Fall is for Planting…Ornamental Grasses! But so is Spring…

I’ve written previously of my adoration for ornamental grasses.  A few of you folks in the mid-Atlantic might have heard my “Grasses for the Masses!”  presentation complete with lots of arm-waving. As with most of my talks, there’s usually some sort of interpretive dance involved.

Most of our warm-season ornamental grasses are in full gloriousness at the moment.  Because it’s autumn! ‘Tis the season to purchase, plant, and enjoy ornamental grasses!

Pennisetum 'Karley Rose' - available at a garden center near you!
Pennisetum ‘Karley Rose’ – available at a garden center near you!

Well, not really.  If you’d have purchased and planted them in April or May, you’d only have to do the “enjoy” part now.  And your local grower/garden center would LOVE you for it. But most gardeners overlook containers full of  6″ tall Fescue – which is what a LOT of our best grasses resemble in the spring.  It’s always been challenging to sell “green” in the spring – consumers want to see and buy plants in flower – so nurseries and greenhouses that supply garden centers do their darnedest to provide said blossoms.

Gorgeous grasses at Babikow Greenhouses near Baltimore, MD.
Gorgeous grasses at Babikow Greenhouses near Baltimore, MD.

So we pass over pots full of green grassy things in favor of enticing blooms. Nurseries have picked up on this – many include grasses in their summer/early fall production schedule, making full, fluffy pots for the autumn gardener.  This works o.k. for shorter, compact things like fountain grass, little bluestem, etc.   But by September, majestic switchgrass, big bluestem, and the like rarely look that fabulous in a one or two gallon pot – the proportions aren’t right; a bit of wind and rain and the situation is ripe for floppage (closely related to splayage). So you’ll probably pass them over. Again.  Or maybe…take a second look? Just cut them back and plant away – you’ll enjoy them NEXT fall.

Smoke ‘em if you’ve got ‘em…

(As an aside, I wrote this before I read Jeff’s Oct. 13 post so don’t read this as a rebuttal!)


One of the hallmarks of science is that it pays to keep an open mind.  We all tend to have biases so it’s good to get a reminder once in a while that some things that seem ‘out there’ can actually work and provide some useful information.


A case in point.  At the American Society for Horticultural Sciences annual meetings I make a point to wonder through and browse all of the poster presentations – even those that appear to have little relevance to issues I typically deal with.  This year one of the posters that caught my eye was by Orville Baldos and his colleagues at the University of Hawaii and the USDA on the use of liquid smoke flavoring to improve seed germination of piligrass.


So first, what’s piligrass and why would you want to improve its seed germination?  Piligrass is a native bunchgrass in Hawaii.  It’s used for conservation and restoration projects and there is increased interested in its use as an ornamental.  It is drought tolerant and fire adapted but production is limited by poor seed germination.  Where does liquid smoke flavoring come in?  Liquid smoke is produced by passing wood smoke through water (I assume someone somewhere has constructed the world’s largest bong to accomplish this).  The water traps a variety of chemical compounds in solution, many of which are useful in giving a delicious smoky flavor to foods that have never been near a grill.  Some of the compounds in liquid smoke are also useful in improving germination of seeds of fire adapted plants, or at least piligrass.


In their study Baldos et al. found that germination of piligrass seeds soaked in distilled water was a paltry 0.5%.    In other words, you’d have to sow 200 seeds for each plant you hoped to produce.   Soaking seeds in gibberillic acid (a common method to improve seed germination for a variety of plants) bumped the germination rate up to 20% (5 seeds to get one plant).  But soaking seeds in liquid smoke did better still and doubled the germination to 40%.


At the end of the day it’s unlikely that I’ll ever use liquid smoke for anything except adding a little extra zing to my family’s secret barbeque sauce.  But this study is a good example that sometimes things that make you go ‘What the heck?’ can have merit in the end.  Just need to take a scientific approach and keep an open mind.


For those interested in the details here’s a link to the poster http://ashs.org/abstracts/sites/default/files/updated_ashs_poster_091911.pdf

Lasso those grasses!

While Jeff and Bert were swilling beers and eating burgers last weekend (dang, wish I was there to commiserate!) I was whacking back the last of the perennials and grasses in our home garden.  Tarp after tarp were filled with winter’s debris for compost pile as we fought 25 mph gusts the entire time.  Not ideal conditions.  However, a neat trick I learned years ago came in handy with the grasses.  I’m assuming many of you utilize this technique also – so forgive me if this is a “nothing new” post  Here’s Paul and Dabney, our Hahn Horticulture Garden horticulturists, demonstrating said technique:

Just cut below the web strap or rope with your favorite implement of destruction, and toss the whole bundle on the tarp to get it to the pile. Note that they both have on safety glasses, and Dabney has on gloves.  I can’t stress enough the importance of gloves (and long-sleeved shirts) when handling dried grasses. One of our student workers sliced his finger open to the tune of three stitches last week.  He was cutting down Arundo donax, Paul asked him to put some gloves on, but since 22 year-old guys are indestructible, he blew off the advice. Just saw him working out in the garden today with gloves on, yay!

Weigh in with YOUR garden clean-up tips – ’tis the season (for most of us north of USDA Zone 7 in the northern hemisphere).

Garden Professor Trivia #2: Who’s the tallest GP?

[This could get interesting…Oldest! Weirdest! Heaviest drinker! Most traffic tickets! Most cats! Most obsessed with slugs! etc.]

Pampas unpuzzled

Great discussion and answers on this one, gang!  Yes indeed, this is a plant out of place – as several of you noted.  But not only has it escaped from an ornamental landscape, it’s decided to grow, quite happily, in the median strip of I-5:

Another odd thing is that the species has not been officially recognized as invasive in Washington State.  It’s been languishing on the “Monitor” weed list for at least two years.  Our climate is a bit chilly for it, which may be part of the reason it looks so bad right now.  We had a very cold week back in November which may have killed this specimen back to the crown.  But never fear.  New growth will emerge this spring.  (Note to Washington State weed control board – maybe it’s time to list this plant as invasive???)

Finally, I do believe this specimen was sprayed last spring, as Jimbo pointed out.  However, it recovered and was able to send up two seed heads…which I’m sure have lavishly sprinkled the surrounding soil.