers will be pollinated repeatedly. However you CAN get berries on a single bush that is self fertile. Chances of this being successful are better if you have other flowers that bloom the same time around Pieris japonica, other heaths and vacciniums, late winter/early spring blooming heather, etc. You probably still won’t get as many berries, or as large, but it is possible to get berries on one bush. But don’t you want lots of big berries?  Of course you do- so plant plenty of bushes.

Blueberry Varieties
Highbush blueberries are the most commonly seen type in our area. The vast blueberry fields in the lower mainland are almost exclusively northern highbush types. The plants, as the name suggests, grow quite tall, some to 6 feet if left unpruned. They produce some of the largest berries and are very cold hardy, most cultivars growing in zones 4-8, though there are individual variations.  ‘Bluecrop’ is the local industry standard as it is easy to machine harvest, but there are many worth planting in the garden that are not viable commercially.  ‘Chandler’ and ‘Darrow’ have the largest berries.

Half- high blueberries are a cross between highbush and lowbush types, with a height in the middle of the two.  They are even more cold hardy than highbush, and the berries, though usually smaller, are closer to the intense flavour of their wild cousins.

Lowbush blueberries have a much lower growing pattern, usually no more than about 1 1/2 feet high. These grow less like bushes, and in some ways are more like a groundcover. They spread through underground runners, and are not so much distinct bushes but more of a mass of plants.  Fruit generally forms on the second year’s growth. More difficult to pick, but extremely tasty ‘wild’ type blueberries are produced.

Rabbiteye Blueberries (aka Southern Highbush Blueberry, Southern Black Blueberry, and Smallflower Blueberry) are a southern crop, preferring zones 7-9.  They form extremely tall bushes as high as 10 feet, have excellent flavour and ripen later in the year then other types.  Rabbiteye has been developed from blueberries native to the southeastern states- they may also be referred to as Vaccinium virgatum or v.ashei.

There are always new plants coming on the market, as breeders hybridize the various blueberries to get new and ‘better’ plants.  Highbush, lowbush and rabbiteye have all been used to breed new plants, so it’s possible to get a rabbiteye/highbush/lowbush cross!

Wild Blueberries Dewey Lake QRP Backpacking trip

And now for the best part.  Blueberry bushes are pretty! Dense and bushy, easily pruned into shapes or hedges, with small but attractive flowers in early spring that attract bees, their real showmanship comes into play in fall when first frost turns the leaves scarlet, wine and orange.  When the leaves drop, they reveal stems in hot bright colors of red to gold depending on variety.  And there’s few sights prettier to me than a fully loaded bush of dusty blue berries on a hot July day!

To choose by ornamental value, here’s a handy chart with most of the commonly available blueberries in the Pacific Northwest listed with fall colours :

I think the health benefits of blueberries have been touted more than enough that I need not include any information on that front.

They are good for you, ’nuff said. Yum!