Graft and corruption

It’s election season – but that’s not why I’m doing a blog on “graft and corruption.”  Instead, let me back up and explain that today I gave a seminar on diagnosing urban tree death.  One of my points to the group was the importance of knowing the history of a site – what species were selected, how trees were planted, whether there had been any major construction activity, etc.  I thought I’d continue the importance of site history into today’s posting.

Here’s a photo of a street tree – a Prunus spp.  (Disclaimer: I am not endorsing a candidate for Mayor of Seattle despite the appearance of a campaign sign in the photo.)  It’s a healthy enough specimen, though possibly a bit large for this narrow planting strip:

Several years ago you would have seen a different tree in this same spot:

Now did this weeping cultivar somehow transform into an upright form?  Let’s look at this second photo in its entirety:

This reminds me of my favorite childhood book on Greek mythology, which had a great drawing of Athena springing from the head of her father, Zeus.  Yes indeed, we are seeing the scion of a grafted tree lose the battle to the rootstock.  Rootstocks, by their very nature, are vigorous.  If we revisit the first photograph again, this time a little closer, we can see all that remains of the poor scion:

Lesson:  if you are using a grafted tree in the landscape, you need to keep the rootstock under control.  Grafted trees are probably not good choices for low-maintenance landscapes.

Where the Buffalo Roam

Just kidding. We have no buffalo on the campus of Virginia Tech, just lots and lots of students with the flu. Yuck.  But this is much more interesting:

Bouteloua dactyloides (bless you!), better known as buffalo grass:

We’ve recently added a 1-acre meadow to our on-campus teaching and display garden (the Hahn Horticulture Garden at Virginia Tech).

Native trees, shrubs, perennials,and grasses surround a central lawn of buffalo grass. As one of the components of tall- and short-grass prairie, it is a popular forage in the west and midwest. Toughness and no-mow-ability makes buffalo grass a candidate for the low-maintenance lawn. We chose the cultivar ‘Bowie’, which has been reported as a good choice for the Mid-Atlantic…more cold and moisture tolerant.  But it’s not cheap – ran us $15/lb with a seeding rate of 3lbs/1000 sq ft. We ordered 1/4 acre’s worth. Our horticulturist Paul calibrated the spreader not once but three times, and was still nervous.

We’re pretty happy with the progress – it’s filling in nicely after 18 months. Once established, buffalo grass will pretty much choke everything else out, but until then, broadleaf weeds and crabgrass are a bit of a pain. Extremely drought resistant, it also handled this year’s surplus rainfall with no problems.

The best way I can describe it is, er, cute!  It’s so fluffy, and forms pet-able 6″ tall tussocks with little seed heads dancing about. One just might, after a hard day of academia-induced anxiety, want to lay down in it and make a “grass angel”.

We’ve already had a light frost, hence the tawny color. This presents a teaching opportunity:  most of the turf around here is tall fescue or blue grass – fairly evergreen, cool-season grasses. Buffalo grass WILL turn golden-brown in winter, and we’ll get lots of questions as to whether or not our meadow is “dead”.  No, it’s just resting!

If you’re thinking of trying buffalo grass or something other than run-of-the-mill turf for your lawn (or even ripping it out altogether), check out ideas from Susan Harris and friends at www.lawnreform.org

Moo... So there's a weed or two...

RAWRRR!

Posted in honor of Garden Rant’s Halloween-related garden photo contest.

Pick me, Amy, pick me!!!



Now For The Scary Part

This little dude is the Florida Semaphore Cactus, native only to hardwood hammocks in the middle and lower Keys. According to the Center for Plant Conservation, Opuntia corallicola may very well be the most endangered plant in the United States.”  Only one wild population remains (eight individuals), plus a few sites of re-introduction. Loss of habit and an exotic cactus moth have contributed to the demise of this most personable of cacti.

Arbitrary travel tip: I snapped this photo during a recent visit to the fabulous Key West Tropical Forest & Botanical Garden. Please pay them a visit if you’re ever in the vicinity – they are doing so many great things, with so little $$$, as is the case for many small public gardens. And then head straight to Kelly’s on Whitehead Street for outstanding $3 margaritas…served in a pint glass!

Alternatively:  "Aieeeee!

The Heartbreak of Plagiotropism…

…Otherwise known as “splayage”. When vegetatively propagating some species of woody plants, care should be taken when selecting where to take a cutting (piece of stem) to root.  Propagation from terminal cuttings (pointy end up) usually results in orthotropism or a vertical growth habit.  Cuttings from extremely lateral branches (those that grow parallel to the ground) can, in a few species, result in a spreading growth habit or plagiotropism.

This is not always undesirable – some species are purposefully propagated this way to maintain the prostrate habit that particular cultivar is known for. I’ve propagated lots of Buddleia over the years and don’t recall having this happen. Jeff, you were “Mr. Buddleia”* back in our days at UGA…please weigh in on this!

Floppulence
Buddleia davidii ‘Santana’, author’s garden.

Said plant was purchased from a little Mom & Pop greenhouse as a 4.5” pot with a 6” tall rooted cutting, and it went into our garden in May. It is now lolling all over its neighbors like a drunken sailor.  What looks like a vertical piece in the back is simply propped up by the Canna. No big deal, just a good teaching moment.

‘Santana’ is a bit slower-growing than most cultivars of Buddleia, yet is in great demand due to the wacky variegated foliage. My guess? This is the result of repeated acts of propagation via lateral branches…cuttings of cuttings of cuttings. Not to mention the fact that it’s patented, so this guy may not only be floppy, but illegal (!). One of the purported upsides of the plant patenting process is to control the quantity and quality of propagation through licensing. But that’s another post topic for the future.

*Not to be mistaken for the pageant winner “Miss Buddleia”

More Good Stuff from the Garden Writer’s Conference in Raleigh

I should add “in absentia”… Played hooky from the convention center Thursday afternoon for a trip out to Plant Delights Nursery, Inc. with my former grad student and plant geek extraordinaire, Paul Westervelt. We followed proper Plant Delights etiquette: you make an appointment to visit at a time other than open house or tour. I teach herbaceous landscape plant i.d. as well as ornamental plant production courses, and take every opportunity to bring back images of new technology, growing systems, and great plants to my students.  Since Paul is a now a grower for a large nursery, he’s also keen to learn anything he can.

We certainly didn’t go to shop [“She lies!”].


Tony amongst the yucca pups.

Even though we arrived a good hour before our appointed time (we were…excited), and even though a throng of 500+ salivating conference attendees were to besiege him and his staff the next day, owner Tony Avent very kindly made time to give Paul and me a personal tour of the back 40: where the real action is. Tony patiently answered our gazillion questions and filled our pockets with seeds. The propagation houses and trial areas have more amazing plants than you can shake a stick at. Many are one-of-kind hybrids or species. The vast Colocasia trials actually gave me goose bumps – alas, no photos were allowed. A walk through the display and trial gardens (Juniper Level Botanic Garden), resulted in several trips back through the retail houses to find that OMG! plant we just saw. We topped our visit off with the purchase of way too many yummy plants. Delightful, indeed!


The trial and breeding collection of Epimedium species and hybrids. Who knew there were that many???


North Carolina or Hawaii?? That’s  Colocasia ‘Diamond Head’.


I’m in an Agave/Yucca phase and this isn’t helping a bit.


Paul demonstrates “The Joy of Plant Shopping”.

Fabulous Sporobolus!

“Where have you been all my life?!!”

Every once and a while, I come across a plant and simply fall in love.

I  am not alone on this particular species, and the bandwagon is getting mighty crowded.  Sporobolus heterolepis is the object of my affections…it even has an intriguing common name – Prairie Dropseed. It’s native to much of North America, short of the West Coast.  Though most widespread in the Midwest, there are isolated populations in Virginia, North Carolina, and Pennsylvania. It’s even hardy up in the Arctic North (where Jeff and Linda live).


Sporobolus  shows off some  fluffitude while Echinacea tennesseensis look on in amazement.  Author’s garden.

Now on to the juicy description: fine, green foliage forms fluffy mounds or tussocks up to one and a half feet tall and up to two feet wide.  I describe it to my students as “pet-able” – one just wants to run their fingers through the flowing locks… The tiny, fragrant  flowers appear in late summer form a fluffy cloud above the foliage and wave about on slender stems, even with the slightest breeze.  I think the flowers have a coriander scent, have also heard buttered popcorn and vanilla.  Seeds form and then drop to the ground around the plant (hence the common name), at which point the birds scarf them up.  There is very little actual germination; the species is in fact endangered or threatened in several states (USDA Plants Database).  As the weather cools, the fall color can range from bronze to orange to apricot – just gorgeous – and then turns to a tawny buff for the remainder of the winter.

Newly-planted in the Hahn Horticulture Garden at Viginia Tech – check out that fabulous fall color!

As with many prairie natives, this a very tough character once established – puts up with lousy soil,  little rainfall, and is definitely drought-tolerant. We’ve added more than 100 of them to our campus meadow garden.  At my favorite public garden, Chanticleer (Wayne, PA), they’re planted in huge drifts and are managed in the “natural” way, with controlled burns in the early spring.

Doubt you’d find it at a big box store, but it should be available at an independent garden center near you! Please note this one of those species that does NOT look very exciting in the pot, especially in the spring (green, grassy, that’s it).  But give it a season or two in your garden and…[cue romantic violins…].