Monday, July 29, 2013

Groundcover Review: Sweet Woodruff, Galium odoratum

Galium odoratum, Sweet Woodruff in early July, nestled between a tattered aquilegia and a glossy camellia
Galium odoratum, Sweet Woodruff in early July, nestled between a tattered aquilegia and a glossy camellia

Sweet Woodruff, Galium odoratum

Pros:

- Evergreen (at least in zone 6/7)

- Beautiful light-green foliage with an interesting whorled shape. That foliage stays clean and green throughout much of the year. As far as I can tell, Sweet Woodruff is not bothered by any insects or diseases.

- Tall and thick enough to block out weeds

- Spreads moderately quickly but mainly grows in spurts (autumn and spring, I believe). The patches I've got seem to reach their spring size and then stay that way. The fact that it's not constantly expanding its territory makes me think I could control it fairly easily if I needed to.

Sweet Woodruff seems to thrive best in shady spots. This one is sheltered under the canopy of a crape myrtle.

- Tough! Grown in partial shade, it survived last year's 100+ temperatures and brutal drought. Temperatures down into the teens and 20s this winter didn't faze it one bit. (It is hardy to zone 4.)

- Flowers a little bit in springtime. Well, my plants didn't flower at all their first year. They flowered a little this year. I've seen photos online with lots of (small) white flowers, so perhaps they'll have more flowers in future years.

- Some sources say that Sweet Woodruff can repel mosquitoes and that the dried leaves can repel moths.

- I believe the flowers were formerly used to flavor spring wine in Germany, but nowadays internal use is discouraged due to the fact that the plant contains a compound called coumarin that reportedly can damage the liver.


Cons:

- Not native to the Southeastern U.S. Sweet Woodruff comes originally from Europe.

I was worried that Sweet Woodruff would overrun Rozanne Geranium, but the geranium actually seems to have the upper hand. The kicker will be to see what happens next year. Because the semi-evergreen Sweet Woodruff will most likely expand in all directions in early spring before the geranium breaks dormancy. Which means the geranium may try to emerge right in the middle of the Sweet Woodruff next year. It will be interesting to see what happens as these two duke it out. Regardless, it looks lovely right now with geranium foliage and flowers intermingled with the Sweet Woodruff.


- Sweet Woodruff doesn't necessarily play nice with other small plants. I would say that thick lush growth that blocks weeds would almost certainly stop the germination of any annuals and could very well overwhelm smaller perennials. For instance, my largest patch of Sweet Woodruff is butting up against a hardy geranium (Rozanne) and has practically swamped some Smilacina racemosa (False Solomon's Seal). On the other hand, I can't see Sweet Woodruff causing any problems for shrubs, trees or any perennials that grow taller than say 6 inches. Cornell calls it aggressive, but not invasive and says other plants can come up through its foliage.

- Depending on your aesthetic standards, there's a point in late winter / early spring when you might not be too happy with the way Sweet Woodruff looks. The previous year's foliage does look good throughout January (at least here in zone 6/7), but there's a point in February or March when the evergreen / semi-evergreen foliage turns brown and crispy. Lots of websites will tell you to cut the old foliage near the ground in Spring to stimulate regrowth. Being an experimental sort of gardener - and figuring that Sweet Woodruff had evolved and probably thrived in the wild without anyone coming along to trim it back in the spring - I decided to leave it alone to see what would happen. After a few somewhat messy-looking weeks, fresh new green growth quickly obscured the tattered foliage of the previous year. And I'd guess that old foliage both protects the new foliage while it's emerging and then later feeds the plant as it decomposes back into the soil. So if you're not a perfectionist, I'd suggest going for the low-maintenance approach and forgoing the spring trim. If you prefer to keep your garden looking pretty all the time in case a photographer from House Beautiful drops by, I don't think there's anything wrong with trimming or probably even mowing the old foliage back to the ground in the spring.


Conclusion:

Sweet Woodruff is one of my favorite groundcovers. I'm planning on dividing and spreading this to several other semi-shady parts of my garden this autumn. I might even try putting a piece in full sun, just to see what happens, though I doubt sincerely that Sweet Woodruff would be happy in full Southern sunshine.

Monday, July 22, 2013

Groundcover Review - Hardy Blue Plumbago, Ceratostigma plumbaginoides

Hardy Blue Plumbago looking good in a morning sun / afternoon shade setting. This is how it looked on June 15th.

I'm a big fan of groundcovers - at least in theory.

Why are groundcovers Good?

1. Groundcovers block weeds.

2. Groundcovers prevent soil erosion / compaction

3. Groundcovers can themselves be beautiful and have wildlife value

4. Groundcovers knit the landscaping together

5. Groundcovers can be low maintenance and cost-effective. If you mulch your beds, you typically have to buy and spread new mulch every year - or pay someone to do it for you. Some mulches like pine bark may last 2-3 years, but even those mulches will often wash or blow away. Constantly refreshing your mulch is not very environmentally-friendly, it's not very kind on your pocketbook and it can be a big job depending on the size of your landscaped area

Hardy Blue Plumbago blooms earlier in a full sun setting, but the leaves look a little bleached and the plant seems less inclined to spread than the ones with afternoon shade. (Although the tendency to spread may have more to do with the fact that the partially shaded front foundation bed is more heavily amended than the heavy clay soil in this back full sun bed.)

So why do groundcovers get a bad rap sometimes? Groundcovers (as the name implies) need to cover ground, but some of them are too good at their job. They cover so much ground that they swamp everything in their way, smothering perennials, invading lawns (and even worse, sometimes invading natural areas), sometimes even tearing down trees (I'm looking at you English Ivy).

What are some of the other groundcovers that give the category a bad rap? Oh, plants like Yellow Archangel, Vinca, Bishop's Weed, etc.

That said, a few bad apples shouldn't give a whole category a bad rap.

So I've been trialing a number of groundcovers at Garden of Aaron to see which ones are tough enough to survive without much coddling yet not so rampant that they take over the property and kick me to the curb.

My preference (as with other plant categories) is to use native Southeastern U.S. plants - ideally Tennessee natives - but I've also tried some exotics.

So here is the first in a series of posts with my thoughts so far on my various groundcover experiments:

Hardy Blue Plumbago and Sweet Alyssum


Hardy Blue Plumbago, Ceratostigma plumbaginoides

Pros:

1. Tough. Made it through drought and 100+ degree temperatures in the summer of 2012 without a whimper. On the cold side, it's hardy to at least zone 6 (though some Dave's Garden reviewers report their Plumbago surviving into zones 5 and even into zone 4 around Minneapolis!)

2. Beautiful self-cleaning blue flowers from late summer to autumn (no need to deadhead). Attractive semi-glossy foliage.

3. Gorgeous red fall color

4. Not too aggressive or fast-spreading. Seems easy to control. Not listed as invasive as far as I know.

5. Does not seem troubled by any pests or diseases.  Some of the Dave's Garden reviewers report the plant surviving for decades in their yards with little human intervention. That's the kind of garden plant I respect and admire!

6. Seems to grow in sun or shade, but has spread further and looks happier with afternoon shade in Tennessee. Perhaps it appreciates full sun in the northern part of its range (hardy to zone 5)


Cons: 

1. Not a Tennessee native (originally from Western China)

2. Deciduous and Herbaceous. This is probably its biggest draw back. One of the main reasons to plant a groundcover is to deter / block weeds. If the plant disappears during the winter, that seems to leave the ground free for weeds to colonize. In reality - perhaps because of the Plumbago roots underground - I haven't really seen any weeds in the spots where the Plumbago was slumbering, but the herbaceous nature of the plant is definitely a concern. Oh and it wakes up quite late in the spring (late April in 2013), so in a climate like Tennessee, you're probably looking at 4-5 months of bare ground and the bare stems of last year's growth. (Incidentally, Missouri Botanical Garden says the plant overwinters better if those old stems are left uncut until the spring. I did not cut them at all, and the new foliage quickly grew up and covered the old stems. So I'd say it's very low maintenance in that regard.)

3. Does not seem to have much wildlife benefit. I don't recall seeing any pollinators at the flowers, nor did I see birds going after any seeds. (Some sources actually say that Hardy Blue Plumbago can do a good job of attracting bees and butterflies...maybe I just need a larger patch of the flowers to get the pollinators' attention? I'll keep a close eye on them this year and report back if I spot any beneficial insects.)

4. Spreads slowly. This is an attribute from a control standpoint (you don't have to worry about it taking over the whole flower bed when your back is turned), but means you'll need a lot of plants and/or a lot of time if you hope to cover a large amount of ground. I have not tried dividing the plant yet to accelerate its spread. This year, the plants in the front of the house (in partial sun and looser soil) seem to have expanded their coverage, but the plant in full sun and more compacted soil looks pretty much the same size as it did last year.

Conclusion:

Recommended, but with reservations.

UPDATE 12/13/15 - I would no longer recommend hardy blue plumbago. In fact, I've done my best to rip my patch Ceratostigma plumbaginoides out of the front foundation bed this autumn. 

From an aesthetic standpoint, I did not care for the foliage, the growth habit or the fact that its deciduous nature meant that it did a poor job as a groundcover for 5-6 months of the year. The deciduous aspect would be less of a concern in a climate with dependable snow cover, but here in Tennessee, where snow cover is usually bare or non-existent, a deciduous groundcover equals bare ground.

And then there was the aggressive/pushy/invasive nature of the plant. It's not a rapid spreader - at least in my heavy clay-based soil. I didn't find it traveling 10 feet underground in a single season. But slowly, inexorably, it was pushing outward and over-running other small perennials in its path. When I tried to pull up pieces of the groundcover, I found an extensive and deep network of criss-crossing roots underground. Those roots tended to break easily if pulled, making it quite a chore to uproot a patch of hardy blue plumbago.

As I discuss in my upcoming roundup of recommended groundcovers, I believe that the ability to uproot and easily remove pieces of a groundcover - or an entire patch - plays a major role in determing the garden worthiness of a plant --- especially a non-native / exotic plant.

So yep, hardy blue plumbago joins blue star creeper and creeping raspberry on the Not Recommended list of groundcovers.

Which groundcovers do I recommend as of December 2015? So far, some of my favorite herbaceous groundcovers include the cranesbill geraniums (especially Geranium sanguineum and G. x cantabrigiense), lamb's ear, wall germander, rose petty, Geneva bugleweed, Coreopsis verticillata and Epimedium x perralchicum 'Frohnleiten'.

Monday, July 15, 2013

Oh the Dreadful Wind and Rain!

It was a particularly wet and windy spring at the Garden of Aaron.

But wind is a familiar them in my garden.

In the winter, there's the bone-chilling wind out of the Northwest.

In the summer, we sometimes face a hot and dry wind out of the South that can stress and crisp even those plants that are supposedly heat and drought tolerant.

So my question to all you expert gardeners out there is this: In your experience, which plants are best suited for a windy garden?

I'm interested in all suggestions, including annuals and perennials, but I'm most interested in shrubs and trees, particularly those I might be able to use to construct some sort of windbreaks to protect the less wind-tolerant plants from the harsh winds of fate (and Mother Nature).

Here are some of my own observations from our exposed hilltop garden:

Natchez Crape Myrtle
"Natchez" Crape Myrtle stands strong against the winds that rip across our hilltop garden. 


1. Crape Myrtle (Lagerstroemia indica) shows up on lists of wind-tolerant plants. (Here's one list, here's another.) I agree - to a point. The branches are very good at bending rather than breaking in gale-force winds and the leaves seem tougher than say maple or redbud (see below). But the leaves do get awfully tattered - especially if the winds hit right when new foliage is emerging. I don't expect leaves to look pristine at the end of a growing season, but crape myrtle leaves can get ripped up by the wind and chewed up by insects to the point where they seem shredded fairly early in the season.

Vitex agnus-castus flowers just starting to bloom.
Vitex agnus-castus flowers just starting to bloom. Note how clean and fresh the foliage looks despite the fact that the plant is sited on a windy, hot, full sun corner next to the garage and a baking concrete driveway. Vitex seems cool as a cucumber and perfectly at home.

2. Vitex agnus-Castus (a.k.a. Chaste Tree) made it onto a list published by the Houston Chronicle of trees most likely to survive a hurricane. I'd call that wind-tolerant. (Crape Myrtle was on the list too...) I've got to say, I've got our Vitex right at the corner of our house where it can buffeted by both Northern and Southern winds. So far, it's looking good. I think there was some minimal branch breakage from winter storms, but the spring and summer winds haven't fazed it and the foliage is looking good - clean and fresh, with no signs of stress and hardly any signs of insect predation. I've read comparisons of Vitex vs. Crape Myrtles where people say that Crapes have a denser canopy and are thus better for providing privacy, but I have to say that our young Vitex actually seems far denser than our young Crape Myrtles. Maybe the Vitex canopy opens up more as the tree gets older?

Overall form of young Vitex agnus-castus tree/shrub planted last autumn. Foliage seems relatively dense at this point despite comments to the contrary on the World Wide Web.
Here's a young "Petite Snow" crape myrtle, also planted last autumn at the same time as the Vitex. I'd say the foliage on this is actually much less dense than the Vitex foliage. Also, the Vitex is covered with buds and blooms in its first full year in the garden, whereas there was nary a bud or flower in sight on this crape myrtle in mid-June.



3. Maples and Redbuds both seem stressed by our hot dry winds. In fact, I had two young maples die on me last year. For some reason, I still let myself get talked into planting two new maples in our front yard. Neither of them looks happy in the hot winds of summer. In fact, despite lots of water, some of the leaves are turning color, which I know is not a good sign. The redbuds look slightly more wind-tolerant, but their leaves hang awfully limp when it gets hot, almost like they're panting in the heat.

Cercis canadensis, Eastern Redbud, leaves look stressed

Maple leaves looking stressed. Never a good sign when your maple leaves are changing color in July.


4. Juniperus virginiana, Eastern Red Cedar also shows up on lists of plants suitable for windbreaks. http://plants.usda.gov/factsheet/pdf/fs_juvi.pdf  Our landscaper planted three of these on the hill. They're not looking all that great, but I think that's due less to the wind and more to the fact that we wanted large trees for instant landscape effect but we ended up with sort of small root balls on those trees. Not a good combo. In general, I feel I learned from this past winter that it's probably better to start with smaller trees that would probably be less-stressed by the transplant process. Anyway, I'm not in love with the Eastern Red Cedars. Probably because I find it hard to get too excited about most conifers. But I have to admit that they do seem to be fairly wind-tolerant. 

The shiny and waxy leaves of Camellia sasanqua seem wind-tolerant.

5. Camellias - I don't think most people would think of camellias as being tough plants, but apparently they are surprisingly drought-tolerant and even recommended for windbreaks. Our camellias are in somewhat sheltered settings, but I have to say that they have not seemed fazed at all by last year's heat/drought or by any of the winds that whip around the house. I'm thinking more and more about incorporating these into my windbreak and screening plans. The only problem that I can see is that they don't necessarily grow all that fast in my experience, especially when they are young. So if I plant a small tree - one that would be less likely to suffer transplant shock - it might take a long time to grow to the height and density where it would really help block the wind and provide privacy.

Aronia melanocarpa, Black Chokeberry also seems to be relatively wind-tolerant 

6. Aronias, Chokeberries - Also in a somewhat sheltered spot, but I've got to say that their (second-year) foliage looks really green and fresh this year despite the strong winds of spring and early summer. They definitely looked stressed last year (more by the heat and drought than the wind, I think), but they're looking much better now. I'd need to try them in a less-sheltered spot first, but I could see these trees doing well in a windy situation and/or even potentially being part of a mixed wind break. (Really beautiful foliage, incidentally. Sort of what I have in my mind's eye when I think about what a tree leaf should look like.)

And here are some other shrubs and trees that I'm considering adding to the garden / landscape. Any thoughts based on experiences in your own gardens and/or visits to other gardens on whether any/all of these would be wind-tolerant and/or suitable for windbreaks?

Sunflowers bloom just as cheerfully even after they've been bent sideways by 60-70 mph winds

As for smaller plants, I've found that high winds will bend sunflowers (although they'll usually keep growing), topple cosmos (although they'll often keep growing too) and break plants like Caryopteris and Coneflower. (To qualify that, most of the coneflowers survived the wind storm and look none the worse for wear, but I did lose a couple.) I lost one stem on Hibiscus moscheutos too, but the rest of the plant seems fine.

Callicarpa americana, American Beautyberry. I'd call this an open, lanky shrub (at least in its youth). The leaves will get burnt by strong, hot winds. Despite glowing reviews from some online reviewers, I can not recommend Beautyberry for your garden.

Beautyberry (Callicarpa americana) also seems much happier this year now that I've moved it away from a windy spot to a somewhat sheltered area.

Other perennials, annuals and shrubs that have stood tough and seem relatively unfazed by the winds include:

  • daylilies
  • zinnias
  • French marigold
  • love-in-a-mist
  • creeping raspberry
  • penstemon
  • Phlox paniculata
  • ironweed
  • Veronica (spicata and umbrosa)
  • liatris
  • Malva sylvestris
  • gaura
  • Russian Sage
  • Coral honeysuckle
  • Indian Hawthorn
  • Boxwood
  • Hardy Blue Plumbago
  • Hardy geraniums,
  • Helianthus microcephalus
  • Little Bluestem
  • Salvias
  • Platycodon
  • Monarda
  • Agastache
  • Ilex glabra (inkberry)
  • Azaleas
  • Fothergilla
  • Aucuba
  • Hypericum
  • Joe-Pye Weed
  • borage
  • stachys
  • ajuga
  • Hibiscus moscheutos
  • Heliopsis helianthoides


So...what are your most wind-tolerant annuals, perennials, shrubs and trees? 

And which are the ones that are pushovers (literally) when it comes to getting blown around by the winds?

My dream is to look out the window and not feel that my plants (like the maples and redbuds) are getting tortured by the winds. I'd love to find plants - especially shrubs and small trees - that are wind-tolerant. Heck, I'd like to find plants that revel in getting their leaves ruffled about by the wind. I want to find plants that look as though they're tossing their branches like a model tosses her hair back for a photo shoot or a walk down the runway. And hopefully these stalwart windbreak plants will help reduce the howling gales to manageable breezes so that I can grow more tender waifs in the sheltered microclimate they create.

Is that too much to ask? :-)

PS - The title of this post comes from a lovely but haunting folk song...

Monday, July 8, 2013

Help Wanted: Best Quick Privacy Screening Shrubs for Zone 7?


Here's the scenario: We moved into our home about two years ago. The development and the surrounding houses are around 6-7 years old, but many folks still seem to prefer huge expanses of grass to any large trees or bushes.

As a result, there's not much privacy -- except on the back patio, where several crape myrtles have grown big enough to provide some shade and screening in the warmer months. (Not so much in winter and early spring when the crapes are bare and leafless.)

I'd like to plant some large shrubs near the periphery of the property. Here are the parameters:

1) Fast-growing. Typically, I know that gardeners should not be inpatient, but we might move on in a few years and it would be nice if we could get at least a little privacy before then. I could just start with larger plants, but I feel like that plants settle into the landscape much easier if they're transplanted when they are still young. (The maples, redbuds and Eastern Junipers that our professional landscaper installed last winter all seem to be struggling in the summer heat, despite the fact that this is actually a relatively mild summer so far and despite the record rain and cool weather we enjoyed this spring.)

2) Dense. Well, I'm planting these for privacy / screening, so having an airy see-through shrub wouldn't make much sense! :)  Evergreen would be ideal, but not necessarily a conifer. And I'm not opposed to having deciduous shrubs in the mix since I spend most time outdoors in warmer weather anyway when the bushes would have leafed out. Also, I know that some shrubs with a dense branching structure can provide some privacy / screening even if they're deciduous.

3) Hot and sunny. Because none of the neighbors have many trees and we're on top of a hill, the backyard is windy, full sun pretty much from morning until night. These plants have to be able to take the heat and they have to be drought-tolerant -- both on general principal and because I don't know how often I can lug a hose to the edges of the property. Oh and they have to be able to handle clay soil and wet winter conditions. Is that asking too much?

4) Not too big. I don't want to be a jerk and put plants on the perimeter of the property that tower over the neighbors' yards. I think my ideal shrub would be the 8-10 feet range. I wouldn't mind something that topped out a bit taller (12-15 feet?) or could be kept in the desired range by being trimmed once a year. And of course I'm not going to plant it right on the property line, but well within our property so that the mature plant should not hang over into the neighbors' space.

5) Safe. Several of our neighbors have small children, ergo I would not want to plant anything that's even mildly toxic. A surprising number of common landscape plants are poisonous (for instance, yew, daphne, wisteria, azalea, etc.) I was excited at the notion of using a native holly like Ilex opaca or the Ilex attenuata hybrid, but some sources like NCSU list the berries as being slightly toxic. Even though the USDA calls I. opaca non-toxic, I'd rather err on the side of caution and not put such a plant near the edges of my property.

6) Climate suitable. We're on the cold side of zone 7. (We were in the warm part of zone 6 until the latest USDA zone refresh.) Temps regularly fall into the high teens in the winter. Summertime highs often hit the 90s and sometimes even climb into triple digits. Average annual rainfall is around 47-inches. Average annual snowfall is supposedly 10-inches, but in the few years we've been here, snow has been exceedingly rare. Ice is a more likely (and more frightening) possibility.


So, here are the plants I'm considering, along with why they're on the short list. If you've grown any of these and have an opinion as to whether they'll fit the bill, please chime in. Or if you think I've missed something that should be on the short list, please let me know! Thanks :)


Raphiolepsis umbellata, Indian Hawthorn
Raphiolepsis umbellata, Indian Hawthorn, not sure which variety, but definitely a variety that grows too low to provide any privacy screen!

1) Raphiolepsis umbellata, Indian hawthorn: We have several of these as foundation plants and they have been carefree and bulletproof since we moved in. They're not terribly flashy, but they do have nice pink flowers for a brief time in the spring. They're evergreen and supposedly prefer partial or full sun, although again ours seem to be thriving in a mostly shady area underneath a large crape myrtle. (I guess they get a lot of afternoon sun in winter and early spring when the crape has dropped its leaves, but they're mostly in shade the rest of the year.) Supposedly they're able to handle heat, humidity, wind, drought and rabbits. A nearby nursery carries a variety called Southern Moon that supposedly can grow 5-6 feet tall and 6-8 feet wide. The thing that gives me pause is that the varieties we already have are very low shrubs (maybe 2-feet tall by 5-feet wide). I don't know if they usually grow wide before they grow tall or if Southern Moon would have a more upright growth habit. I believe they are also supposed to have a slow growth rate. There's another variety that intrigues me called Montic (a.k.a. Majestic Beauty) that I've seen described as everything from a 5-foot tall shrub to a 25-foot tall tree. Sounds very variable!


Vitex agnus-castus, Chaste Tree, Monk's Pepper
Vitex agnus-castus, Chaste Tree, Monk's Pepper


2) Vitex agnus-castus, chaste tree, monk's pepper - It's the right height -- supposedly grows up to 25-feet tall in zone 8 or 9, but I've read that it would probably stay closer to 8-10 feet tall in Tennessee. Based on my experience so far, it definitely seems able to tolerate heat, rain, wind, full sun and flying bowling balls. (OK, probably not that last one...) The flower are bee magnets, which I love. In my experience, it has a decent growth rate. The only real drawback I can see is that it is deciduous and leafs out as late as the crape myrtle (mid-April).

Small crape myrtles don't necessarily offer much in the way of privacy

But mature crape myrtles can definitely help block a view or provide some shade - all while providing a long display of summertime flowers that attract some bees

3) Lagerstroemia india, crape myrtle - Speaking of the crape myrtle...I know from 2012 that these are tough as nails and can handle punishing heat and drought (at least once established). They also grow fairly quickly (1-2 feet per year or more) once they've settled in. And there are some nice-sounding varieties like Catawba that are available at local nurseries and reportedly mature around 12-15 feet tall. The flowers seem intermittently attractive to bees (they were all over the flowers on the Natchez Crape when they first opened, less so now). Of course, as I just mentioned with the Vitex, crape myrtles are deciduous and take a looooong time to leaf out in the spring. So, not a lot of privacy in winter. They're also ubiquitous (for good reason) in the landscape around the neighborhood. Personally, I have about 10 of the plants on my property, so I'd prefer to add something different for the sake of biodiversity. The final kicker is that none of the three young crapes I added from a local nursery last winter have grown at all. Two are looking fine and one (that gets blasted with wind at the corner of the house) looks a bit ragged. None show any inclination to bloom. So my experience leads me to believe that small crapes probably need some time to settle in before they grow and bloom. Of course, I could start out with larger plants...but still, crapes are not at the top of my list.


Forsythia, photo by phileole


4) Forsythia x intermedia 'Lynwood Gold': Yes, they're also sort of ubiquitous, but they do add a cheery yellow start to spring and supposedly provide a good early nectar source for bees. More importantly, they are reportedly very tough, rugged and drought-tolerant. Lynwood Gold supposedly can grow as fast as 2-4 feet per year and tops out around 8 feet tall and 10-feet wide. And it's available at a local nursery.


Magnolia grandiflora, Southern Magnolia, this is another popular dwarf cultivar called "Little Gem", photo by UGA College of Ag


5) Magnolia grandiflora, southern magnolia: The species can grow 60-80 feet tall, but there are a number of smaller cultivars. I'm leaning toward one called Teddy Bear (a.k.a. Southern Charm) that supposedly maxes out at 15-20 feet tall. Other advantages - it's evergreen, native, reportedly fairly drought tolerant and has beautiful fragrant white flowers (that are pollinated by beetles) and produces seeds for birds to eat. It's available at a local nursery. The only drawback I can see is that young Southern Magnolias sometimes look really sparse. So it might take the tree a few years to fill in...

Myrica cerifera, Wax Myrtle, photo by Sharpj99

6) Myrica cerifera, southern waxmyrtle: It's a native evergreen shrub that reportedly tolerates heat, drought, wind and full sun. It supposedly has a rapid growth rate and matures anywhere from 10-30 feet tall (so I might have to do some pruning to keep it at the desired height). The flowers reportedly attract butterflies and the berries (if both male and female plants are present) reportedly attract birds. In terms of drawbacks, we're at the northern end of its range, so I anticipate there could be some damage in tough winters, but southern waxmyrtle can reportedly bounce back quickly from winter damage during the warmer seasons.

Osmanthus americanus, Devilwood, photo by Katja Schulz


7) Osmanthus americanus, Devilwood, American Olive: A native evergreen shrub or small tree (reported height typically ranges from 10-20 feet tall, but can reach 50-feet in extraordinary circumstances), Devilwood is supposed to be fast-growing (1-3 feet per year), and tolerant of wind, drought, flooding and full sun.

Philadelphus lewisii, Lewis' Mock Orange, photo by Peter Stevens


8) Philadelphus lewisii, Lewis' Mock Orange: A native of the Western U.S., Lewis' Mock Orange height varies by cultivar, but the Natchez variety carried at a local nursery reportedly grows 6-8 feet tall and wide. It is reportedly wind-tolerant and drought-tolerant. The flowers are supposed to be fragrant. The shrub is deciduous and some sources recommend using rejuvenating pruning techniques (cutting the plant to the ground after flowering -- though I'm not sure if this is supposed to be an annual process), so I'm not sure whether it would make a good screen in that regard.

Ternstroemia gymnanthera, Cleyera, photo by Nemo's great uncle

9) Ternstroemia gymnanthera, Cleyera: An evergreen shrub that can grow 8-25 feet tall. I have a few concerns: (1) Reportedly prefers acidic soil whereas I think our soil is relatively neutral (although I could amend at planting and with some acidic fertilizer yearly thereafter, (2) contradictory information as to whether it requires partial shade or can handle full sun and (3) reportedly only has a moderate growth rate. To add one more layer of confusion and uncertainty, even though Ternstroemia gymnanthera's common name is "Cleyera" and even though Ternstroemia comes from Japan, this plant is apparently not the same as Cleyera japonica, which is also called Cleyera. Confused yet? Me too.

Burkwood Viburnum flowers, photo by Ralph Daily


10) Viburnums: There are many species and hybrids of Viburnum in the gardening trade. I'm interested in these four, all of which are supposed to be tough, wind-tolerant, heat-tolerant, sun-tolerant and drought-tolerant with a moderate to fast growth rate:


  • V. dentatum, Southern Arrowwood, I think this is closely related to V. bracteatum, native to much of Eastern United States, size varies depending on cultivar but there are several interesting ones in the 8-12 feet high range, deciduous but supposed to have good fall color, may sucker profusely

So that's the story. Any thoughts on the suitability of some/all of these plants for privacy screens in my sunny, windy, hot-then-cold, dry-then-wet backyard? Or have I overlooked the Best Plant Ever (if so, feel free to enlighten me) :)


PS - If you'd like to stay abreast of the latest developments at Garden of Aaron, you can now subscribe via email! Totally convenient, totally free - what could be nicer?

Thursday, July 4, 2013

Floral Fireworks for July 4th!


Happy 4th of July!

In honor of the occasion, I collected some patriotic photos from the garden.

Let's start with the RED...

Monarda didyma "Jacob Cline"
Monarda didyma "Jacob Cline"

...the WHITE...

Phlox paniculata "David"
Phlox paniculata "David"

Lobularia maritima, Sweet Alyssum

...and BLUE

Borago officinalis, Borage
Borago officinalis, Borage

There's a certain BUZZ of excitement in the air...

Echinacea purpurea, Purple Coneflower and Bumble Bee.
Echinacea purpurea, Purple Coneflower and Bumble Bee. (This bee actually slept on the flower overnight, which made it easy to make its photo on a cool and foggy summer morning before the sun had warmed it up enough to start flying around.)
Perovskia atriplicifolia, Russian Sage and Bumble Bee
Perovskia atriplicifolia, Russian Sage and Bumble Bee

...as everyone gets ready for some FIREWORKS!

Lonicera sempervirens, Coral Honeysuckle
Lonicera sempervirens, Coral Honeysuckle
Hemerocallis, Daylilies, unknown variety (Rosy Returns?)
Hemerocallis, Daylilies, unknown variety (Rosy Returns?)

Phlox paniculata, Garden Phlox, Eva Cullum
Phlox paniculata, Garden Phlox, Eva Cullum

Hibiscus moscheutos, Hardy Hibiscus, Lady Baltimore
Hibiscus moscheutos, Hardy Hibiscus, I believe this is "Lady Baltimore". Purchased via mail order last year, I thought she died in the heat and drought of 2012. She certainly didn't bloom last year. In fact, I contemplating shovel pruning the sad stem in winter. But sometimes procrastination is the best gardening choice. She leaped up cheerfully in springtime and this is already the second bloom of the year with budded promises of more to come. My other hardy hibiscus (Luna Swirl or Disco Belle? I can't remember which), purchased at a local garden center, bloomed last year and is Loaded with buds this year. Eager to see it flower!
Heliopsis helianthoides, Ox-Eye Sunflower, "Summer Sun"
Heliopsis helianthoides, Ox-Eye Sunflower, "Summer Sun". Purchased and planted this spring from Perennial Plant Society of Middle TN plant sale.


Helianthus annus, Sunflower. I received a bonus packet of sunflower seeds this spring (can't remember how) and I've been trying to figure out what variety they were. Then I remembered, they were mixed sunflower seeds. Which explains why this sunflower doesn't look anything like this next one...

Helianthus annus, Sunflower
Nearly six-feet tall and proudly puffy, these bright and beautiful sunflower blooms deliver an explosion of color. What a fireworks display! (And safe for all ages.) ;-)

Have a safe and happy holiday, y'all!

Monday, July 1, 2013

The Blooms Continue - Gaillardia, Sunflower, Liatris spicata, Phlox paniculata, Persian Carpet Zinnias, Hardy Blue Plumbago, Rose of Sharon and more!

As July begins, everything is still coming up Roses (of Sharon) here in the Garden of Aaron!


Here are some highlights:

Hibiscus syriacus, Rose of Sharon, "Blue Bird"
Hibiscus syriacus, Rose of Sharon, "Blue Bird" from Gardens in the Wood. Many hibiscus are reportedly weedy/invasive, but Blue Bird is supposed to be sterile and therefore not likely to become a problem. CORRECTION - Dottie @ Gardens in the Wood of Grassy Creek correctly points out in the comments section below that Blue Bird is not a sterile Hibiscus syriacus. And in fact she also notes that even the "sterile" Rose of Sharons may reseed a little. Apologies for my mistake.

Hibiscus syriacus, Rose of Sharon, Blue Bird
Despite its tropical appearance, Hibiscus syriacus is actually hardy to zone 5! I like the way that Blue Bird's buds are dark blue, but the flower itself is light blue when it opens. Even though it was 90+ degrees today in Tennessee, Blue Bird still looked cool as a cucumber.

Vitex agnus-castus, Chaste Tree, Monk's Pepper with Bees
Vitex agnus-castus, Chaste Tree, Monk's Pepper. The bees are enthusiastic about these blue flowers.

Vitex agnus-castus, Chaste Tree, Monk's Pepper
Here's a step back to see the big picture with regard to the Vitex. Just planted last autumn, this is the Vitex's first year in the garden. Right now it is a shrub, but supposedly it can grow up to 15-20 feet tall.

Gaillardia pulchella, Firewheel, Blanket Flower, Indian Blanket
Gaillardia pulchella, Firewheel, Blanket Flower, Indian Blanket, purchased this plant at the Perennial Plant Society of Middle TN plant sale. It is a cultivar called "Arizona Apricot". Plunked it down next in a hot windblown area next to the baking concrete driveway. Hey, I'm trying to make it feel at home like it's in Arizona! ;-)

Liatris spicata, Blazing Star, Gayfeather
Liatris spicata, Blazing Star, Gayfeather. This is a native prairie plant that attracts bumble bees. Can you see one on the side of the right flower stalk?


Here's a step back to show what Liatris spicata looks like from a distance. The flowers start opening at the top of the stalk and then work their way down. This is my third year trying to grow Liatris spicata. The first year, it disappeared shortly after I planted it. I assumed it had died! But it popped back above ground last year, only to wither and bake away in the record heat and drought. This year is finally the year it could show its true self and put on a show! Once established, I think Liatris spicata is supposed to be pretty tough, so hopefully it will continue to get bigger and better in future years. 

Phlox paniculata, Garden Phlox, "David"
Phlox paniculata, Garden Phlox, "David". So far it gets bigger and better each year! 



Phlox paniculata is partially self-cleaning. Some of the dead flowers stay on the plant, but others fall off and create this nice shower of white petals on the ground nearby. I find it poetic. It reminds me of the petals that carpet the ground when cherry blossoms fall.

Echinacea purpurea, Eastern Purple Coneflower with Bee
Echinacea purpurea, Eastern Purple Coneflower. Another native to Tennessee. Another plant that buzzes with bees all day long. 

Echinacea purpurea, Eastern Purple Coneflower with Bumble Bee
Couldn't resist taking one more shot of another purple coneflower and another busy buzzy bee.

Perovskia atriplicifolia, Russian Sage. All three Russian Sage are looking much better this year compared to last year. There are still a few yellow leaves at the bottom of the plants, but overall they look healthier and stronger. The Russian Sage attracts some bees, but I have not seen nearly as many bees on the plants this year now that they have to compete for attention with the coneflowers, the Vitex and the Liatris.


Ceratostigma plumbaginoides, Hardy Blue Plumbago has begun to flower! Stay tuned for an upcoming blog post with a detailed look at the pros and cons of this tough groundcover.


Monarda didyma, Scarlet Beebalm, Oswego Tea, "Jacob Cline"
Monarda didyma, Scarlet Beebalm, Oswego Tea, "Jacob Cline". Based on the shape and color of the flowers, you would think that Jacob Cline would attract the hummers. I've seen a hummingbird investigate the plant on its way to or from the nearby Coral Honeysuckle, but I have not yet seen the bird take a sip from the Monarda.


Monarda didyma, Scarlet Beebalm, Oswego Tea, "Jacob Cline".
Here's a broader look at Jacob Cline monarda. I will say that the flowers - which are listed as edible by various sources - taste better than the leaves, IMHO.

Zinnia haageana "Persian Carpet". This is very different from the more popular Z. elegans that I featured in last week's garden photos. Z. haageana has narrower leaves, smaller flowers and a reputation for being even tougher, more drought-tolerant, more heat-tolerant and more mildew-resistant than its big elegant cousin. I will say that the flowers - and the whole plant so far - are smaller than I had anticipated. But Z. haageana has a reputation for continuing to grow and flower until frost (without any deadheading), so these plants still have plenty of time to make a big impact. In the meantime, I like the cheerful golden colors.

Zinnia haageana "Persian Carpet" with Bee
The Z. haageana flowers seem simpler than many of the Z. elegans blooms - it's my understanding that simpler is better from a bee's standpoint since the bee is looking for quick access to pollen and/or nectar without having to dig through a fluffy mass of petals.This bee seemed happy to have found its own personal "Persian Carpet".

Do tomato flowers count? This is Lycopersicon lycopersicum "Blondkopfchen", purchased at a local farmers market. It's supposed to be a heavy producer of golden cherry tomato fruit.

Bolted lettuce
It's hard to tell from this perspective, but this is a 3-foot tall lettuce plant that has gone to seed. Every day there are a few yellow flowers and a few seedheads. I find it interesting that the plant does not flower all at once, but spaces its flowering and seed dispersal over several weeks. The seeds are feathered - like dandelion seeds - to aid in wind dispersal, I presume.


White Cosmos bipinnatus and Bee
There are plenty of Cosmos bipinnatus in bloom and therefore plenty of happy bees.

More blooms now on the Agastache "Golden Jubilee". Despite a reputation for attracting pollinators, I have not seen many bees or wasps or hoverflies on this plant. Perhaps it attracts really tiny ones that escape my notice? Do you grow Agastache and does it attract any pollinators in your garden?


Platycodon grandiflorus, Balloon Flower "Mariesii" flower bud
Platycodon grandiflorus, Balloon Flower "Mariesii". Not *quite* flowering yet, but the balloon-shaped bud is attractive and interesting on its own. This one stalk is at least two-feet tall even though the rest of the plant is much shorter. It's also interesting how different Platycodon flower at different times. The blue Platycodon that I added in the full sun back garden seems nearly finished, but this one is just starting and the white Platycodon nearby ("Astra White") has been blooming for weeks and is not done yet.

Salvia nemorosa "Blue Hill". Whereas many of my other flowering plants seem to draw mostly big bees (bumble bees and perhaps carpenter bees, I presume), the Salvia attracts all sorts of bees, including what I think may be a honey bee in this photo. That said, it's been sort of a frustrating experience growing two types of Salvia nemorosa this year. I planted both Blue Hill and May Night last autumn. They survived the winter with a tattered yet evergreen rosette of leaves and then put on a lot of growth in the spring and quickly sent up flower spikes. But the flower spikes emerged into an unusually cold and rainy spring, thus hardly attracting any bees. By the time the bees did show up, the flower spikes were nearly finished! I've tried deadheading the flower spikes (which I found tedious) which seemed to provoke a sparse rebloom. Maybe it will rebloom more in autumn? And maybe I would have had an easier time if I had used something like a hedge trimmer to trim back the sage? I tried a cheap bypass pruner that tended to bend the tough stems rather than slicing them. Frustrating.

Borago officinalis, Borage flower and fuzzy buds
Is Borage (Borago officinalis) the fuzziest plant ever? Adorable (and reportedly edible in small quantities if you can get past all that fuzz). I planted it not primarily for the pretty blue flowers, the fuzzy buds or the calming blue-grey felted leaves, but for its reputed ability to attract bees to the garden. I haven't seen proof of that claim yet, but then this is the first Borage flower to open. Patience, patience... Borage is one of those plants that is supposed to self-sow vigorously. I sowed some of the borage near my tomato plants since borage has a reputation for repelling hornworms and other tomato pests.

Sunflower stalk chomped by a deer
Nothing to see here, folks. This would have been a Sunflower (Helianthus annus) bloom someday, were it not for an injurious nighttime encounter with what I suspect was a deer (or a Really Tall Rabbit). Several other sunflower stalks and a bolted lettuce also got the chomp.

Tall sunflower, Helianthus annus
But the deer left some sunflowers for us to enjoy! This is the tallest sunflower in my garden - over 5-feet tall., standing straight and proud in the sun. The first flower is just about to unfurl its cheerful petals.

Finally, one more Sunflower (Helianthus annus), this one next to the Gaillardia in that windy, baking spot between a concrete driveway and concrete walkway at the corner of the house. Does the sunflower mind these harsh conditions? Not one whit. The sunflower abides (like The Dude).